Forum: Unleashed

DAY1SVR: Day 1 Convective Outlook

From COD Weather Processor @1:2320/107 to All on Mon Aug 3 12:28:10 2026

ACUS01 KWNS 031227
SWODY1
SPC AC 031226

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0726 AM CDT Mon Aug 03 2026

Valid 031300Z - 041200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
UPPER MIDWEST AND SOUTHEAST ARIZONA...

...SUMMARY...
Scattered severe thunderstorms are possible today across parts of
northern Minnesota into adjacent portions of the eastern Dakotas, as
well as across southeastern Arizona.

...Upper Midwest southward into the central High Plains...
Radar mosaic shows a loose cluster of mainly occasionally strong
thunderstorm activity over the Red River Valley. This activity has
developed partly in response to isentropic lift downstream of an eastward-migrating mid-level speed max over the northern Rockies and
adjacent plains. The morning showers/thunderstorms will likely
reinforce a frontal zone draped southwest to northeast over the
region.

Heating in wake of early day cloud cover will foster moderate
destabilization by mid afternoon as mid to upper-level flow
gradually strengthens. The initial storms later today will likely
pose a risk for severe gusts and large hail and perhaps a tornado if
a couple of storms can acquire supercell characteristics and mature
within a moist axis ahead of the front. Otherwise, small clusters
will probably evolve with time and pose mainly a wind/hail threat.
Farther south, lower storm coverage is expected along a surface
trough into the central High Plains. Isolated, high-based storms
will slowly move east within a hot airmass featuring very steep
lapse rates. Isolated severe gusts may accompany the stronger cores
and outflow before these storms wane by mid evening.

...Southeastern Arizona/adjacent New Mexico...
Model guidance continues to indicate a belt of enhanced mid to upper northeasterlies over northern Sonora into far southeastern
AZ/southwestern NM. Very strong heating resulting in moderate
destabilization and orographic lift will favor scattered
thunderstorm development by late afternoon into the early evening.
Models (e.g., MPAS, HREF) show a cluster or two propagating on
outflow into the lower deserts during the evening with very steep
0-3 km lapse rates preceding this convection. Severe gusts 60 to 75
mph will be the primary hazard.

...Northern Mid Atlantic through western New England...
Along and ahead of a weak cold front, trailing a deepening surface
low migrating northeastward toward the lower St. Lawrence Valley, boundary-layer destabilization will probably be slowed, if not
inhibited, by weak mid-level lapse rates and early day cloud cover/precipitation. However, strengthening deep-layer wind fields
and shear will potentially become more supportive of organized
thunderstorm development. If a couple of stronger updrafts can
develop, a risk for damaging wind gusts and perhaps a brief tornado
may materialize---contingent on sufficient destabilization occurring
prior.

..Smith/Bentley.. 08/03/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Aug 3 16:40:26 2026

ACUS01 KWNS 031632
SWODY1
SPC AC 031630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Mon Aug 03 2026

Valid 031630Z - 041200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN PLAINS INTO THE UPPER MIDWEST...AND SOUTHERN ARIZONA...

...SUMMARY...
Scattered severe thunderstorms are possible today into tonight
across parts of the eastern Dakotas into northern Minnesota, as well
as across portions of southern Arizona.

...Northern/Central Plains into the Upper Midwest...
Post-frontal thunderstorms occurring this morning across ND have
remained mostly sub-severe over the past couple of hours. A stout
low-level inversion noted on the observed 12Z INL sounding will
likely inhibit surface-based thunderstorms from developing until
late this afternoon or early evening across the eastern Dakotas into
northern MN. Still, gradual airmass destabilization is anticipated
across this region along/ahead of a cold front through the
afternoon. Large-scale ascent attendant to an ejecting mid-level
shortwave trough from MT into ND will eventually aid scattered
convective development along/near the front, most likely by 22-01Z.
Moderate instability coupled with strong deep-layer shear will
support some threat for supercells and large hail initially, before
upscale growth into clusters supports an increasing severe/damaging
wind threat with eastward extent into northern MN this evening. A
tornado or two may also occur as low-level shear gradually increases
in a narrow corridor ahead of the front this evening.

Isolated to widely scattered thunderstorm development is forecast
with southward extent into the central High Plains. A hot and very
well-mixed low-level airmass ahead of the front/surface trough
across this area may support occasional severe gusts with convective
outflow. But, weaker mid-level winds and related modest deep-layer
shear should result in only loosely organized clusters/cells. This
activity should weaken with the loss of daytime heating.

...Southwest...
Around 15-25 kt of east-northeasterly mid-level winds will persist
today across far southern AZ/NM, to the south of prominent upper
ridging that will remain anchored over the Southwest. Recent visible
satellite imagery shows mostly clear conditions across southeast AZ,
with latest surface observations showing ample low-level moisture
present (surface dewpoints generally in the low to mid 60s across
lower elevations). Ample heating of this moist airmass will support
moderate instability by mid afternoon. Current expectations are for thunderstorms to initially develop over the higher terrain of
southeast AZ as convective temperatures are reached, and
subsequently spread west-southwestward into the lower deserts
through the evening. Some organization/clustering appears possible
with this activity, and the Slight Risk for severe wind gusts up to
60-75 mph has been maintained with no changes. Isolated hail may
also occur with the strongest cores that develop initially.

...Northeast/Northern Mid-Atlantic...
An upper trough with enhanced mid-level south-southwesterly flow
will advance eastward across the Northeast and northern Mid-Atlantic
today. A weak surface low should develop northward into southern
Quebec, with a trailing cold front advancing eastward across the
Northeast this afternoon/evening. Filtered daytime heating of a
seasonably very moist airmass (reference 12Z observed soundings from OKX/ALB/GYX) will support modest MLCAPE up to 500 J/kg, even though
mid-level lapse rates remain quite poor. Thunderstorms developing
along and ahead of the cold front may pose an isolated threat for
damaging winds given the enhanced flow present at low/mid levels. A
brief tornado or two could also occur across parts of New England
where effective SRH may be locally greater in tandem with a
southerly low-level jet. Still, the overall poor thermodynamic
environment should limit a greater severe wind threat from
developing this afternoon.

..Gleason/Lyons.. 08/03/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Aug 3 20:01:44 2026

ACUS01 KWNS 032001
SWODY1
SPC AC 031959

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0259 PM CDT Mon Aug 03 2026

Valid 032000Z - 041200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN PLAINS INTO THE UPPER MIDWEST...AND SOUTHERN ARIZONA...

...SUMMARY...
Scattered severe thunderstorms are possible today into tonight
across parts of the eastern Dakotas into northern Minnesota, as well
as across portions of southern Arizona.

...20Z Update...
The MRGL Risk in the Northeast was trimmed behind an eastward-moving
band of frontal convection. This activity will continue to pose a
risk of damaging wind gusts and possibly a brief tornado this
afternoon, before moving into an increasingly stable air mass
sampled by the CAR 18Z sounding and/or moving off the southern New
England Coast.

Farther west, the latest surface analysis depicts a surface low at
the intersection of a cold front and lee trough in far northeast CO.
Current thinking is that high-based thunderstorms will develop in
the vicinity of this feature and spread east/northeastward into a
deeply mixed boundary layer in southwestern NE this evening -- where
a robust warm layer is present at the base of the EML (per LBF 18Z
sounding). There is some potential that this environment supports a
localized corridor of enhanced severe wind gusts (some upwards of 75
mph). However, the aforementioned capping and spatially limited
corridor casts uncertainty on the overall risk -- precluding an
upgrade at this time.

Elsewhere, the forecast remains on track and no changes were made
with this update.

..Weinman.. 08/03/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Mon Aug 03 2026/

...Northern/Central Plains into the Upper Midwest...
Post-frontal thunderstorms occurring this morning across ND have
remained mostly sub-severe over the past couple of hours. A stout
low-level inversion noted on the observed 12Z INL sounding will
likely inhibit surface-based thunderstorms from developing until
late this afternoon or early evening across the eastern Dakotas into
northern MN. Still, gradual airmass destabilization is anticipated
across this region along/ahead of a cold front through the
afternoon. Large-scale ascent attendant to an ejecting mid-level
shortwave trough from MT into ND will eventually aid scattered
convective development along/near the front, most likely by 22-01Z.
Moderate instability coupled with strong deep-layer shear will
support some threat for supercells and large hail initially, before
upscale growth into clusters supports an increasing severe/damaging
wind threat with eastward extent into northern MN this evening. A
tornado or two may also occur as low-level shear gradually increases
in a narrow corridor ahead of the front this evening.

Isolated to widely scattered thunderstorm development is forecast
with southward extent into the central High Plains. A hot and very
well-mixed low-level airmass ahead of the front/surface trough
across this area may support occasional severe gusts with convective
outflow. But, weaker mid-level winds and related modest deep-layer
shear should result in only loosely organized clusters/cells. This
activity should weaken with the loss of daytime heating.

...Southwest...
Around 15-25 kt of east-northeasterly mid-level winds will persist
today across far southern AZ/NM, to the south of prominent upper
ridging that will remain anchored over the Southwest. Recent visible
satellite imagery shows mostly clear conditions across southeast AZ,
with latest surface observations showing ample low-level moisture
present (surface dewpoints generally in the low to mid 60s across
lower elevations). Ample heating of this moist airmass will support
moderate instability by mid afternoon. Current expectations are for thunderstorms to initially develop over the higher terrain of
southeast AZ as convective temperatures are reached, and
subsequently spread west-southwestward into the lower deserts
through the evening. Some organization/clustering appears possible
with this activity, and the Slight Risk for severe wind gusts up to
60-75 mph has been maintained with no changes. Isolated hail may
also occur with the strongest cores that develop initially.

...Northeast/Northern Mid-Atlantic...
An upper trough with enhanced mid-level south-southwesterly flow
will advance eastward across the Northeast and northern Mid-Atlantic
today. A weak surface low should develop northward into southern
Quebec, with a trailing cold front advancing eastward across the
Northeast this afternoon/evening. Filtered daytime heating of a
seasonably very moist airmass (reference 12Z observed soundings from OKX/ALB/GYX) will support modest MLCAPE up to 500 J/kg, even though
mid-level lapse rates remain quite poor. Thunderstorms developing
along and ahead of the cold front may pose an isolated threat for
damaging winds given the enhanced flow present at low/mid levels. A
brief tornado or two could also occur across parts of New England
where effective SRH may be locally greater in tandem with a
southerly low-level jet. Still, the overall poor thermodynamic
environment should limit a greater severe wind threat from
developing this afternoon.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Aug 4 01:01:16 2026

ACUS01 KWNS 040101
SWODY1
SPC AC 040059

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Mon Aug 03 2026

Valid 040100Z - 041200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WESTERN AND NORTHERN MINNESOTA...

...SUMMARY...
Thunderstorms with severe wind gusts and isolated large hail will be
possible this evening over parts of western and northern Minnesota.
Severe wind gusts are also expected in parts of southeastern
Arizona.

...Western and Northern Minnesota...
On water vapor imagery, west-southwesterly mid-level flow is present
over much of the north-central U.S., with a subtle shortwave trough
evident over northern Minnesota. At the surface, a cold front is
located over northwestern Minnesota. Surface dewpoints ahead of the
front range from 65 to 70 F, and the RAP has MLCAPE in the 1500 to
2500 J/kg range. This is supporting scattered thunderstorm
development across northwest Minnesota. In addition, a 60 to 70 knot
mid-level jet is moving over the top of this moist and unstable
airmass, and is creating moderate deep-layer shear. This will be
favorable for organized storms capable of producing severe wind
gusts and isolated large hail. The severe threat will be maximized
with supercells that develop.

...Central High Plains...
The latest surface analysis shows a cold front located from
northeast Colorado northeastward into central Nebraska, along which
low-level convergence is maximized. This is supporting scattered
thunderstorm development. Just ahead of the front, an axis of
moderate instability is analyzed by the RAP over central and
southwest Nebraska, where MLCAPE is estimated to be from 1000 to
2000 J/kg. In addition, low to mid-level lapse rates are steep
according to the RAP, with 0-3 km lapse rates exceeding 8 C/km over
parts of southwest Nebraska. This environment will contribute to
strong downdrafts capable of producing isolated severe gusts.

...Southeast Arizona...
A moderately unstable airmass is currently located across southeast
Arizona, where the RAP has MLCAPE in the 1000 to 2000 J/kg range.
Thunderstorms are ongoing along the northern edge of the stronger
instability. These storms will move west-southwestward across the
remainder of southeastern Arizona over the next few hours. Steep low
to mid-level lapse rates will contribute to a potential for severe
wind gusts.

..Broyles.. 08/04/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Aug 4 05:49:44 2026

ACUS01 KWNS 040549
SWODY1
SPC AC 040547

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1247 AM CDT Tue Aug 04 2026

Valid 041200Z - 051200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN ROCKIES...SOUTHEAST ARIZONA AND IN THE WESTERN
CAROLINAS...

...SUMMARY...
Thunderstorms with severe wind gusts and hail will be possible from
late afternoon into mid evening in parts of southern Rockies and
southeast Arizona. Severe gusts will also be possible in parts of
the western Carolinas.

...Southern Rockies...
A pocket of moderate instability will develop today across the
southern Rockies. As surface temperatures warm, convection will
initiate in the higher terrain of the Sangre de Cristos by
afternoon. Thunderstorms will develop and move east-southeastward
into the lower elevations of northeast New Mexico and southeast
Colorado. The instability combined with steep low to mid-level lapse
rates will support isolated severe wind gusts and hail.

...Southeast Arizona...
An axis of moderate instability will develop this afternoon in
southeast Arizona. MLCAPE is forecast to peak in the 1000 to 1500
J/kg range by late afternoon with thunderstorms developing near the
instability axis. The storms will move west-southwestward across
southeast Arizona from late afternoon into the early to mid evening.
The instability along with steep low to mid-level lapse rates will
support isolated severe wind gusts.

...Western Carolinas...
A mid-level low will remain over northern Georgia today. To the east
of the low, an axis of moderate instability is forecast to develop
over the western Carolinas by afternoon. Warming surface
temperatures in the higher terrain will result in scattered
convective initiation across the southern Appalachians. As
instability peaks and low-level lapse rates become steep in the
afternoon, an isolated wind-damage threat is expected to develop in
the western Carolinas.

..Broyles/Supinie.. 08/04/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Aug 4 12:38:06 2026

ACUS01 KWNS 041237
SWODY1
SPC AC 041235

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0735 AM CDT Tue Aug 04 2026

Valid 041300Z - 051200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR SOUTHEAST
ARIZONA...

...SUMMARY...
Scattered severe wind gusts are possible across southeast Arizona
during the late afternoon and evening.

...Southeast Arizona...
A flattened mid to upper-level ridge over the Desert Southwest will
feature a moderate belt of easterlies across Sonora into far
southern portions of NM and AZ. A seasonably moist airmass will
undergo strong heating and result in moderate buoyancy by mid
afternoon (1000-2000 J/kg MLCAPE) per RAP/NAM forecast soundings.
Initially widely scattered storm development over the higher terrain
will gradually move west across southeast AZ during the late
afternoon and evening. Steep 700-500 mb lapse rates (around 8 deg
C/km) atop very steep low-level lapse rates ahead of this activity
will support ample evaporative cooling potential with the stronger
thunderstorm cores. The resultant microbursts and associated
outflow will yield a risk for 60-80 mph gusts as storms congeal into
a small cluster or two.

...Sangre de Cristos and adjacent plains...
A local maximum in buoyancy is depicted by model guidance near the
Raton Mesa by mid-late afternoon where widely scattered storms will
likely develop. Some of the CAMs show this activity moving
southeast into parts of the OK-TX Panhandles during the early
evening with an isolated risk for severe gusts. Marginally severe
hail is possible with the stronger cores.

...Western Carolinas...
A mid-level low will remain over northern Georgia today. To the
east of the low, an axis of moderate instability is forecast to
develop over the western Carolinas by afternoon. Warming surface
temperatures in the higher terrain will result in scattered
convective initiation across the southern Appalachians. As
instability peaks and low-level lapse rates become steep in the
afternoon, an isolated wind-damage threat is expected to develop in
the western Carolinas.

..Smith/Bentley.. 08/04/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Aug 4 16:29:12 2026

ACUS01 KWNS 041627
SWODY1
SPC AC 041625

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1125 AM CDT Tue Aug 04 2026

Valid 041630Z - 051200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHEAST ARIZONA...

...SUMMARY...
Scattered severe wind gusts are possible across southeast Arizona
during the late afternoon and evening.

...Southeast Arizona...
A flattened mid/upper-level ridge over the Southwest will continue
to feature a belt of modestly enhanced mid-level easterlies across
northern Mexico into far southern portions of AZ/NM. Even with
convective overturning yesterday, a seasonably moist low-level
airmass across southeast AZ/southwest NM will undergo strong heating
this afternoon, with up to 1000-2000 J/kg MLCAPE forecast per latest
RAP/NAM forecast soundings. Initial widely scattered convective
development over the higher terrain will gradually move westward
across southeast AZ during the late afternoon and evening. A very
well-mixed boundary layer with steep low/mid-level lapse rates ahead
of this activity will support ample evaporative cooling potential
with the stronger thunderstorm downdrafts. The resultant microbursts
and associated outflow should yield a risk for 60-80 mph gusts as
thunderstorms potentially congeal into one or more small clusters
through the evening.

...Eastern Nebraska into Iowa and Northern Missouri...
Elevated thunderstorms are ongoing late this morning across parts of
NE to the north of a surface cold front extending from the southern
High Plains northeastward to the Upper Midwest. Stronger mid-level
flow and related large-scale ascent will tend to remain displaced to
the north of the front through the period. But, there may still be
some potential for a surface-based thunderstorm or two to develop
along/near the front late this afternoon/early evening across
IA/northern MO and vicinity in a moderately unstable airmass. While
still appearing fairly conditional, isolated hail/damaging winds may
occur if convection develops. Otherwise, a greater chance for
additional elevated thunderstorms should exist tonight into early
Wednesday morning from eastern NE into IA. This activity may also
pose an isolated hail/gusty wind threat.

...Raton Mesa into the Southern/Central High Plains...
Although overall magnitudes will remain limited, a local maximum in
instability should develop this afternoon near the Raton Mesa into
southeast CO, where widely scattered thunderstorms will likely
develop in a post-frontal low-level upslope regime. Recent
high-resolution guidance continues to show this activity moving
slowly southeastward into parts of the OK/TX Panhandles during the
early evening. While deep-layer shear is expected to remain modest
(20-30 kt), marginally severe hail is possible with the stronger
cores, and isolated severe gusts may occur with any loosely
organized clusters that can develop.

...Southern Appalachians/Western Carolinas...
A closed mid-level low will remain centered over GA today. To the east/northeast of this low, filtered daytime heating of a moist
low-level airmass will support the development of moderate
instability over the western Carolinas into north GA and eastern TN
this afternoon. Scattered thunderstorms will continue to develop
across this region through 17-19Z as convective temperatures are
reached. Even though deep-layer shear will remain weak, an isolated
threat for damaging winds associated with microbursts may develop as
low-level lapse rates gradually steepen.

..Gleason/Lyons.. 08/04/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Aug 4 19:50:46 2026

ACUS01 KWNS 041950
SWODY1
SPC AC 041948

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0248 PM CDT Tue Aug 04 2026

Valid 042000Z - 051200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHEAST ARIZONA...

...SUMMARY...
Scattered severe wind gusts are possible across southeast Arizona
during the late afternoon and evening.

...20Z Update...
No major changes have been made to the outlook. Initial high-terrain
storm development is expected to move west-southwestward across
southeast AZ from late afternoon into the evening, with a primary
threat of scattered severe gusts. Other strong to locally severe
storms are possible through the afternoon into the early evening
across parts of the Raton Mesa and south-central High Plains, parts
of IA/northern MO, and the southern Appalachians/western Carolinas
region. Late tonight, a few strong elevated storms may develop
across parts of southeast NE, IA, and northern MO. See the previous
discussion below for more information.

..Dean.. 08/04/2026

.PREV DISCUSSION... /ISSUED 1125 AM CDT Tue Aug 04 2026/

...Southeast Arizona...
A flattened mid/upper-level ridge over the Southwest will continue
to feature a belt of modestly enhanced mid-level easterlies across
northern Mexico into far southern portions of AZ/NM. Even with
convective overturning yesterday, a seasonably moist low-level
airmass across southeast AZ/southwest NM will undergo strong heating
this afternoon, with up to 1000-2000 J/kg MLCAPE forecast per latest
RAP/NAM forecast soundings. Initial widely scattered convective
development over the higher terrain will gradually move westward
across southeast AZ during the late afternoon and evening. A very
well-mixed boundary layer with steep low/mid-level lapse rates ahead
of this activity will support ample evaporative cooling potential
with the stronger thunderstorm downdrafts. The resultant microbursts
and associated outflow should yield a risk for 60-80 mph gusts as
thunderstorms potentially congeal into one or more small clusters
through the evening.

...Eastern Nebraska into Iowa and Northern Missouri...
Elevated thunderstorms are ongoing late this morning across parts of
NE to the north of a surface cold front extending from the southern
High Plains northeastward to the Upper Midwest. Stronger mid-level
flow and related large-scale ascent will tend to remain displaced to
the north of the front through the period. But, there may still be
some potential for a surface-based thunderstorm or two to develop
along/near the front late this afternoon/early evening across
IA/northern MO and vicinity in a moderately unstable airmass. While
still appearing fairly conditional, isolated hail/damaging winds may
occur if convection develops. Otherwise, a greater chance for
additional elevated thunderstorms should exist tonight into early
Wednesday morning from eastern NE into IA. This activity may also
pose an isolated hail/gusty wind threat.

...Raton Mesa into the Southern/Central High Plains...
Although overall magnitudes will remain limited, a local maximum in
instability should develop this afternoon near the Raton Mesa into
southeast CO, where widely scattered thunderstorms will likely
develop in a post-frontal low-level upslope regime. Recent
high-resolution guidance continues to show this activity moving
slowly southeastward into parts of the OK/TX Panhandles during the
early evening. While deep-layer shear is expected to remain modest
(20-30 kt), marginally severe hail is possible with the stronger
cores, and isolated severe gusts may occur with any loosely
organized clusters that can develop.

...Southern Appalachians/Western Carolinas...
A closed mid-level low will remain centered over GA today. To the east/northeast of this low, filtered daytime heating of a moist
low-level airmass will support the development of moderate
instability over the western Carolinas into north GA and eastern TN
this afternoon. Scattered thunderstorms will continue to develop
across this region through 17-19Z as convective temperatures are
reached. Even though deep-layer shear will remain weak, an isolated
threat for damaging winds associated with microbursts may develop as
low-level lapse rates gradually steepen.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Aug 5 00:42:22 2026

ACUS01 KWNS 050042
SWODY1
SPC AC 050040

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0740 PM CDT Tue Aug 04 2026

Valid 050100Z - 051200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHERN ARIZONA...

...SUMMARY...
Thunderstorms with severe wind gusts and hail will be possible this
evening in parts of southern Arizona, the southern Rockies, the
southern High Plains and the Upper Midwest.

...Southern Arizona...
The latest surface analysis shows a sufficiently moist airmass over
southern Arizona, where surface dewpoints are in the upper 50s to
around 60 F. This is contributing to moderate instability over parts
of southern Arizona, with the RAP suggesting that MLCAPE is in the
1000 to 2000 J/kg range. Thunderstorms have developed in the higher
terrain of southwest New Mexico. These storms will move
west-southwestward across southern Arizona this evening. In addition
to the instability, surface temperature-dewpoint spreads across this
airmass are large which is resulting in very steep low-level lapse
rates. This will contribute to a potential for severe wind gusts
this evening.

...Southern Rockies/Southern High Plains...
Scattered thunderstorms are ongoing in the southern Rockies early
this evening. These storms will move east-southeastward across
southeastern Colorado and northeastern New Mexico this evening,
where the RAP has SBCAPE around 1000 J/kg with moderate deep-layer
shear and steep low to mid-level lapse rates. The environment will
support an isolated potential for severe wind gusts and hail over
the next few hours.

...Upper Midwest...
An upper-level trough will move through the north-central U.S. this
evening. Ahead of the trough, a moist and unstable airmass will be
in place over the mid Missouri and mid to upper Mississippi Valleys.
An axis of low-level moisture is analyzed from northeast Kansas into
southeast Iowa, where surface dewpoints are in the 70s F. This is
contributing to moderate instability with the RAP showing MLCAPE in
the 2000 to 3500 J/kg range. Short-term model forecasts suggest that
scattered thunderstorms will develop near the instability axis
during the overnight period. The instability along with about 30
knots of 0-6 km shear will support an isolated wind-damage threat.

..Broyles.. 08/05/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Aug 5 05:33:48 2026

ACUS01 KWNS 050533
SWODY1
SPC AC 050531

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1231 AM CDT Wed Aug 05 2026

Valid 051200Z - 061200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID MISSISSIPPI VALLEY...SOUTHERN HIGH PLAINS...AND SOUTHEASTERN
ARIZONA...

...SUMMARY...
Thunderstorms with isolated severe wind gusts and hail will be
possible from this afternoon into the overnight across parts of the
mid Mississippi Valley. Isolated severe gusts may also occur in
parts of the southern High Plains, and in southeastern Arizona.

...Mid Mississippi Valley...
An upper-level trough will move eastward today across the
north-central U.S. At the surface, a quasi-stationary front will be
located from the central Plains northeastward into the mid
Mississippi Valley. Along and to the south of the front, surface
dewpoints will be in the lower to mid 70s F. As surface temperatures
warm today, moderate instability will develop to the south of the
front. Large-scale ascent associated with the trough will support
scattered to numerous thunderstorm development from this afternoon
into tonight across much of Missouri and Illinois.

RAP forecast soundings late this afternoon near the instability axis
in northeast Missouri have MLCAPE near 2000 j/kg, with 0-6 km shear
around 35 knots. This may support supercell development with storms
that remain discrete. However, high-resolution models suggest that
storm mode could be more favorable for multicells due to widespread
convective coverage. Although low-level lapse rates will be poor,
the instability and moderate deep-layer shear could be enough for
isolated severe wind gusts and hail.

...Southern High Plains...
West-northwesterly mid-level flow will be in place today across much
of the central U.S. A small pocket of moderate instability is
forecast to develop over southeast Colorado this afternoon. This
will aid convective initiation in the foothills of the southern
Rockies. During the late afternoon and early evening, storms are
expected to move east-southeastward into the lower elevations of the northwestern Texas Panhandle and western Oklahoma Panhandle. The
instability and steep low to mid-level lapse rates may support an
isolated threat for severe wind gusts.

...Southeastern Arizona...
A sufficiently moist airmass will be in place today across southern
Arizona. As surface temperatures warm, moderate instability will
develop over much of southeast Arizona by afternoon. Convection is
expected to form in the higher terrain of southwest New Mexico, with
storms moving west-southwestward across southeast Arizona from late
afternoon into the early evening. Very steep low-level lapse rates
and large temperature-dewpoint spreads will contribute to a
potential for isolated severe wind gusts.

..Broyles/Supinie.. 08/05/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Aug 5 12:47:18 2026

ACUS01 KWNS 051247
SWODY1
SPC AC 051245

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 AM CDT Wed Aug 05 2026

Valid 051300Z - 061200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID MISSISSIPPI VALLEY...SOUTHERN HIGH PLAINS...AND SOUTHEASTERN
ARIZONA...

...SUMMARY...
Isolated severe thunderstorms are possible today across the mid
Mississippi Valley. Isolated severe gusts may also occur in parts
of the southern High Plains, and in southeastern Arizona.

...Mid Mississippi Valley...
Water-vapor imagery this morning shows a broad upper trough over the north-central U.S. with a couple of embedded disturbances. A
leading weak impulse appears associated with a small cluster of
strong to locally severe activity early this morning across the
IA-MO border vicinity, near and immediately north of a stationary
front. These showers/thunderstorms will likely continue east of the
MS River but it remains unclear whether these storms maintain a
localized risk for severe before gradually weakening. Later today,
ascent associated with an upstream disturbance moving through the
base of the larger-scale trough over NE into IA, will favor
additional storm development as the boundary layer heats south of
the frontal zone. Moderate buoyancy is forecast by guidance and
sufficient deep-layer shear will support some potential storm
organization. The stronger storms may yield an episodic severe risk
before gradually diminishing during the evening.

...Southeastern Arizona...
A seasonably moist airmass sampled this morning by surface
observations (lower 60s F dewpoints) will undergo strong heating
through late afternoon. Orographic lifting will favor convection
developing over the higher terrain and gradually
spreading/developing into the lower deserts during the early
evening. Very steep low to mid-level lapse rates will contribute
towards a risk for strong downdrafts capable of a microburst threat
(60-80 mph). Considered a Slight-Risk based on potentially
scattered storm coverage moving into the lower deserts, but
sufficient model run-to-run (time-lagged HRRR) variability and model
ensemble spread (i.e., 00z HREF vs. REFS) preclude a wind-driven
upgrade at this time.

...Southern High Plains...
Weak but adequately moist, post-frontal upslope flow into the Raton
Mesa vicinity will favor widely scattered diurnal storm development
by mid-late afternoon. Modest west-northwesterly mid-level flow
will favor storms and their incipient outflow to the east-southeast
into the adjacent High Plains. Given the steep lapse rates and
relatively dry sub-cloud layer, evaporative cooling will probably
result in a few storms being capable of localized severe gusts
(60-80 mph).

..Smith/Bentley.. 08/05/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Aug 5 16:32:28 2026

ACUS01 KWNS 051632
SWODY1
SPC AC 051630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Wed Aug 05 2026

Valid 051630Z - 061200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL PLAINS INTO THE MID MISSISSIPPI VALLEY...ARIZONA...AND
THE SOUTHERN HIGH PLAINS...

...SUMMARY...
Isolated severe thunderstorms are possible today and tonight across
eastern Kansas into the mid Mississippi Valley. Isolated severe
gusts and hail may also occur across parts of the southern High
Plains and Arizona.

...Eastern Kansas into the Mid Mississippi Valley...
Severe potential this afternoon through tonight will be complicated
by ongoing convection/precipitation from eastern KS into the mid MS
Valley. In general, filtered daytime heating will occur along/ahead
of a surface front across these regions through the afternoon, with
this area on the southern periphery of mid/upper-level troughing
over central Canada and the northern Plains/Upper Midwest. An
embedded mid-level disturbance is aiding the ongoing sub-severe
convection. Current expectations are for at least isolated strong to
severe thunderstorms to develop later this afternoon and evening in
the gradually destabilizing airmass, with sufficient deep-layer
shear forecast to support some updraft organization. Occasional hail
and damaging winds may occur with the stronger cores, but evolution
into one or more bowing clusters remains uncertain. A stronger
signal exists for scattered to numerous thunderstorms to develop
late this evening into early Thursday morning across eastern KS into
MO in a strengthening low-level warm advection regime, with a
continued severe hail/wind threat possible given ample MUCAPE and
strong shear forecast in the cloud-bearing layer.

...Arizona...
A seasonably moist low-level airmass (with surface observations
generally in the low to mid 60s) will undergo further heating
through late afternoon. Orographic lift should favor convection
developing over the higher terrain and gradually spreading into the
lower deserts this evening, as modest mid-level easterly flow
persists to the south of upper ridging centered over the Southwest.
Very steep low to mid-level lapse rates will contribute to a risk
for strong downdrafts capable of producing at least isolated severe
gusts (60-80 mph). Considered adding a Slight Risk based on
scattered thunderstorm coverage moving into the lower deserts. But,
given ongoing cloud cover across parts of central/southeast AZ and a
tendency for the mid-level easterly flow to gradually weaken through
the evening, confidence in scattered severe gusts occurring remains
too low for an upgrade at this time.

...Southern High Plains...
Weak post-frontal low-level upslope flow into the Raton Mesa
vicinity will favor widely scattered convective development across
the southern High Plains by mid to late afternoon. Modest
west-northwesterly mid-level flow will favor motions to the
east-southeast into the adjacent High Plains along/near a surface
cold front. With steep lapse rates and a relatively dry sub-cloud
layer expected, evaporative cooling will probably result in a few
storms being capable of isolated severe gusts. A gust of 75+ mph may
occur given the very well mixed boundary layer. Isolated, marginally
severe hail may also occur with the initial cells that develop.

..Gleason/Lyons.. 08/05/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Aug 5 20:02:32 2026

ACUS01 KWNS 052002
SWODY1
SPC AC 052000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Wed Aug 05 2026

Valid 052000Z - 061200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE
CENTRAL PLAINS INTO THE MID MISSISSIPPI VALLEY...ARIZONA...AND
SOUTHERN HIGH PLAINS...

...SUMMARY...
Isolated severe thunderstorms are possible today and tonight across
eastern Kansas into the mid Mississippi Valley. Isolated severe
gusts and hail may also occur across parts of the southern High
Plains and Arizona.

...20Z Update...

...Eastern KS into the Mid MS Valley...
A low-amplitude shortwave trough continues to push through eastern
IA/northern MO, within the base of extensive upper troughing that
extends from western Canada through the northern/central Plains and
Upper Midwest/Upper Great Lakes into eastern Canada. Isolated strong
to severe storms are still expected this afternoon and evening
across the Mid MS Valley. Damaging gusts remain the primary risk but
a few instances of hail as possible as well.

Strengthening low to mid-level southerly flow is anticipated from
the southern High Plains through the Mid MO Valley overnight.
Associated warm-air advection will contribute to scattered to
numerous thunderstorms from eastern KS across central MO into
west-central IL. Elevated buoyancy and moderate to strong shear
within the cloud-bearing layer will support the potential strong to
severe storms capable of isolated large hail and damaging gusts.

...AZ...
Recent surface observations reveal a reservoir of low to mid 60s
dewpoints across southern AZ. Additional heating/mixing will likely
drop these dewpoints into the 50s later this afternoon, while also
eroding the remaining convective inhibition and supporting moderate
instability (i.e. MLCAPE from 1000 to 1500 J/kg). Given underlying
questions about convective evolution as the storms move west off the
high terrain, uncertainty regarding overall storm coverage and
intensity remains. This uncertainty precludes introducing higher
wind probabilities. That being said, the risk for isolated severe
gusts (60-80 mph) remains, particularly if a forward-propagating
line materializes.

...Southern High Plains...
Thunderstorm development is still anticipated across the higher
terrain of the Raton Meso before then progressing east-southeastward
into the adjacent High Plains. High cloud bases and steep low-level
lapse rates could result in a few strong to severe gusts,
particularly if updrafts intensify along a southward-progressing
cold front.

..Mosier.. 08/05/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Aug 05 2026/

...Eastern Kansas into the Mid Mississippi Valley...
Severe potential this afternoon through tonight will be complicated
by ongoing convection/precipitation from eastern KS into the mid MS
Valley. In general, filtered daytime heating will occur along/ahead
of a surface front across these regions through the afternoon, with
this area on the southern periphery of mid/upper-level troughing
over central Canada and the northern Plains/Upper Midwest. An
embedded mid-level disturbance is aiding the ongoing sub-severe
convection. Current expectations are for at least isolated strong to
severe thunderstorms to develop later this afternoon and evening in
the gradually destabilizing airmass, with sufficient deep-layer
shear forecast to support some updraft organization. Occasional hail
and damaging winds may occur with the stronger cores, but evolution
into one or more bowing clusters remains uncertain. A stronger
signal exists for scattered to numerous thunderstorms to develop
late this evening into early Thursday morning across eastern KS into
MO in a strengthening low-level warm advection regime, with a
continued severe hail/wind threat possible given ample MUCAPE and
strong shear forecast in the cloud-bearing layer.

...Arizona...
A seasonably moist low-level airmass (with surface observations
generally in the low to mid 60s) will undergo further heating
through late afternoon. Orographic lift should favor convection
developing over the higher terrain and gradually spreading into the
lower deserts this evening, as modest mid-level easterly flow
persists to the south of upper ridging centered over the Southwest.
Very steep low to mid-level lapse rates will contribute to a risk
for strong downdrafts capable of producing at least isolated severe
gusts (60-80 mph). Considered adding a Slight Risk based on
scattered thunderstorm coverage moving into the lower deserts. But,
given ongoing cloud cover across parts of central/southeast AZ and a
tendency for the mid-level easterly flow to gradually weaken through
the evening, confidence in scattered severe gusts occurring remains
too low for an upgrade at this time.

...Southern High Plains...
Weak post-frontal low-level upslope flow into the Raton Mesa
vicinity will favor widely scattered convective development across
the southern High Plains by mid to late afternoon. Modest
west-northwesterly mid-level flow will favor motions to the
east-southeast into the adjacent High Plains along/near a surface
cold front. With steep lapse rates and a relatively dry sub-cloud
layer expected, evaporative cooling will probably result in a few
storms being capable of isolated severe gusts. A gust of 75+ mph may
occur given the very well mixed boundary layer. Isolated, marginally
severe hail may also occur with the initial cells that develop.

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Aug 6 00:46:42 2026

ACUS01 KWNS 060046
SWODY1
SPC AC 060044

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0744 PM CDT Wed Aug 05 2026

Valid 060100Z - 061200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL PLAINS...OZARKS...MID MISSISSIPPI VALLEY...SOUTHERN HIGH
PLAINS AND SOUTHERN ARIZONA....

...SUMMARY...
Thunderstorms with severe wind gusts and hail will be possible this
evening in parts of the central Plains, Ozarks, mid Mississippi
Valley, southern High Plains and southern Arizona.

...Central Plains/Ozarks/Mid Mississippi Valley...
The latest water vapor imagery shows a broad area of cyclonic flow
over the north-central U.S., with an embedded shortwave trough in
the mid Mississippi Valley. At the surface, an ill-defined front is
located from far southern Kansas northeastward into Missouri and
Illinois. Scattered thunderstorms are ongoing on the cool side of
the boundary in northern Missouri. Along and to the south of the
front, surface dewpoints are in the 70s F, and the RAP has MLCAPE in
the 1500 to 2500 J/kg range. In addition, the WSR-88D VWP at St.
Louis has 0-6 km shear around 30 knots, and veering winds with
height in the lowest 1 Km above ground level. This environment will
be sufficient for isolated severe wind gusts and hail this evening.
However, forecast soundings have poor lapse rates which will keep
any severe threat localized.

...Southern High Plains...
Mid-level flow is west-northwesterly over much of the High Plains
this evening. A small pocket of moderate instability is analyzed by
the RAP over southeastern Colorado. Thunderstorms are ongoing to the
south of the instability max over northeastern New Mexico. These
storms will move east-southeastward into the northwestern Texas
Panhandle and western Oklahoma Panhandle this evening. MLCAPE around
1000 J/kg with 0-6 km shear in the 30 to 40 knot range, along with
steep low to mid-level lapse rates could be enough for isolated
severe gusts and hail.

...Southern Arizona...
The latest RAP analysis shows moderate instability over most of
southern Arizona, where MLCAPE is estimated in the 1000 to 2000 J/kg
range. Thunderstorms are developing in the higher terrain of eastern
Arizona, and these storms will move west-southwestward across
southern Arizona this evening. RAP forecast sounding at Tuscon early
this evening have 0-3 km lapse rates in the 8 to 8.5 C/km range,
along with surface temperature-dewpoint spreads exceeding 30 degrees
F. This will contribute to a potential for isolated severe gusts in
southern Arizona over the next few hours...see MCD 1838.

..Broyles.. 08/06/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Aug 6 05:48:34 2026

ACUS01 KWNS 060548
SWODY1
SPC AC 060546

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1246 AM CDT Thu Aug 06 2026

Valid 061200Z - 071200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHEAST KANSAS...NORTHEAST OKLAHOMA...SOUTHWEST MISSOURI AND FAR
NORTHWEST ARKANSAS...

...SUMMARY...
Thunderstorms with severe wind gusts and hail will be possible this
afternoon and evening over parts of Great Plains and Ozarks.
Isolated severe gusts will also be possible today from the
Mid-Atlantic northward into New York.

...Northern Oklahoma/Southern Kansas/Southwest Missouri/Far
Northwest Arkansas...
An upper-level trough will move eastward toward the mid Mississippi
Valley today. At the surface, a quasi-stationary front will be
located from far northern Oklahoma east-northeastward into
south-central Missouri, along which dewpoints will be in the 60s and
lower 70s F. As surface temperatures warm during the day, moderate
instability will develop along and near the front, with the RAP
forecasting MLCAPE to increase into the 2000 to 3000 J/kg range.
During the afternoon, low-level convergence will become focused near
the front with scattered thunderstorm development taking place from
southern Kansas into southwest Missouri. These storms will move
southeastward into northern Oklahoma and far northwestern Arkansas
by the early to mid evening.

In addition to the moderate instability, RAP forecast soundings
early this evening near the front have 0-6 km shear in the 35 to 40
knot range with 0-3 km lapse rates near 8 C/km. This environment
will support a severe threat. A mixed mode is expected with
supercells and multicell line segments both possible. Supercells
will be capable of severe wind gusts and hail, while the stronger
line segments will be associated with primarily a wind-damage
threat. The severe threat could persist into the mid to late
evening.

...Mid-Atlantic/New York/Far Western New England...
Mid-level flow will be southwesterly over the Northeast today. At
the surface, a trough will be located from the Atlantic Coastal
Plains of Virginia north-northeastward into the southeastern New
York. As surface temperatures warm today, thunderstorms will develop
in the foothills of the Appalachians, moving east-northeastward into
the lower elevations and toward the surface trough. Surface
dewpoints near the trough will be in the lower to mid 70s F, which
will contribute to moderate destabilization by early afternoon.
MLCAPE is forecast to peak in the 2000 to 3000 J/kg range, which
combined with steep low-level lapse rates will support an isolated
wind-damage threat.

...Western Nebraska/Southern South Dakota...
West-northwesterly mid-level flow will be in place over much of the north-central U.S. today. At the surface, an axis of low-level
moisture will set up from western Nebraska into far southern South
Dakota, where dewpoints will be in the 60s F. Near this axis, model
forecasts show a pocket of moderate instability this afternoon with
MLCAPE peaking in the 2000 to 3000 J/kg range. Although large-scale
ascent will be weak, any cell that can initiate near the instability
axis could be capable of producing isolated severe gusts.

..Broyles/Supinie.. 08/06/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Aug 6 12:25:06 2026

ACUS01 KWNS 061224
SWODY1
SPC AC 061223

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0723 AM CDT Thu Aug 06 2026

Valid 061300Z - 071200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NORTHEAST
OKLAHOMA AND SOUTHEAST KANSAS INTO THE MISSOURI OZARKS...

...SUMMARY...
Isolated to widely scattered severe thunderstorms capable primarily
of a severe-wind threat will be possible this afternoon and evening
over parts of Ozarks and Great Plains. Isolated strong to locally
severe gusts capable of wind damage are possible from the
Mid-Atlantic northward into New York.

...Ozarks westward into the southern High Plains...
Water-vapor imagery shows a mid-level anticyclone centered over
AZ/UT and a broad trough over the Upper Midwest favoring modest west-northwesterly mid to high-level flow across the central Plains.
Several clusters of showers/thunderstorms are ongoing this morning
from the mid MS Valley and lower MO Valley into the OK-KS border
region. Much of this activity is located to the north of a residual
front and outflow draped from the TX Panhandle east-northeast into
the mid MS Valley. South of the boundary, an appreciably moist
airmass, featuring 50s F dewpoints west to lower 70s east, will heat
in areas void of convection and related cloud debris. It is
uncertain how much influence morning showers/storms will have across
the Slight Risk area. Nonetheless, model forecast soundings show
moderate destabilization occurring by mid-late afternoon across much
of this region. Isolated to widely scattered storms will
preferentially develop near the effective front/outflow. Some storm organization is possible with the main threat being isolated to
widely scattered severe gusts. Have adjusted the level 1 intensity
for wind to northern OK westward into the southern High Plains where
steep low-level lapse rates are forecast. A couple of multicell
clusters may eventually evolve during the early evening. A relative
minimum in storm activity may occur over parts of the TX Panhandle
in between storms over the northeast NM/western part of the TX
Panhandle and higher coverage of storms farther east over northern
OK into the Ozarks.

...Mid-Atlantic into the Northeast...
Mid-level flow will be southwesterly over the Northeast today. At
the surface, a trough will be located from the Atlantic Coastal
Plains of Virginia north-northeastward into the southeastern New
York. As surface temperatures warm today, thunderstorms will
develop in the foothills of the Appalachians, moving
east-northeastward into the lower elevations and toward the surface
trough. Surface dewpoints near the trough will be in the lower to
mid 70s F, which will contribute to moderate destabilization by
early afternoon (MLCAPE 1000-2500 J/kg). Some of the stronger
water-loaded downdrafts will be capable of an isolated risk for wind
damage.

...Western Nebraska/southern South Dakota...
West-northwesterly mid-level flow will be in place over much of the north-central U.S. At the surface, an axis of low-level
moisture will set up from western Nebraska into far southern South
Dakota, where dewpoints will be in the 60s F. Near this axis, model
forecasts show a pocket of moderate instability this afternoon with
MLCAPE around 2000 J/kg. Although large-scale ascent will be weak,
any cell that can initiate near the instability axis could be
capable of producing isolated severe gusts/large hail.

..Smith/Bentley.. 08/06/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Aug 6 16:32:12 2026

ACUS01 KWNS 061631
SWODY1
SPC AC 061630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Thu Aug 06 2026

Valid 061630Z - 071200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN/CENTRAL PLAINS INTO THE OZARKS...THE CAROLINAS INTO THE MID-ATLANTIC AND NORTHEAST...AND FAR NORTHEAST COLORADO INTO PARTS
OF NEBRASKA AND SOUTHERN SOUTH DAKOTA...

...SUMMARY...
Generally isolated strong to severe thunderstorms capable of
producing hail and damaging winds appear possible across parts of
the southern/central Plains into the Ozarks. Isolated strong to
locally severe gusts capable of wind damage may also occur from
parts of the Carolinas into the Mid-Atlantic and Northeast.

...Southern/Central Plains into the Ozarks...
Ongoing convection in MO and along the KS/OK border late this
morning has been aided by modest low-level warm/moist advection in
the vicinity of a slow-moving surface boundary. Current expectations
are for gradual destabilization to occur through the afternoon
along/south of this boundary from the southern High Plains eastward
to parts of the Ozarks. This region will remain on the southern
periphery of large-scale troughing centered over Canada and the
northern Plains, with nebulous/weak forcing for ascent evident along
the surface front. This leads to low confidence in renewed
thunderstorms later this afternoon into the evening. Based on this
and trends in 12Z guidance, have removed the Slight Risk for
severe/damaging winds. Still, an isolated hail/wind threat remains
apparent along the length of this boundary, as moderate instability
and sufficient deep-layer shear will be present to support updraft
organization with any cells that can form/be sustained. A greater
signal for scattered thunderstorm development exists this
evening/overnight across parts of KS/MO as a low-level jet gradually strengthens in this time frame. Have expanded severe hail/wind
probabilities northward a bit to account for this potential.

...Carolinas into the Mid-Atlantic and Northeast...
Around 20-35 kt of southwesterly mid-level flow will exist over
parts of the Mid-Atlantic into the Northeast today. At the surface,
a weak trough will be located from the coastal VA
north-northeastward into eastern NY. As surface temperatures
continue to warm into the 80s with filtered daytime heating,
thunderstorms will develop in the foothills of the Appalachians and subsequently move east-northeastward into the lower elevations and
toward the surface trough. While mid-level lapse rates will remain
poor, a rather moist low-level airmass will contribute to moderate
instability this afternoon (MLCAPE generally 1000-2500 J/kg).
Greater instability and steeper low-level lapse rates are forecast
with southward extent into the western Carolinas where mid-level
flow will be comparatively weaker. Some of the stronger water-loaded
downdrafts will be capable of producing occasional damaging winds.

...Colorado/Nebraska/South Dakota...
West-northwesterly mid-level flow will persist over much of the
north-central CONUS through the period. At the surface, an axis of
greater low-level moisture will exist from northeast CO/western NE
into southern SD along/east of a weak surface trough, where
dewpoints will generally be in the 60s. Near this axis, latest
NAM/RAP forecasts show a narrow corridor of moderate instability
this afternoon, with MLCAPE up to 2000-2500 J/kg. Although
large-scale ascent will remain weak/nebulous across this region, any
cell that can initiate near the instability axis would be capable of
producing isolated severe gusts/large hail. Have therefore
maintained the Marginal Risk across this region with some expansion.
But, given low confidence in convective initiation, refrained from
including greater severe wind/hail probabilities at this time.

..Gleason/Lyons.. 08/06/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Aug 6 20:01:38 2026

ACUS01 KWNS 062001
SWODY1
SPC AC 061959

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0259 PM CDT Thu Aug 06 2026

Valid 062000Z - 071200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN/CENTRAL PLAINS INTO THE OZARKS...THE CAROLINAS INTO THE MID-ATLANTIC AND NORTHEAST...AND FAR NORTHEAST COLORADO INTO PARTS
OF NEBRASKA AND SOUTHERN SOUTH DAKOTA...

...SUMMARY...
Isolated strong to severe thunderstorms capable of producing hail
and damaging winds are possible across parts of the southern/central
Plains into the Ozarks. Isolated damaging wind gusts may also occur
from parts of the Carolinas into the Mid-Atlantic and Northeast.

...20Z Update...
The forecast remains on track, and only minor adjustments were made
with this update. In the near term, the primary concern will be the
potential for a few organized storms in southern MO capable of
producing severe hail and damaging wind gusts. See MCD 1843 more
details.

..Weinman.. 08/06/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Aug 06 2026/

...Southern/Central Plains into the Ozarks...
Ongoing convection in MO and along the KS/OK border late this
morning has been aided by modest low-level warm/moist advection in
the vicinity of a slow-moving surface boundary. Current expectations
are for gradual destabilization to occur through the afternoon
along/south of this boundary from the southern High Plains eastward
to parts of the Ozarks. This region will remain on the southern
periphery of large-scale troughing centered over Canada and the
northern Plains, with nebulous/weak forcing for ascent evident along
the surface front. This leads to low confidence in renewed
thunderstorms later this afternoon into the evening. Based on this
and trends in 12Z guidance, have removed the Slight Risk for
severe/damaging winds. Still, an isolated hail/wind threat remains
apparent along the length of this boundary, as moderate instability
and sufficient deep-layer shear will be present to support updraft
organization with any cells that can form/be sustained. A greater
signal for scattered thunderstorm development exists this
evening/overnight across parts of KS/MO as a low-level jet gradually strengthens in this time frame. Have expanded severe hail/wind
probabilities northward a bit to account for this potential.

...Carolinas into the Mid-Atlantic and Northeast...
Around 20-35 kt of southwesterly mid-level flow will exist over
parts of the Mid-Atlantic into the Northeast today. At the surface,
a weak trough will be located from the coastal VA
north-northeastward into eastern NY. As surface temperatures
continue to warm into the 80s with filtered daytime heating,
thunderstorms will develop in the foothills of the Appalachians and subsequently move east-northeastward into the lower elevations and
toward the surface trough. While mid-level lapse rates will remain
poor, a rather moist low-level airmass will contribute to moderate
instability this afternoon (MLCAPE generally 1000-2500 J/kg).
Greater instability and steeper low-level lapse rates are forecast
with southward extent into the western Carolinas where mid-level
flow will be comparatively weaker. Some of the stronger water-loaded
downdrafts will be capable of producing occasional damaging winds.

...Colorado/Nebraska/South Dakota...
West-northwesterly mid-level flow will persist over much of the
north-central CONUS through the period. At the surface, an axis of
greater low-level moisture will exist from northeast CO/western NE
into southern SD along/east of a weak surface trough, where
dewpoints will generally be in the 60s. Near this axis, latest
NAM/RAP forecasts show a narrow corridor of moderate instability
this afternoon, with MLCAPE up to 2000-2500 J/kg. Although
large-scale ascent will remain weak/nebulous across this region, any
cell that can initiate near the instability axis would be capable of
producing isolated severe gusts/large hail. Have therefore
maintained the Marginal Risk across this region with some expansion.
But, given low confidence in convective initiation, refrained from
including greater severe wind/hail probabilities at this time.

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Aug 7 01:03:08 2026

ACUS01 KWNS 070102
SWODY1
SPC AC 070101

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0801 PM CDT Thu Aug 06 2026

Valid 070100Z - 071200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE OKLAHOMA AND TEXAS PANHANDLES...

...SUMMARY...
Isolated to scattered strong to severe thunderstorms capable of
producing hail and damaging winds are possible across parts of the
southern Plains into the Ozarks this evening and overnight. More
isolated strong to severe thunderstorms are possible across portions
of the central Plains and Mid-Atlantic/Northeast this evening.

...Southern Plains/Ozarks...
Clusters of isolated to scattered thunderstorms will continue to
emerge across southern Plains and portions of the Ozarks this
evening and into the overnight hours. Recent radar mosaics and
surface observations show the gradual decay of a cluster across
southwest MO as the attendant cold pool continues to expand and
undercut convection. Some lingering hail, and perhaps damaging wind,
threat will persist with this activity through roughly 03-05 UTC
given the proximity to ample buoyancy and modest deep-layer wind
shear on the south/southwest flank of the cold pool.

Further west, thunderstorm development is ongoing across southwest
KS and southeast CO along zones of low-level confluence. Additional thunderstorm development is anticipated through late evening as
convection continues to cluster and grow upscale in tandem with an
increase in the nocturnal jet. The past several runs of the HRRR and
RRFS both depict the emergence of a loosely organized MCS across
this region with the potential for significant wind gusts. Given the
trends in both satellite/radar and model guidance, confidence is
sufficiently high to introduce focused 15% wind probabilities.

Additional thunderstorm development is expected across the greater
Emporia, KS area later this evening on the eastern periphery of the
nocturnal jet and along the western edge of the MO cold pool. Steep
lapse rates and sufficient deep-layer shear will support organized
convection that will likely pose a threat for large hail, and
perhaps sporadic downburst winds. A secondary corridor of higher
severe potential may emerge across eastern KS overnight, but the
expectation for clustered storm modes should act to modulate storm longevity/intensity and precludes higher probabilities.

...Eastern North Dakota into northwest Minnesota...
Convection developing along a pre-frontal trough in southeast ND and
northern MN has exhibited periods of strong VII and cold cloud-top
temperatures indicative of severe convection. This activity has
mainly been focused within a corridor of low to mid 60s dewpoints
where effective bulk shear is around 35-40 knots and MLCAPE is
likely between 1500-2500 J/kg, based on a combination of RAP
mesoanalyses and by modifying the 00 UTC ABR RAOB. Latest guidance
has hinted that additional convection is possible overnight as a
cloud front pushes east and impinges on this narrow, but unstable,
warm sector.

...Carolinas into the Mid-Atlantic...
Isolated clusters of strong thunderstorms remain across the region
as of 01 UTC. However, most convection has exhibited signs of
gradual weakening over the past two hours. Although some localized
damaging wind threat may linger for the next hour or so, continued
nocturnal stabilization should further limit thunderstorm coverage
and intensity and warrants a removal of risk probabilities.

...Western Nebraska/South Dakota...
A few attempts at sustained convection have been noted over the past
few hours across western SD along a weak surface trough. With the
passage of the upper trough axis and the onset of nocturnal cooling
expected over the next few hours, the potential for thunderstorm
development appears very limited.

..Moore.. 08/07/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Aug 7 05:53:44 2026

ACUS01 KWNS 070553
SWODY1
SPC AC 070551

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1251 AM CDT Fri Aug 07 2026

Valid 071200Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-ATLANTIC...

...SUMMARY...
Isolated to scattered strong to severe thunderstorms capable of
producing damaging winds are expected across portions of the
Mid-Atlantic this afternoon. More isolated severe thunderstorms are
expected from the mid-Missouri Valley into the Lake Superior region
as well as across parts of the southern High Plains and central
Plains.

...Synopsis...
00 UTC upper-air analyses and latest GOES water-vapor imagery depict
several perturbations within a low-amplitude upper trough in place
over the central CONUS. The first of these perturbations is analyzed
over the mid-MS Valley and is expected to migrate east towards the
Mid-Atlantic region by mid-afternoon. A more pronounced shortwave
trough is evident over central Canada into the northern Plains. This
feature, along with an attendant surface low and trailing cold
front, will move eastward through the day, reaching the Great Lakes
region by tonight. Strong to severe thunderstorm chances will
primarily be associated with these synoptic features, though more
localized corridors of strong/severe thunderstorms may emerge across
the southern High Plains and parts of the Ozarks associated with
outflow boundaries from ongoing convection.

...Mid-Atlantic...
The weak upper perturbation currently over the MS Valley is forecast
to reach the central Appalachians/Mid-Atlantic region by
mid-afternoon. Strong heating of an seasonally moist air mass
(dewpoints in the low to mid 70s) will compensate for otherwise
meager mid-level lapse rates and support MLCAPE values of 1000-2000
J/kg with minimal capping by early afternoon. A combination of weak
synoptic lift aided by localized orographic ascent should promote
isolated to scattered thunderstorm development during the 18-20 UTC
period. Most CAM guidance depicts a reasonably strong signal for
thunderstorm clustering and upscale growth as storms spread
northeast towards the I-95 corridor around peak heating. Although
winds through the lowest 2-3 km will remain fairly modest, steep
low-level lapse rates and around 25 knots of effective bulk shear
should promote loosely organized clusters/lines with embedded swaths
of damaging winds.

...Mid-Missouri Valley into the Lake Superior region...
Thunderstorm development along the cold front is expected early this
morning, possibly as early as 12-14 UTC across portions of eastern
MN. This early activity will likely be elevated in nature, but 30-35
knot mid-level flow should support adequate hodograph elongation for
a few organized cells capable of severe hail. With time, diurnal heating/destabilization downstream and persistent forcing along the
front should promote steady intensification and upscale growth of
convection with a transition to primarily a wind risk across WI and
the Upper Peninsula of MI. Further south, more isolated thunderstorm
coverage across southern MN, IA, and eastern NE may support a
supercell or two with an attendant threat for large hail as well as
severe wind.

...Southern High Plains into the Ozarks...
Isolated thunderstorms are expected to develop across northeast NM
into the TX Panhandle this afternoon - driven by either orographic
ascent along the Sange de Cristo mountains and/or the Raton Mesa or
lift along a residual outflow boundary associated with an ongoing,
but fairly confined, MCS across the northern TX Panhandle (as of 06
UTC). Regardless of the forcing mechanism, convection developing
across this region will mature in an environment featuring fairly
weak wind shear, but a deeply-mixed boundary layer conducive for
severe downbursts. Despite considerable variance in storm placement
and coverage in latest CAM ensembles, the consistent signal for
severe downbursts warrants low-end severe wind probabilities.

Further east into eastern OK and the Ozarks, a focused corridor of thunderstorms will likely emerge on the outflow boundary of a
convective cluster developing across eastern KS (as of 06 UTC). Some
CAM solutions hint that sporadic large hail and/or damaging
downbursts will be possible with this activity, but considerable
uncertainty on where and how intense this activity will be limits
confidence on introducing additional risk areas.

...Nebraska/South Dakota...
Elevated convection is expected to develop across portions of
northern NE and southern SD during the overnight hours tonight as
isentropic ascent increases in tandem with a modest intensification
of a low-level jet. Low-level moistening through 850 mb under a
plume of 7-8 C/km mid-level lapse rates should promote a adequate
buoyancy few robust updrafts (though confidence in storm coverage is
limited due to the weak nature of the forcing for ascent). However,
strong shear across the region will likely promote organized
convection, including a supercell or two, capable of producing large
hail.

..Moore/Marsh.. 08/07/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Aug 7 12:36:44 2026

ACUS01 KWNS 071236
SWODY1
SPC AC 071234

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0734 AM CDT Fri Aug 07 2026

Valid 071300Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE MID-ATLANTIC...

...SUMMARY...
Thunderstorms capable of scattered damaging wind gusts are possible
this afternoon and early evening over parts of the Mid-Atlantic
states. Isolated severe thunderstorms are also possible across
portions of the central U.S. and Arizona.

...Mid-Atlantic...
A relatively nondescript pattern is located over the region between
a Bermuda high and troughing over the Upper Midwest. Seasonably
strong heating of a moist airmass (12 UTC Dulles, VA raob sampled a
14 g/kg lowest 100-mb mean mixing ratio) will support a
destabilizing boundary layer and scattered thunderstorm development
this afternoon. A few thunderstorm clusters will probably evolve
through the late afternoon into the early evening as this activity
moves through the I-95 corridor. Isolated strong to locally severe
gusts (i.e., 50-60 mph) capable of scattered wind damage will be the
primary threat with the stronger cores.

...Mid-Missouri Valley into the Lake Superior region...
Water-vapor imagery this morning shows a mid-level shortwave trough
moving southeastward over the Red River Valley towards the Upper
Great Lakes later today. In response to forcing for ascent
associated with the disturbance, a couple of ongoing thunderstorm
clusters will probably continue this morning. There is low
confidence in the evolution of these clusters and an associated
severe risk. Nonetheless, as a cold front continues to push
southeast across the Upper Midwest later today, additional storm
development is likely but details are nebulous at this time. Model
guidance indicates a greater overlap of CAPE/shear may focus across
western IA later this afternoon. Will re-evaluate in subsequent
outlook updates for whether a mesoscale corridor can be identified
with a locally greater severe risk within the larger Marginal Risk
denoting isolated hail/wind potential.

...Southern High Plains into the Ozarks...
Isolated thunderstorms are expected to develop across northeast NM
into the TX Panhandle this afternoon. Relatively high uncertainty
remains regarding storm placement removed from the higher terrain of
northeast NM. Regardless, ample heating of an adequately moist but
deepening boundary layer will support a thermodynamic profile
favoring severe gusts with the stronger cores and associated
outflow.

Further east into OK, KS, and the Ozarks, ongoing elevated storms
from northern OK into eastern KS are likely rooted near the base of
the EML. This activity will probably diminish in spatial extent
through midday, but it is possible additional storms will develop
along the outflow and could yield localized strong/severe storm
potential. Will defer severe highlights at this time due to low predictability.

...Arizona...
Latest convection-allowing model ensembles and MPAS guidance imply
some risk for widely scattered storms to develop over the Mogollon
Rim and the higher terrain in southeast AZ and gradually spread into
the lower deserts this evening. Given the steep lapse rates
preceding this potential convection and possible scenario, have
introduced low-severe wind probabilities.

...Nebraska/South Dakota...
Elevated convection is expected to develop across portions of
northern NE and southern SD during the overnight hours tonight as
isentropic ascent increases in tandem with a modest intensification
of a low-level jet. Low-level moistening through 850 mb under a
plume of 7-8 C/km mid-level lapse rates should promote adequate
buoyancy for a few robust updrafts (though confidence in storm
coverage is limited due to the weak nature of the forcing for
ascent). However, strong shear across the region will likely promote
organized convection, including a supercell or two, capable of
producing large hail.

..Smith/Kerr.. 08/07/2026

$$

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From COD Weather Processor @1:2320/107 to All on Fri Aug 7 16:08:42 2026

ACUS01 KWNS 071608
SWODY1
SPC AC 071606

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1106 AM CDT Fri Aug 07 2026

Valid 071630Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHERN MINNESOTA INTO IOWA...NORTHERN WISCONSIN INTO THE UPPER
PENINSULA OF MICHIGAN...AND THE MID-ATLANTIC...

...SUMMARY...
Isolated to scattered severe thunderstorms are possible across parts
of the Upper Midwest/Great Lakes this afternoon and evening, with
large to very large hail and severe winds the main threats.
Thunderstorms capable of scattered damaging winds may also occur
over portions of the Mid-Atlantic.

...Upper Midwest/Great Lakes...
Thunderstorms are ongoing along/ahead of a cold front late this
morning from the MN Arrowhead southwestward into southern
MN/northern IA. While there are still uncertainties regarding
convective evolution this afternoon and evening, it appears
increasingly probable that two mesoscale corridors of greater severe
potential will exist: one across southern MN into IA, and another
across northern WI into the U.P of MI. In general, the severe risk
today will be aided by a mid/upper-level trough advancing
east-southeastward across these regions in tandem with a 35-50 kt west-northwesterly mid-level jet.

Thunderstorms are expected to further increase in coverage and
intensity along the eastward-advancing cold front this afternoon
across parts of northern WI into the western U.P of MI. While latest
NAM/RAP forecast soundings across this area suggest low-level
moisture remains fairly shallow/limited, mostly clear conditions are
noted on recent visible satellite imagery. Resultant moderate
instability and gradually strengthening deep-layer shear with the
approach of the mid/upper-level trough will aid in thunderstorm
organization. Small clusters/bowing line segments will probably be
the dominant mode given the linear forcing of the cold front, with
enhanced low/mid-level flow aiding the risk for scattered
severe/damaging winds. A Slight Risk has been added for parts of
northern WI into the U.P of MI given increased confidence in this
scenario occurring.

Farther south, generally elevated convection is ongoing across
southern MN into northern IA. The 12Z observed sounding from MPX
showed fairly steep low/mid-level lapse rates in the 850-530 mb
layer, which along with 35-40 kt of effective bulk shear and around
2000 J/kg of MUCAPE may continue to support a threat for severe hail
with this activity in the short term. Even though cloud cover
remains prevalent across these areas late this morning, a corridor
of moderate to locally strong instability is still forecast to
develop this afternoon across parts of eastern NE into IA ahead of
the cold front. Current expectations are for multiple surface-based
supercells and/or bowing clusters to develop along/ahead of the
front in southern MN, and then spread southeastward across IA
through the late afternoon/early evening. A threat for both large
hail and damaging winds should exist with this activity, and a
Slight Risk has been introduced where confidence is greater that
robust convection will occur. 2+ inch diameter hail and perhaps a
tornado also appear possible with any surface-based supercell, even
though low-level flow will not be overly strong.

...Ohio Valley into the Mid-Atlantic...
Between upper troughing over central Canada/the Upper Midwest and
upper ridging over the western Atlantic, around 20-30 kt of
southwesterly mid-level flow will exist today from the OH Valley
into the Mid-Atlantic and Northeast. Greater destabilization and
steepening of low-level lapse rates are anticipated this afternoon
across the Mid-Atlantic, where recent visible satellite imagery
shows generally clear skies. Loosely organized cells/clusters that
initially develop across the higher terrain of the central
Appalachians should spread into the Mid-Atlantic coastal plain
through the afternoon/evening, while posing a threat for scattered
damaging winds up to 50-60 mph and perhaps marginally severe hail.
Across the OH Valley, somewhat weaker mid-level flow may tend to
limit updraft organization. Still, some potential for clustering and
isolated damaging winds may exist downstream of ongoing convection
where greater destabilization can ocur. Have therefore expanded the
Marginal Risk across much of the OH Valley to account for this
possibility.

...Southern/Central Plains into the Ozarks...
Elevated thunderstorms posing an isolated hail threat in southeast
KS late this morning should further diminish into the early
afternoon as a southwesterly low-level jet gradually weakens. To the
south and east of this activity, a hot and unstable airmass will
exist this afternoon across OK into parts of southern MO and AR.
Although details regarding convective evolution remain unclear, it
is possible that robust thunderstorms develop/continue on the
outflow from this morning's activity, or near multiple MCVs present
from earlier convection. Isolated strong to severe winds appear
possible, even though deep-layer shear should remain weak. The
Marginal Risk has been expanded eastward and connected to the risk
area in the OH Valley. Other isolated thunderstorms posing some
severe wind threat may develop this afternoon farther west across
eastern NM into the OK/TX Panhandles.

...Arizona...
Modest east-southeasterly mid-level flow will persist today over AZ
to the south of a mid/upper-level anticyclone centered over the Four
Corners. Widely scattered convection should develop over the
Mogollon Rim and the higher terrain in southeast AZ this afternoon,
and gradually spread into the lower deserts this evening. Given the
very well-mixed boundary layer and weak to locally moderate
instability expected to be in place ahead of these thunderstorms,
have maintained low severe wind probabilities.

...Northern Nebraska/Southern South Dakota...
Elevated thunderstorms may develop across parts of northern NE and
southern SD late tonight/early Saturday morning as isentropic ascent
increases in tandem with modest strengthening of a southerly
low-level jet. Low-level moistening beneath steepening mid-level
lapse rates should support sufficient MUCAPE for robust updrafts,
although confidence in overall coverage remains low due to
weak/nebulous large-scale ascent. Regardless, strong shear in the
cloud-bearing layer across this area should promote organized
convection capable of producing isolated severe hail.

..Gleason/Weinman.. 08/07/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Aug 7 19:27:52 2026

ACUS01 KWNS 071927
SWODY1
SPC AC 071925

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0225 PM CDT Fri Aug 07 2026

Valid 072000Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF IOWA...NORTHERN WISCONSIN INTO THE UPPER PENINSULA OF MICHIGAN...AND
THE MID-ATLANTIC...

...SUMMARY...
Isolated to scattered severe thunderstorms are possible across parts
of the Upper Midwest/Great Lakes this afternoon and evening, with
large to very large hail and severe winds the main threats.
Thunderstorms capable of scattered damaging winds may also occur
over portions of the Mid-Atlantic.

...20z Update...
Adjustments were made to the D1 Convective Outlook to trim
probabilities behind the cold front across Minnesota/Iowa and behind morning/early afternoon convection across Kansas/Oklahoma. The
Marginal Risk was shifted southward across Oklahoma/Arkansas to
account for recent trends in storm/outflow evolution and resulting
increasing potential for damaging wind downstream.

A Marginal Risk was added across portions of southwestern New Mexico
into far western Texas. Across this region, a very deeply mixed and
hot boundary layer will support outflow dominant storms. Hi-res
guidance suggests that storms may produce strong to severe outflow
winds across this region later this afternoon.

See previous discussion below for more information.

..Thornton.. 08/07/2026

.PREV DISCUSSION... /ISSUED 1106 AM CDT Fri Aug 07 2026/

...Upper Midwest/Great Lakes...
Thunderstorms are ongoing along/ahead of a cold front late this
morning from the MN Arrowhead southwestward into southern
MN/northern IA. While there are still uncertainties regarding
convective evolution this afternoon and evening, it appears
increasingly probable that two mesoscale corridors of greater severe
potential will exist: one across southern MN into IA, and another
across northern WI into the U.P of MI. In general, the severe risk
today will be aided by a mid/upper-level trough advancing
east-southeastward across these regions in tandem with a 35-50 kt west-northwesterly mid-level jet.

Thunderstorms are expected to further increase in coverage and
intensity along the eastward-advancing cold front this afternoon
across parts of northern WI into the western U.P of MI. While latest
NAM/RAP forecast soundings across this area suggest low-level
moisture remains fairly shallow/limited, mostly clear conditions are
noted on recent visible satellite imagery. Resultant moderate
instability and gradually strengthening deep-layer shear with the
approach of the mid/upper-level trough will aid in thunderstorm
organization. Small clusters/bowing line segments will probably be
the dominant mode given the linear forcing of the cold front, with
enhanced low/mid-level flow aiding the risk for scattered
severe/damaging winds. A Slight Risk has been added for parts of
northern WI into the U.P of MI given increased confidence in this
scenario occurring.

Farther south, generally elevated convection is ongoing across
southern MN into northern IA. The 12Z observed sounding from MPX
showed fairly steep low/mid-level lapse rates in the 850-530 mb
layer, which along with 35-40 kt of effective bulk shear and around
2000 J/kg of MUCAPE may continue to support a threat for severe hail
with this activity in the short term. Even though cloud cover
remains prevalent across these areas late this morning, a corridor
of moderate to locally strong instability is still forecast to
develop this afternoon across parts of eastern NE into IA ahead of
the cold front. Current expectations are for multiple surface-based
supercells and/or bowing clusters to develop along/ahead of the
front in southern MN, and then spread southeastward across IA
through the late afternoon/early evening. A threat for both large
hail and damaging winds should exist with this activity, and a
Slight Risk has been introduced where confidence is greater that
robust convection will occur. 2+ inch diameter hail and perhaps a
tornado also appear possible with any surface-based supercell, even
though low-level flow will not be overly strong.

...Ohio Valley into the Mid-Atlantic...
Between upper troughing over central Canada/the Upper Midwest and
upper ridging over the western Atlantic, around 20-30 kt of
southwesterly mid-level flow will exist today from the OH Valley
into the Mid-Atlantic and Northeast. Greater destabilization and
steepening of low-level lapse rates are anticipated this afternoon
across the Mid-Atlantic, where recent visible satellite imagery
shows generally clear skies. Loosely organized cells/clusters that
initially develop across the higher terrain of the central
Appalachians should spread into the Mid-Atlantic coastal plain
through the afternoon/evening, while posing a threat for scattered
damaging winds up to 50-60 mph and perhaps marginally severe hail.
Across the OH Valley, somewhat weaker mid-level flow may tend to
limit updraft organization. Still, some potential for clustering and
isolated damaging winds may exist downstream of ongoing convection
where greater destabilization can ocur. Have therefore expanded the
Marginal Risk across much of the OH Valley to account for this
possibility.

...Southern/Central Plains into the Ozarks...
Elevated thunderstorms posing an isolated hail threat in southeast
KS late this morning should further diminish into the early
afternoon as a southwesterly low-level jet gradually weakens. To the
south and east of this activity, a hot and unstable airmass will
exist this afternoon across OK into parts of southern MO and AR.
Although details regarding convective evolution remain unclear, it
is possible that robust thunderstorms develop/continue on the
outflow from this morning's activity, or near multiple MCVs present
from earlier convection. Isolated strong to severe winds appear
possible, even though deep-layer shear should remain weak. The
Marginal Risk has been expanded eastward and connected to the risk
area in the OH Valley. Other isolated thunderstorms posing some
severe wind threat may develop this afternoon farther west across
eastern NM into the OK/TX Panhandles.

...Arizona...
Modest east-southeasterly mid-level flow will persist today over AZ
to the south of a mid/upper-level anticyclone centered over the Four
Corners. Widely scattered convection should develop over the
Mogollon Rim and the higher terrain in southeast AZ this afternoon,
and gradually spread into the lower deserts this evening. Given the
very well-mixed boundary layer and weak to locally moderate
instability expected to be in place ahead of these thunderstorms,
have maintained low severe wind probabilities.

...Northern Nebraska/Southern South Dakota...
Elevated thunderstorms may develop across parts of northern NE and
southern SD late tonight/early Saturday morning as isentropic ascent
increases in tandem with modest strengthening of a southerly
low-level jet. Low-level moistening beneath steepening mid-level
lapse rates should support sufficient MUCAPE for robust updrafts,
although confidence in overall coverage remains low due to
weak/nebulous large-scale ascent. Regardless, strong shear in the
cloud-bearing layer across this area should promote organized
convection capable of producing isolated severe hail.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Aug 8 00:47:16 2026

ACUS01 KWNS 080047
SWODY1
SPC AC 080045

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 PM CDT Fri Aug 07 2026

Valid 080100Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
SOUTHERN IOWA...AND THE UPPER GREAT LAKES...

...SUMMARY...
Isolated severe thunderstorms remain possible across parts of the
Upper Midwest/Great Lakes this evening, with large hail and severe
winds the main threats. The severe risk should gradually decrease
through 05z (midnight local time).

...Iowa into northern Wisconsin/U.P. of Michigan...

Isolated strong to severe thunderstorms continue this evening across
parts of IA and the U.P. of MI ahead of a surface cold front. Some
additional re-development may occur along the front across
central/southern IA over the next few hours, while convection
further north gradually decreases in intensity over the next couple
of hours. Isolated large hail and strong/locally damaging wind gusts
remain possible. Reference MCD 1857 for more information.

Further south, severe probabilities were trimmed across portions of
the MO Valley, where thunderstorm potential appears limited
overnight.

...AZ/NM into the TX Panhandle...

Isolated strong to severe thunderstorms will persist for a few more
hours across parts of eastern NM into the TX Panhandle and far
west-central OK. Severe wind gusts will be the main hazards with
this activity given the hot, well-mixed boundary layer. Some of the
stronger storms could sporadically produce large hail. Overall
severe risk should gradually wane with loss of daytime heating after
03z.

Further southwest, isolated thunderstorms moving off higher terrain
into portions of southern AZ and southwest NM will pose a risk for
strong wind gusts the next few hours. Storm coverage currently is
fairly sparse, and it is uncertain if sufficient clustering will
occur and spread west/southwest into lower elevations. Given
uncertainty, will maintain the Marginal (level 1 of 5) risk.

...Ozark Plateau...

Widely scattered thunderstorms will continue for a few more hours
this evening within the moderately unstable environment. Locally
damaging wind gusts will be possible, but thunderstorm intensity
should gradually wane over the next 1-3 hours. Reference MCD 1858
for more information.

...SD/NE...

A conditional large hail risk remains late tonight/early Saturday
across parts of southern SD into northern NE. Forecast guidance
still suggests isolated elevated thunderstorms will develop within a
corridor of favorable elevated instability and 35+ kt effective
shear magnitudes. If storms develop, large hail will be possible.

...OH Valley into the Mid-Atlantic...

Locally gusty winds may continue another hour or two with a
thunderstorm cluster of WV and another cluster in CT. Thunderstorm
activity may persist across parts of the Midwest toward the
Mid-Atlantic beyond 02-03z, but overall severe potential is expected
to largely be diminished by then due to loss of daytime and
increasing boundary layer stabilization.

..Leitman.. 08/08/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Aug 8 04:55:14 2026

ACUS01 KWNS 080455
SWODY1
SPC AC 080453

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1153 PM CDT Fri Aug 07 2026

Valid 081200Z - 091200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE NORTHERN AND CENTRAL PLAINS INTO THE UPPER MISSISSIPPI
VALLEY...PARTS OF THE MID-ATLANTIC...AND SOUTHERN ARIZONA...

...SUMMARY...
Severe thunderstorms will be possible this afternoon and evening
across parts of the central and northern Plains southeastward into
the lower to mid Missouri Valley. Additional strong to severe storms
are possible in the Mid-Atlantic and central/southern Arizona.

...Northern/Central Plains into MN/IA/MO...

A modest but weakening low-level jet across portions of NE/SD may
support ongoing elevated convection this morning, mainly across NE.
This activity will weaken and spread southeast through the morning
hours, but could pose a marginal risk for hail.

The forecast for the afternoon into nighttime hours becomes complex
and uncertain. Broad northwesterly flow aloft will modestly
strengthen by late afternoon/early evening as several shortwave
impulses migrate through the base of an upper low/trough centered
over central Canada. Height falls are expected to be weak, and warm
mid-level temperatures will pose capping issues. Nevertheless,
surface troughing across the northern/central High Plains will
result in south/southeasterly low-level flow, transporting 60s F
dewpoints northward across the central Plains and MO Valley ahead of
a southward sagging surface front oriented across ND and northern MN
late in the period. Increasing boundary layer moisture beneath steep
midlevel lapse rates will support moderate to strong
destabilization.

Several areas of convection may develop during the late
afternoon/evening near the surface trough, and overnight near the southward-sagging surface front. Given weak large-scale ascent and
warm midlevels, it remains uncertain where storm development is most
likely and how storm coverage will evolve. With an increasing
low-level jet across the central Plains during the nighttime hours,
some convection could develop atop a capping inversion, or along the
surface front near the ND/SD border. Isolated large hail is possible
with this activity. If surface-based convection can develop within
the strongly unstable airmass, damaging wind gusts also will be
possible.

Additional high-based convection is possible across CO and western
KS/NE. A hot and well mixed boundary layer could support strong
outflow winds with this activity as well.

...Mid-Atlantic...

A modest midlevel shortwave trough will overspread the region
through afternoon/early evening. Strong heating of a seasonally
moist airmass will support moderate instability. Vertical shear is
expected to be sufficient for organized cells and clusters with an
attendant risk for damaging wind gusts. The strongest cells could
also produce small hail.

...AZ...

Easterly midlevel flow will persist on the southern periphery of an
upper high over the Four Corners. Steep midlevel lapse rates and
persistent moisture across the region will foster thunderstorm
development across the higher terrain during the evening. The hot
and well mixed boundary layer will support strong outflow gusts as
convection moves westward off higher terrain toward the lower
deserts.

..Leitman/Marsh.. 08/08/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Aug 8 12:45:18 2026

ACUS01 KWNS 081245
SWODY1
SPC AC 081243

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0743 AM CDT Sat Aug 08 2026

Valid 081300Z - 091200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHERN
PARTS OF THE MID-ATLANTIC INTO SOUTHERN PORTIONS OF THE NORTHEAST...

...SUMMARY...
Scattered strong to severe thunderstorms capable primarily of
damaging gusts will be possible today across the Mid-Atlantic states
into southern New England.

...Mid-Atlantic states into southern New England...
Satellite imagery this morning indicates a weak disturbance moving
east across the Lower Great Lakes, with early morning
showers/thunderstorms from WV/PA into western NY likely associated
with this feature. Strong heating from Chesapeake Bay northward
into southern portions of the Northeast will yield around 2000 J/kg
MLCAPE by early afternoon. Of particular note is seemingly adequate
strength of flow between 700-250 mb for organized line segments.
Given the relatively high PW environment (1.75-2.0 inches),
expecting a few clusters to evolve this afternoon with an attendant
risk for strong to locally severe gusts (50-65 mph). Have
expanded/increased severe-wind probabilities into southern New
England and southward into the Chesapeake Bay vicinity. Marginally
severe hail may also occur with the stronger cells before excessive
outflow leads to more linear structures as this activity pushes east
towards the coast by the early evening.

...Northern/Central Plains into MN/IA/MO...
Radar/satellite mosaic shows a cluster of strong to locally severe thunderstorms over the NE Sandhills this morning. This activity may
continue southeast this morning but weaken as it moves across
central NE. Above average uncertainty/low confidence for this
forecast is due in part to weak to negligible forcing features and
large model spread on potential evolution of isolated to widely
scattered storms later today into tonight. Nonetheless, a strongly
unstable airmass is forecast to develop by early afternoon across
much of the region with 60s to lower 70s boundary layer dewpoints
beneath steep 700-500 mb lapse rates.

Several areas of convection may develop during the late
afternoon/evening near the surface trough, and overnight near the southward-sagging surface front. Weak convergence along early day
outflow may rejuvenate convection or lead to additional isolated
storms over southern NE into northern KS. This may also coincide
with an increasing low-level jet across the central Plains during
the evening into the overnight, but capping will likely limit storm
coverage except perhaps near a southward-sagging surface front near
the ND/SD border and with warm advection over southern MN into IA.
Large hail and severe gusts will be possible with the more intense thunderstorms.

Additional high-based convection is possible across eastern CO and
western KS/NE. A hot and well mixed boundary layer will probably
support isolated severe gusts.

...AZ...
Easterly midlevel flow will persist on the southern periphery of an
upper high over the Four Corners. Steep midlevel lapse rates and
persistent moisture across the region will foster thunderstorm
development across the higher terrain during the evening. The hot
and well mixed boundary layer will support strong outflow gusts as
convection moves westward off higher terrain toward the lower
deserts.

..Smith/Kerr.. 08/08/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Aug 8 16:07:18 2026

ACUS01 KWNS 081607
SWODY1
SPC AC 081605

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1105 AM CDT Sat Aug 08 2026

Valid 081630Z - 091200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHERN
VIRGINIA INTO SOUTHEAST NEW YORK AND WESTERN MASSACHUSETTS....

...SUMMARY...
Scattered strong to severe thunderstorms capable primarily of
damaging gusts will be possible today from the Mid-Atlantic states
into southwest New England.

...Northeast States...
Morning water vapor imagery shows a low-amplitude shortwave trough
over OH tracking eastward. A warm/moist air mass is present ahead of
the trough, with pockets of MLCAPE over 2000 J/kg expected later
today. Large scale forcing associated with the trough is rather
weak, and overall coverage of storms may be rather isolated.
However, stronger winds aloft than yesterday suggest a conditional
risk of wind damage with any sustained storm later today. Have
extended the SLGT risk area a little farther north into NY/MA where
morning model guidance suggests higher coverage/confidence in
storms. Have also extended the MRGL farther west into OH beneath
the upper trough where widely scattered storms may also produce
gusty/damaging winds.

...Western NC...
A few afternoon thunderstorms are expected to form off the mountains
of western NC and vicinity, and track slowly southeastward. Strong
daytime heating, humid conditions, and sufficient CAPE may promote a
risk of gusty/damaging winds in the strongest cores.

...North TX...
Isolated thunderstorms are expected to form along an E-W axis across
north TX this afternoon in a hot/humid air mass. The strongest of
these slow-moving cells may produce damaging winds.

...NE/KS...
A cluster of strong thunderstorms is ongoing over central NE. This
activity may persist into the afternoon, tracking southeastward
toward northeast KS/northwest MO. Given the corridor of high CAPE
in this zone, a few strong/severe storms capable of damaging winds
and hail are possible.

...ND/SD/MN/IA...
A strengthening southerly low-level jet will likely lead to
scattered thunderstorms tonight after midnight over central ND.
These storms are expected to develop southeastward into parts of
SD/MN/IA before 12z. Relatively strong vertical shear will support
supercells capable of hail and damaging winds.

...AZ...
Full sunshine and sufficient CAPE will once again promote
thunderstorm develop off the Mogollon Rim this afternoon and
evening. Forecast soundings show increasing mid-level moisture
through the evening as an upper trough passes to the south, perhaps
aiding convective maintenance westward into the lower elevations.
If so, given the favorable steering flow, strong/severe outflow
winds could spread into the PHX area around 00z. This scenario will
be monitored for a possible upgrade to SLGT in later outlooks.

..Hart/Weinman.. 08/08/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Aug 8 19:20:50 2026

ACUS01 KWNS 081920
SWODY1
SPC AC 081919

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0219 PM CDT Sat Aug 08 2026

Valid 082000Z - 091200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS NORTHERN VIRGINIA
INTO SOUTHEAST NEW YORK AND WESTERN MASSACHUSETTS...

...SUMMARY...
Scattered strong to severe thunderstorms capable primarily of
damaging gusts will be possible today from the Mid-Atlantic states
into southwest New England. Isolated instances of large to very
large hail will be possible across the northern Plains.

...20z Update...
Adjustments were made to remove the Slight/Marginal risks across
portions of the Northeast behind ongoing convection. Widely
scattered thunderstorms capable of damaging wind will continue in
the remaining risk area though the afternoon.

In the northern Plains/Midwest, a conditional risk for significant
hail was added with this update across portions of the Dakotas into
western Minnesota. As thunderstorms develop late this evening near
the nose of the nocturnal low-level jet, forecast soundings suggest
that moderate to strong cape and steep low to mid-level lapse rates
will be in place amid strong deep layer shear profiles. This will
support potential for a few initial supercells capable of large to
very large hail (some 2+ inches in diameter). This threat should
remain isolated enough to preclude higher outlook probabilities.

See previous discussion below for more information.

..Thornton.. 08/08/2026

.PREV DISCUSSION... /ISSUED 1105 AM CDT Sat Aug 08 2026/

...Northeast States...
Morning water vapor imagery shows a low-amplitude shortwave trough
over OH tracking eastward. A warm/moist air mass is present ahead of
the trough, with pockets of MLCAPE over 2000 J/kg expected later
today. Large scale forcing associated with the trough is rather
weak, and overall coverage of storms may be rather isolated.
However, stronger winds aloft than yesterday suggest a conditional
risk of wind damage with any sustained storm later today. Have
extended the SLGT risk area a little farther north into NY/MA where
morning model guidance suggests higher coverage/confidence in
storms. Have also extended the MRGL farther west into OH beneath
the upper trough where widely scattered storms may also produce
gusty/damaging winds.

...Western NC...
A few afternoon thunderstorms are expected to form off the mountains
of western NC and vicinity, and track slowly southeastward. Strong
daytime heating, humid conditions, and sufficient CAPE may promote a
risk of gusty/damaging winds in the strongest cores.

...North TX...
Isolated thunderstorms are expected to form along an E-W axis across
north TX this afternoon in a hot/humid air mass. The strongest of
these slow-moving cells may produce damaging winds.

...NE/KS...
A cluster of strong thunderstorms is ongoing over central NE. This
activity may persist into the afternoon, tracking southeastward
toward northeast KS/northwest MO. Given the corridor of high CAPE
in this zone, a few strong/severe storms capable of damaging winds
and hail are possible.

...ND/SD/MN/IA...
A strengthening southerly low-level jet will likely lead to
scattered thunderstorms tonight after midnight over central ND.
These storms are expected to develop southeastward into parts of
SD/MN/IA before 12z. Relatively strong vertical shear will support
supercells capable of hail and damaging winds.

...AZ...
Full sunshine and sufficient CAPE will once again promote
thunderstorm develop off the Mogollon Rim this afternoon and
evening. Forecast soundings show increasing mid-level moisture
through the evening as an upper trough passes to the south, perhaps
aiding convective maintenance westward into the lower elevations.
If so, given the favorable steering flow, strong/severe outflow
winds could spread into the PHX area around 00z. This scenario will
be monitored for a possible upgrade to SLGT in later outlooks.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Aug 9 00:44:18 2026

ACUS01 KWNS 090044
SWODY1
SPC AC 090042

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0742 PM CDT Sat Aug 08 2026

Valid 090100Z - 091200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE NORTHERN/CENTRAL PLAINS INTO MN/IA...OVER CENTRAL/SOUTHERN
AZ...AND FROM CENTRAL OH INTO WESTERN NY...

...SUMMARY...
Isolated instances of large to very large hail will be possible
across the northern Plains through tonight.

...Dakotas into MN/IA and the MO Valley...

Isolated thunderstorms have developed early this evening across
south-central ND. Isolated large to very large hail may accompany
these storms if they can intensify and be maintained. It is
uncertain if this convection will continue to develop east/southeast
into SD given strong capping, or if additional convection will
develop later tonight as a low-level jet increases. Reference MCD
1872 for more short term information. Despite uncertainty in
convective evolution through the evening into tonight, severe
potential, mainly in the form of large hail near 2 inch diameter,
and strong wind gusts, remains possible.

...Ohio Valley into western NY...

Thunderstorm clusters have develop ahead of a surface front from OH
into western PA/NY. This activity will continue to spread eastward
within moderate instability through early tonight. Sporadic strong
wind gusts will be possible for a few more hours before weakening
with loss of daytime heating and increasing nocturnal boundary layer stabilization.

...AZ...

Isolated thunderstorms developing over higher terrain will continue
to spread westward across the lower deserts tonight. Strong wind
gusts will be possible with this activity.

...CO/KS vicinity...

Thick smoke across the region has muted instability across CO into
northeast KS and vicinity. Any stronger convection has moved south
into southwest KS where locally gusty winds are possible for another
couple of hours. However, severe potential appears limited with
anemic high-based showers moving across eastern CO into northwest KS
and southwest NE. As such, severe probabilities have been removed.

...TX...

Outflow from a thunderstorm cluster across northeast TX will
continue to progress south/southwest this evening. Instability
lessens with westward extent and, with loss of daytime heating,
low-level inhibition will increase. Severe potential has largely
diminished and probabilities have been removed.

...NC vicinity...

Thunderstorms have gradually weakened over the past 30-60 minutes as
low-level inhibition increases with the loss of daytime heating. As
such, severe potential has diminished and severe probabilities have
been removed.

..Leitman.. 08/09/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Aug 9 05:17:52 2026

ACUS01 KWNS 090517
SWODY1
SPC AC 090515

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1215 AM CDT Sun Aug 09 2026

Valid 091200Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MIDWEST...AND PORTIONS OF THE DAKOTAS...

...SUMMARY...
Scattered damaging winds may occur today into this evening from
southern Minnesota and eastern Iowa eastward across parts of
northern Illinois, southern Wisconsin, southern Lower Michigan,
northwest Ohio, and northern Indiana. Damaging wind and hail is also
expected across portions of the Dakotas.

...IA/MN into the Midwest...

Convection is expected to be ongoing this morning across parts of
southern MN into eastern IA. This early day activity could pose a
risk for damaging gusts. This activity is likely to continue to
spread eastward across the Lake Michigan vicinity through the
afternoon on the nose a of modest low-level jet and along a surface
front oriented across southern WI and Lower MI. This activity could
intensify as is moves into a destabilizing airmass by midday.

Additional development is possible within the moisture rich warm
sector across northern IL/IN along the southern flank of ongoing
convection and/or outflow. Strong to extreme instability is
forecast, while vertically veering wind profiles support 30+ kt
effective shear magnitudes. Low-level SRH also will be enhanced
along the surface boundary. While damaging winds are expected to be
the primary hazard with convection, some risk for hail and a tornado
or two also will exist through evening. Depending on the evolution
of morning convection, it is possible higher probabilities will be
needed in subsequent outlooks.

...Dakotas and western NE...

A surface front is expected to develop southward across the central
Plains, becoming oriented across northern KS by tonight. Low-level
warm advection atop the boundary, and surface winds becoming south/southeasterly with time will maintain 60s dewpoints across the
region. Within this post-frontal upslope regime, moderate
northwesterly flow aloft will persist. A modest south/southwesterly
low-level jet is also forecast to develop during the evening hours.
Low-level convergence within the warm advection regime and
increasing low-level jet may be sufficient for isolated to scattered thunderstorm development. Supercell wind profiles and steep
low-level lapse rates will support initial storms capable of large
hail and damaging winds. If sufficient clusters/outflow
consolidation can occur, upscale growth during the late evening into
overnight hours is possible, with an increasing risk for swaths of severe/damaging gusts.

...Southern Appalachians...

Scattered thunderstorm development is expected over higher terrain
within a seasonally moist and unstable airmass. Steepening low-level
lapse rates and high PW values may support locally strong gusts with
wet microbursts through early evening.

...AZ...

Modest easterly mid/upper flow will persist across the region on the
southern periphery of an upper high over the Four Corners. Another
day of hot conditions will promote steep lapse rates and modest destabilization. As convection develops over higher terrain and
spread westward, strong outflow gusts may occur.

..Leitman/Moore.. 08/09/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Aug 9 12:40:58 2026

ACUS01 KWNS 091239
SWODY1
SPC AC 091237

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0737 AM CDT Sun Aug 09 2026

Valid 091300Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE MIDWEST...

...SUMMARY...
Scattered damaging winds may occur today into this evening from
southern Minnesota and eastern Iowa eastward across parts of
northern Illinois, southern Wisconsin, southern Lower Michigan,
northwest Ohio, and northern Indiana. Damaging wind and hail are
also expected across portions of the Dakotas.

...Midwest...
Radar/satellite composite shows a corridor of showers/thunderstorms
from northern MO into southern MN and western WI associated with
isentropic lift on the nose of a 40-kt southwesterly LLJ. A
localized risk for hail/wind may accompany this activity this
morning as it shifts eastward across the MS River towards Lake MI
through midday. Considerable uncertainty remains regarding the
severe forecast for the eastern IA into the southern Great Lakes
portion of the Slight Risk. Showers/thunderstorms and related
convective debris/outflow will be influential on airmass recovery
later this afternoon. It seems plausible a warm front draped over
the Corn Belt this morning will slowly advance northward into the
southwest Great Lakes with an increasingly unstable airmass
developing to the south/west of this convectively augmented
baroclinic zone.

Model forecast soundings show ample CAPE aided by the northern rim
of lower to mid 70s F surface dewpoints into northern portions of
IL/IN. Adequately strong and vertically veering wind profiles will
support 30-40 kt effective shear magnitudes. Low-level SRH may also
be locally boosted in the vicinity of the warm front/effective
boundary, which could then play a role in severe potential if a
supercell or linear segments were to develop and favorably interact
within this corridor. Rather poor depiction of this morning's
thunderstorm evolution (i.e., 00z HREF members) casts large
uncertainty where a couple of more intense thunderstorm clusters
will ultimately develop. It seems the greatest potential for severe
will be centered over northern IL later this afternoon through the
evening, but confidence remains low regarding details and the need
for spatial refinements of the severe risk area and the need for
potential higher probabilities.

...Dakotas and western NE...
A surface front is expected to push southward across the central
Plains, becoming oriented across northern KS by tonight. Low-level
warm advection atop the boundary, and surface winds becoming south/southeasterly with time will maintain 60s dewpoints across the
region. Within this post-frontal upslope regime, a reservoir of
mainly 60s F dewpoints will reside beneath moderate northwesterly
flow aloft. Supercell wind profiles and steep low-level lapse rates
will support initial storms capable of large hail and severe gusts,
especially as this activity over the western Dakotas moves
southeastward into richer moisture. A small cluster may eventually
evolve during the overnight with an attendant risk for severe gusts
and perhaps large hail.

...Southern Appalachians...
Scattered thunderstorm development is expected over higher terrain
within a seasonally moist and unstable airmass. Steepening
low-level lapse rates and high PW values may support locally strong
gusts with wet microbursts through early evening.

...AZ...
Modest easterly mid/upper flow will persist across the region on the
southern periphery of an upper high over the Four Corners. Another
day of hot conditions will promote steep lapse rates and modest destabilization. As convection develops over higher terrain and
spread westward, strong outflow gusts may occur.

..Smith/Kerr.. 08/09/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Aug 9 15:58:22 2026

ACUS01 KWNS 091558
SWODY1
SPC AC 091556

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1056 AM CDT Sun Aug 09 2026

Valid 091630Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
OVER PARTS OF THE MIDWEST...AND TONIGHT OVER PARTS OF THE
DAKOTAS....

...SUMMARY...
Scattered damaging winds are possible today into this evening from
southern Wisconsin eastward across parts of northern Illinois,
southern Lower Michigan, northwest Ohio, and northern Indiana.
Damaging wind and hail may also occur across portions of the Dakotas
tonight.

...Midwest...
A persistent cluster of thunderstorms over southern WI appears
likely to continue southeastward through much of the day into parts
of IL/MI/IN and eventually OH. This activity will track near a
NW-SE oriented baroclinic zone, with dewpoints in the lower 70s to
the south. Eventually, low-level lapse rates will become
sufficiently steep to support damaging wind gusts along the leading
edge of the storms. Later tonight, strengthening southwesterly
low-level winds will enhance warm advection and lift over parts of
IL/IN, potentially leading to another round of strong/severe storms
capable of damaging winds and hail after 06z.

...Dakotas...
12z model guidance continues to decrease the confidence in overnight
severe storms, with some CAM solutions showing no thunderstorms.
Therefore have made the SLGT area smaller and focused where there is
highest confidence in isolated storms. Forecast soundings continue
to indicate steep mid-level lapse rates and strong deep shear,
providing a conditional risk of supercells if convection can be
sustained.

...AZ...
Thunderstorms are once again predicted to form along the Rim and
track westward toward the PHX metro area this evening. The strength
of the steering flow, instability, and mid-level moisture all appear
favorable for a severe risk. However, mesoscale details of the
evolution of the storms over high terrain will dictate the eventual
risk.

..Hart/Weinman.. 08/09/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Aug 9 20:00:58 2026

ACUS01 KWNS 092000
SWODY1
SPC AC 091959

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0259 PM CDT Sun Aug 09 2026

Valid 092000Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE MIDWEST INTO THE OHIO VALLEY...

...SUMMARY...
Scattered damaging winds are possible today into this evening from
southern Wisconsin eastward across parts of northern Illinois,
southern Lower Michigan, northwest Ohio, and northern Indiana.
Damaging wind and hail may also occur across portions of the Dakotas
tonight.

...20Z Update...
The main changes made to the outlook were to remove the Slight Risk
and more broadly expand Marginal Risk severe probabilities across
the central/northern Plains. CAM guidance has shown appreciable
uncertainty regarding storm coverage in this region, and trends in
model output continue to show sparse coverage. Nonetheless,
widespread 2000+ J/kg MLCAPE amid 50+ kts of effective bulk shear
may support a couple of severe multicells or supercells should any
storms manage to become sustained this afternoon or evening. The
Slight Risk along/south of the Great Lakes was expanded slightly
eastward into northern OH to account for some boundary layer
destabilization ahead of an approaching MCS, where a few damaging
gusts are possible.

Otherwise, the previous forecast remains on track, with only minor
changes made to the severe/thunder probabilities to account for the
latest observations and guidance consensus.

..Squitieri.. 08/09/2026

.PREV DISCUSSION... /ISSUED 1056 AM CDT Sun Aug 09 2026/

...Midwest...
A persistent cluster of thunderstorms over southern WI appears
likely to continue southeastward through much of the day into parts
of IL/MI/IN and eventually OH. This activity will track near a
NW-SE oriented baroclinic zone, with dewpoints in the lower 70s to
the south. Eventually, low-level lapse rates will become
sufficiently steep to support damaging wind gusts along the leading
edge of the storms. Later tonight, strengthening southwesterly
low-level winds will enhance warm advection and lift over parts of
IL/IN, potentially leading to another round of strong/severe storms
capable of damaging winds and hail after 06z.

...Dakotas...
12z model guidance continues to decrease the confidence in overnight
severe storms, with some CAM solutions showing no thunderstorms.
Therefore have made the SLGT area smaller and focused where there is
highest confidence in isolated storms. Forecast soundings continue
to indicate steep mid-level lapse rates and strong deep shear,
providing a conditional risk of supercells if convection can be
sustained.

...AZ...
Thunderstorms are once again predicted to form along the Rim and
track westward toward the PHX metro area this evening. The strength
of the steering flow, instability, and mid-level moisture all appear
favorable for a severe risk. However, mesoscale details of the
evolution of the storms over high terrain will dictate the eventual
risk.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Aug 10 00:42:58 2026

ACUS01 KWNS 100042
SWODY1
SPC AC 100041

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0741 PM CDT Sun Aug 09 2026

Valid 100100Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE MIDWEST...

...SUMMARY...
Severe storms are possible this evening into the overnight hours
across portions of the Midwest. Damaging winds will be the main
hazard with this activity. Additional strong to severe storms may
occur from western Nebraska into the Dakotas, and across Arizona.

...Midwest...

A bowing line of storms will continue to move east/southeast across
northern OH the next few hours. Occasional damaging gusts will be
possible with this activity before weakening after 04z as
instability wanes across northeast OH/western PA.

Model guidance continues to indicated additional convection will
develop across portions of eastern IA/northern IL this evening. This
activity may develop along residual outflow and a southward sagging
surface front as a low-level jet increases over the next few hours. Thunderstorm clusters may grow into one or more MCSs moving east
across northern IL into IN and perhaps southern Lower MI.

...Northern/Central Plains...

Damaging wind and hail will be possible with convection moving
across western NE this evening. As ongoing storms track
east/southeast, they will encounter richer low-level moisture and
increasing instability. While stronger capping persisted with
eastward extent, even elevated storms will pose a severe risk as
they track across WW 0549.

Severe potential is less certain with northward extent across the
Dakotas. Low-level moisture will increase during the evening and
overnight hours, but currently, instability remains weak and capping
is strong. Isolated strong cells over northeast MT will continue to
develop southeast into limited instability but stronger vertical
shear. If storms can be maintained and additional development occurs
later this evening/overnight isolated hail and strong wind gusts
will be possible.

...AZ...

Similar to previous days, easterly midlevel flow will support
convection moving westward off higher terrain and across the lower
deserts within weak to moderate instability and steep low-level
lapse rates. Strong to severe gusts will be possible with this
activity.

..Leitman.. 08/10/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Aug 10 05:27:02 2026

ACUS01 KWNS 100526
SWODY1
SPC AC 100525

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1225 AM CDT Mon Aug 10 2026

Valid 101200Z - 111200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTION OF
THE MIDWEST INTO PA AND NORTHERN MD/VA...AND ACROSS PARTS OF THE
NORTHERN PLAINS...

...SUMMARY...
Thunderstorms with severe wind gusts will be possible this afternoon
and evening from northern Illinois eastward into Pennsylvania.
Severe gusts and hail will also be possible from parts of the
central and northern Plains into the Midwest, with scattered strong
storms over southern Arizona.

...Synopsis...

A belt of enhanced west/northwesterly flow aloft will overspread the
northern Plains to the Midwest and southern New England
today/tonight. Only modest height falls are forecast at best.
However, several convectively enhanced vorticity maxima are forecast
to migrate through this upper flow regime, focusing several areas of
severe storm potential today into tonight from the northern Plains
to the upper Ohio Valley and parts of the Mid-Atlantic.

...IL to the Mid-Atlantic...

Early day thunderstorms may move across parts of the Midwest this
morning, but should generally be sub-severe. By midday, convection
could intensify within a couple of corridors. The first being the
upper Ohio Valley/PA/western NY. Thunderstorm clusters will pose a
risk for damaging winds and hail within a moderately unstable
airmass as convection spreads east toward the Mid-Atlantic.

Additional thunderstorm development is expected later in the
afternoon associated with another shortwave impulse spreading east
from IL into IN/OH. This activity will develop within strong
instability and rich boundary layer moisture. Modestly steep
midlevel lapse rates and effective shear greater than 40 kt will
support initial supercells. With time, sufficient clustering is
expected and bowing segments will be possible. Damaging wind and
hail will be the primary hazards, though a tornado or two also could
occur.

...Dakotas into Iowa...

Southeasterly low-level flow will transport mid/upper 60s dewpoints
north and west across SD, with 70s dewpoints common with southeast
extent across NE/IA/southern MN. This will support a corridor of
strong to extreme instability across the region. While coverage
remains uncertain, most guidance develops at least isolated
thunderstorms by evening. Elongated hodographs amid favorable deep
shear will support supercells and bows capable of large hail and
damaging winds. With time, it is possible sufficient clustering
occurs and upscale growth into a bowing MCS is possible as a
low-level jet develops overnight. If this occurs, a swath of
damaging winds is possible across parts of SD into northwest IA,
oriented along the stronger instability gradient.

...NE/CO/KS...

Scattered thunderstorms are expected to develop near a surface
trough across western NE/northeast CO by late afternoon/early
evening. This activity will spread east/southeast. Steep low-level
lapse rates will support strong outflow gusts and perhaps hail with
this activity.

...AZ...

Mid/upper easterly flow will persist today amid plentiful moisture
and strong heating. This will support thunderstorm development once
again across higher terrain. As storms propagate westward off the
higher terrain, isolated severe gusts will be possible.

..Leitman/Moore.. 08/10/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Aug 10 12:48:32 2026

ACUS01 KWNS 101248
SWODY1
SPC AC 101247

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0747 AM CDT Mon Aug 10 2026

Valid 101300Z - 111200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN
GREAT LAKES INTO THE MID-ATLANTIC STATES...PORTIONS OF THE UPPER
MIDWEST AND CENTRAL HIGH PLAINS...AND SOUTHERN ARIZONA...

...SUMMARY...
Thunderstorms with severe wind gusts will be possible this afternoon
and evening from northern Illinois eastward into Pennsylvania.
Severe gusts and hail will also be possible from parts of the
central and northern Plains into the Midwest, with scattered severe
storms over southern Arizona.

...Synopsis...
Another highly uncertain and complex forecast with mesoscale
convective dependencies apparent this forecast update. Water-vapor
imagery implies a belt of west-northwest mid to high-level flow
extending across the northern High Plains east through much of the
Midwest, and to the north of a flattened mid-level ridge extending
from the Four Corners to FL. Embedded within the flow, a
convectively augmented disturbance over the southern Great Lakes
will move east into PA by early this afternoon. Another minor
perturbation over southwest MT this morning will quickly move into
the Dakotas by early evening and probably influence the severe
threat from SD into adjacent parts of IA/MN overnight.

...IL to the Mid-Atlantic...
Radar mosaic this morning shows an organized line segment moving
east along the OH-Lake Erie shoreline and a couple of other
thunderstorm clusters over western OH and south-central PA. The
Detroit, MI WSR-88D VAD showed a mid-level speed max associated with
the convectively augmented vorticity max moving east across the Lake
Erie vicinity. Gradual intensification of storms is expected this
morning as the boundary layer heats downstream across OH into PA and
the Mid-Atlantic states (refer to MCD 1892 for short-term details
regarding the northeast OH thunderstorms). Of particular note, the
12 UTC Pittsburgh, PA and Wilmington, OH raobs showed a moderate to
very unstable airmass (1800-2700 J/kg MLCAPE, respectively) in place
over the upper OH Valley. Severe gusts capable of scattered wind
damage will be possible through the afternoon with any stronger
thunderstorms and clusters of storms. Farther west, models show
storm redevelopment perhaps centered over northern IN/IL later this afternoon/evening. Shear/buoyancy profiles will support organized
storms, including supercells and linear clusters. Damaging wind and
hail will be the primary hazards, though a tornado or two also could
occur.

...Dakotas into MN/IA...
Similar to previous forecast thinking, southeasterly low-level flow
will aid in the transport of seasonably rich moisture (mainly 60s F
surface dewpoints) north and west into SD. Model forecast soundings
show large buoyancy developing by mid afternoon within the
aforementioned moist plume. The weak impulse implied by model
guidance moving into western SD may enable at least isolated to
potentially scattered storms developing towards early evening over
western and central SD. The 00z ECMWF and 00z HREF consensus
suggest a linear cluster evolves during the evening and grows
upscale into an MCS during the overnight moving east-southeast along
a residual frontal zone. Have included an intensity level-1 to
denote this conditional but significant wind risk if this forecast
scenario occurs.

...AZ...
Mid/upper easterly flow will persist today amid plentiful moisture
and strong heating. This will support thunderstorm development once
again across higher terrain. Scattered storms are forecast to
eventually develop with their cold pools coalescing over the lower
desert. Based on the latest CAM guidance and inverted-V profiles
with marginally supportive shear for loose storm organization, have
upgraded a part of the lower desert into higher severe-wind
probabilities. Widely scattered to scattered severe gusts 60-75 mph
are possible with this activity.

...NE/CO/KS...
Scattered thunderstorms are expected to develop near a surface
trough across western NE/northeast CO by late afternoon/early
evening. As the high-based storms mature into possibly a small
linear cluster and move into richer moisture with east extent, steep
low- to mid-level lapse rates will support severe gusts (60-75 mph)
and perhaps hail with this activity.

..Smith/Kerr.. 08/10/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Aug 10 16:02:34 2026

ACUS01 KWNS 101602
SWODY1
SPC AC 101600

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1100 AM CDT Mon Aug 10 2026

Valid 101630Z - 111200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF
ILLINOIS TO THE MID-ATLANTIC COAST...OVER PARTS OF THE NORTHERN AND
CENTRAL PLAINS...AND OVER SOUTHERN ARIZONA...

...SUMMARY...
Thunderstorms with severe wind gusts will be possible this afternoon
and evening from northern Illinois eastward into Pennsylvania.
Severe gusts and hail will also be possible from parts of the
central and northern Plains into the Midwest, with scattered severe
storms over southern Arizona.

...PA/NY/NJ...
Multiple clusters and lines of thunderstorms are ongoing this
morning from western PA. So far, this activity has produced limited
severe wind gusts due to weak low-level lapse rates. However,
continued heating over central/eastern PA will eventually allow the
storms to be more efficient wind-producers with locally damaging
gusts expected. See MD #1894 for further details.

...OH/WV...
A secondary cluster of storms over central OH is tracking
southeastward in a moderately sheared environment. Rapid heating is
occurring to the southwest of this cluster, which should result in intensification by mid afternoon. Storms will likely spread into
northern WV with a risk of damaging wind gusts and perhaps hail.

...SD/MN/IA...
A large reservoir of unstable air will reside across much of SD
today, with MLCAPE values over 3000 J/kg, steep lapse rates, and
dewpoints in the upper 60s. A capping inversion should preclude
sustained convection until after 00z when strengthening southerly
low-level flow and warm advection will aid initiation. Supercells
capable of large hail and damaging winds are expected, with eventual
upscale organization into a bowing MCS possible through the
evening/night.

...CO/KS...
Most model guidance shows the likelihood of scattered high-based
thunderstorm development late this afternoon over northeast CO,
spreading into northwest KS and southwest NE this evening. Cloud
cover is somewhat limiting heating, but sufficient CAPE and winds
aloft may promote a period of damaging wind potential later today.

...AZ...
Another round of evening thunderstorms is expected to initiate off
the higher terrain of east-central AZ and spread westward toward the
TUS/PHX metro areas. Parameters remain conditionally favorable for
damaging winds in any sustained/organized clusters of storms that
may develop.

..Hart/Weinman.. 08/10/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Aug 10 19:22:08 2026

ACUS01 KWNS 101921
SWODY1
SPC AC 101920

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0220 PM CDT Mon Aug 10 2026

Valid 102000Z - 111200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
CENTRAL AND EASTERN SOUTH DAKOTA INTO FAR SOUTHWESTERN MINNESOTA AND NORTHWESTERN IOWA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE CENTRAL HIGH PLAINS TO THE MID ATLANTIC...AND PARTS OF SOUTHERN
ARIZONA...

...SUMMARY...
Damaging gusts will continue with a cluster of storms progressing
across the Mid Atlantic area this afternoon. Several other severe
wind/hail producing storms remain possible across the Ohio Valley. A
severe wind swath, with a few 75+ mph gusts is possible across
portions of the northern Plains into the Midwest tonight. A few
severe gusts may also occur this evening over central and southern
Arizona.

...20Z Update...
The main change made to this outlook was to upgrade portions of SD
into MN and IA to a Category 3/Enhanced risk, driven by 30
percent/CIG1 probabilities. Confidence is increasing that robust supercell/multicellular development this evening will result in the
upscale growth of a cold-pool-driven MCS tonight. The best time for
the wind swath will be in the 03-09Z period. 8.5-9 C/km mid-level
lapse rates, and 40-50 kts of effective bulk shear (aligned normal
to forecast MCS orientation) will favor a swath of severe gusts from
at least central SD into northern IA tonight. There is some chance
that the wind swath may continue to the IA/IL/WI border by 12Z
Tuesday morning, hence the joining of the two Slight risk areas
along the MS River. Given such steep mid-level lapse rates, at least
a few 75+ mph gusts are possible, even if storms remain more
supercellular or multicellular. A few instances of 2+ inch diameter
hail may also occur with initial storms, and a tornado could develop
either with initial supercells, or line-embedded mesovortices should
a bow echo form. Severe wind/hail probabilities and CIG1 areas were
also expanded farther west across the central High Plains for the
possibility of a 2+ inch diameter hail instance or a 75+ mph gust
(given the aforementioned lapse rates/shear).

Additionally, 30 percent severe wind probabilities were expanded to
the East Coast ahead of an ongoing cold-pool-driven MCS, where
numerous wind damage reports continue to be received. Finally,
several other minor adjustments were made to the ongoing severe and
thunder probabilities to account for the latest observations and
guidance consensus.

..Squitieri.. 08/10/2026

.PREV DISCUSSION... /ISSUED 1100 AM CDT Mon Aug 10 2026/

...PA/NY/NJ...
Multiple clusters and lines of thunderstorms are ongoing this
morning from western PA. So far, this activity has produced limited
severe wind gusts due to weak low-level lapse rates. However,
continued heating over central/eastern PA will eventually allow the
storms to be more efficient wind-producers with locally damaging
gusts expected. See MD #1894 for further details.

...OH/WV...
A secondary cluster of storms over central OH is tracking
southeastward in a moderately sheared environment. Rapid heating is
occurring to the southwest of this cluster, which should result in intensification by mid afternoon. Storms will likely spread into
northern WV with a risk of damaging wind gusts and perhaps hail.

...SD/MN/IA...
A large reservoir of unstable air will reside across much of SD
today, with MLCAPE values over 3000 J/kg, steep lapse rates, and
dewpoints in the upper 60s. A capping inversion should preclude
sustained convection until after 00z when strengthening southerly
low-level flow and warm advection will aid initiation. Supercells
capable of large hail and damaging winds are expected, with eventual
upscale organization into a bowing MCS possible through the
evening/night.

...CO/KS...
Most model guidance shows the likelihood of scattered high-based
thunderstorm development late this afternoon over northeast CO,
spreading into northwest KS and southwest NE this evening. Cloud
cover is somewhat limiting heating, but sufficient CAPE and winds
aloft may promote a period of damaging wind potential later today.

...AZ...
Another round of evening thunderstorms is expected to initiate off
the higher terrain of east-central AZ and spread westward toward the
TUS/PHX metro areas. Parameters remain conditionally favorable for
damaging winds in any sustained/organized clusters of storms that
may develop.

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Aug 11 00:55:42 2026

ACUS01 KWNS 110055
SWODY1
SPC AC 110053

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0753 PM CDT Mon Aug 10 2026

Valid 110100Z - 111200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTH DAKOTA...SOUTHWEST MINNESOTA...AND NORTHWEST IOWA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE
NORTHERN/CENTRAL PLAINS TO THE OHIO VALLEY...AND ACROSS PART OF
AZ...

...SUMMARY...
A severe wind swath, with a few 75+ mph gusts is possible across
portions of the northern Plains into the Midwest tonight. A few
severe gusts may also occur over central and southern Arizona.

...South Dakota into Iowa vicinity...

A small cluster of storms near the western ND/SD border may be the
start of what is expected to be a severe MCS through the overnight
hours. These storms are developing within a corridor of strong
instability and favorable deep layer shear. The 00z ABR RAOB shows a
very favorable thermodynamic and kinematic parameter space for
initial supercells growing upscale into a bowing MCS as a low-level
jet increases tonight. This environment is characterized by an elongated/straight hodograph, steep lapse rates and strong
instability with a layer of drier air around 700 mb atop a very
moist boundary layer. This profile suggests sufficient cold pool
generation is possible, aiding in development of a forward
propagating bowing MCS capable of severe gusts (some 75+ mph)
tonight into early Tuesday. Initial supercells also may pose a risk
for large hail up to 2.5 inches. Reference MCD 1908 for more short
term details.

...Central High Plains...

Scattered strong to severe storms will continue to pose a risk of
damaging winds and hail for a few more hours this evening,
particularly across parts of western NE. With loss of daytime
heating, this activity is expected to gradually wane in intensity.
Reference MCD 1910 for more short term information.

...AZ...

Widely scattered thunderstorms moving westward off higher terrain
will pose a risk for severe wind gusts over the next few hours.

...Northern IL into the Ohio Valley...

Convection ongoing across northern IN will persist into the evening
hours as it track east/southeast into OH. This activity may persist
through the overnight hours moving across much of the Ohio Valley
toward western PA and WV. Damaging winds will remain the primary
hazard, but isolated large hail may also occur.

...Mid-Atlantic/Northeast...

Strong wind gusts will remain possible with storms along the
southern Mid-Atlantic coast until they push completely offshore over
the next hour. Otherwise, severe potential has largely diminished
along the I-95 corridor and vicinity and severe probabilities have
been trimmed and/or removed. The exception will be across parts of
the northern NY into VT/NH area where a band of strong/severe storms
is ongoing along a surface boundary. Damaging gusts may continue
with this activity for a few more hours. Reference MCD 1909 for more
details.

..Leitman.. 08/11/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Aug 11 05:02:20 2026

ACUS01 KWNS 110502
SWODY1
SPC AC 110500

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1200 AM CDT Tue Aug 11 2026

Valid 111200Z - 121200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM NORTHERN
ILLINOIS INTO THE OHIO VALLEY...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
NORTHERN PLAINS...AND FROM IOWA TO VIRGINIA...

...SUMMARY...
Severe thunderstorms with damaging wind gusts will be possible today
from the eastern Iowa/northern Illinois vicinity into parts of the
Ohio Valley and central Appalachians. Areas of severe wind gusts and
hail will also be possible over parts of the northern Plains.

...IA to the Mid-Atlantic...

A complex forecast scenario is expected today from IA into the Ohio
Valley and adjacent Appalachia. More than one MCS may be ongoing at
the beginning of the period. The first across IA/southern MN, and
one further southeast across parts of the Midwest (exact location is
uncertain, but most likely IN/OH). Possible early day convection
across IN/OH will spread east/southeast across the Ohio Valley
during the morning posing risk for strong gusts. This activity is
likely to emerge across Appalachia, and eventually VA and the
broader Mid-Atlantic during the afternoon/evening. How much
destabilization will occur across VA and the Mid-Atlantic remains
uncertain given prior convection the previous day and potential
convective debris across the region. Some damaging wind potential
could materialize if sufficient destabilization occurs during the
afternoon.

The anticipated MCS over IA/southern MN early in the forecast period
is then expected to continue east/southeast across the Midwest,
fueled by a very moist and strongly unstable boundary layer.
Midlevel flow is forecast to be quite strong (by August standards),
with forecast guidance suggesting 700 mb greater than 60 kt
spreading across the Midwest through evening. While the exact
evolution of a potential severe MCS moving across the Midwest is
uncertain, it is possible the morning activity over IA will develop
southeast along outflow across the Ohio Valley. Given the strong
kinematic field and ample instability, if a well organized MCS is
maintained from IA southeast into the OH Valley, a swath of damaging
gusts (some 75+ mph) will be possible.

...Northern Plains...

East/southeasterly flow along the surface trough is forecast to
maintain 60s F dewpoints across the western Dakotas and parts of NE
this afternoon. Steep midlevel lapse rates atop the relatively moist
boundary layer, and strong heating will support a corridor of
moderate to strong instability across the western Dakotas. Scattered
storms are expected by early evening amid supercell wind profiles.
Elongated hodographs favorable for splitting cells with an
accompanying risk for large to very large hail are forecast.
Isolated severe gusts also could occur. Given a lack of stronger
low-level jet during the nighttime hours, it appears unlikely that
upscale growth will occur, and convection is expected to wane with
eastward extent overnight.

..Leitman/Moore.. 08/11/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Aug 11 12:28:46 2026

ACUS01 KWNS 111228
SWODY1
SPC AC 111226

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0726 AM CDT Tue Aug 11 2026

Valid 111300Z - 121200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTHERN
ILLINOIS INTO THE OHIO VALLEY...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
NORTHERN PLAINS...AND FROM EASTERN IOWA TO VIRGINIA AND NORTH
CAROLINA...

...SUMMARY...
Severe thunderstorms with damaging wind gusts will be possible today
from the eastern Iowa/northern Illinois vicinity into parts of the
Ohio Valley and central Appalachians. Areas of severe wind gusts
and hail will also be possible over parts of the northern Plains.

...IA to the Mid-Atlantic and Southeast...
An uncertain and inherently complex forecast is apparent this
morning from IA east-southeastward into the central Appalachians.
An impulse embedded within west-northwest flow and an overnight MCV
moving into IA from NE appear to be aiding in MCS development this
morning over eastern IA, with this thunderstorm complex moving into
northern IL through the late morning.

While the exact evolution of a potential severe MCS moving across
the Midwest is uncertain, a possible scenario is the thunderstorm
activity over IA either merges with additional storms developing
ahead of it or it continues to intensify into the main severe-wind
producing MCS. Another severe cluster is located over eastern IN
within the eastern envelope of the EML. Considered higher wind
probabilities to be delineated this outlook update, but it remains
unclear regarding sequential details that would lead to a
high-confidence mesoscale corridor of severe wind and associated
wind damage. Nonetheless, environmental parameters (e.g., very rich
moisture, steep 700-500 mb lapse rates, adequate deep-layer shear)
will strongly favor the development of mature/severe linear
clusters/bows with the more intense storms that eventually evolve
today. This activity will likely move along a large CAPE gradient
that will likely be reinforced by early morning convection.
Scattered severe gusts (60-85 mph) will be likely in the favored
mesoscale corridors with swaths of concentrated wind damage. A
lower but appreciable severe risk may extend into VA and NC with a
lower severe threat with south extent into SC/GA.

...Northern Plains...
East/southeasterly flow along the surface trough is forecast to
maintain 60s F dewpoints across the western Dakotas and parts of NE
this afternoon. Steep midlevel lapse rates atop the relatively
moist boundary layer, and strong heating will support a corridor of
moderate to strong instability across the western Dakotas.
Scattered storms are expected by early evening amid supercell wind
profiles. Elongated hodographs favorable for splitting cells with
an accompanying risk for large to very large hail are forecast.
Isolated severe gusts also could occur. Given the lack of a
stronger low-level jet during the nighttime hours, it appears
unlikely that upscale growth will occur, and convection is expected
to wane with eastward extent overnight.

...Mojave Desert of CA...
Early morning radar imagery shows an MCV moving slowly northwest
over the lower CO River Valley and this feature is likely associated
with a weak disturbance moving northwest into southern CA. The
airmass across the desert will undergo strong heating in wake of
early day cloud debris. Another likely convectively augmented
mid-level impulse will move across southern AZ towards southern CA
today. Widely scattered thunderstorms are forecast to develop this
afternoon amid a seasonably moist airmass and an inverted-V
thermodynamic profile is depicted in forecast soundings. Isolated
severe gusts are possible with the more intense downdrafts.

..Smith/Kerr.. 08/11/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Aug 11 16:13:24 2026

ACUS01 KWNS 111613
SWODY1
SPC AC 111611

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1111 AM CDT Tue Aug 11 2026

Valid 111630Z - 121200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
INTO EARLY TONIGHT FROM EASTERN ILLINOIS ACROSS PARTS OF THE OHIO
VALLEY...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
NORTHERN PLAINS...AND FROM EASTERN ILLINOIS TO VIRGINIA AND NORTH
CAROLINA...

...SUMMARY...
Severe thunderstorms with damaging wind gusts will occur today from
the northern Indiana into parts of the Ohio Valley and central
Appalachians. Areas of severe wind gusts and hail will also be
possible over parts of the northern Plains.

...IL/IN/OH...
A fast moving and intense bowing MCS is affecting the Chicago metro
area this morning with significant severe wind gusts. This activity
will race east-southeastward across northern IN and eventually
western OH. Increasingly widespread thunderstorms and associated
outflow ahead of this complex lends uncertainty to the evolution of
the bow, and the corridor of greatest damaging wind potential.
Refer to MDs #1921 and #1922 for further details.

...OH/WV/KY/VA...
Another linear MCS is affecting southeast OH, and will spread across
WV and into VA later today. The air mass ahead of this complex is
not as unstable, and considerable uncertainty exists regarding this
system's longevity. Nevertheless, sufficient flow aloft and
mesoscale organization will maintain a risk of damaging wind gusts.
Refer to MD #1923 for further details.

...ND/SD/NE...
Moderately strong westerly flow aloft is present today across the
Dakotas, with a moist and unstable air mass in place over the Black
Hills region. This will likely lead to widely scattered
thunderstorm development by early evening. Supercells capable of
large hail and damaging winds are expected. It is unclear how far
southeast these storms will maintain intensity, but model guidance
suggests at least into central SD before weakening overnight.

..Hart/Weinman.. 08/11/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Aug 11 20:01:54 2026

ACUS01 KWNS 112001
SWODY1
SPC AC 112000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Tue Aug 11 2026

Valid 112000Z - 121200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
INTO EARLY TONIGHT ACROSS PARTS OF THE MIDDLE OHIO VALLEY...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
NORTHERN PLAINS...AND FROM EASTERN ILLINOIS TO VIRGINIA AND NORTH
CAROLINA...

...SUMMARY...
Severe thunderstorms with damaging wind gusts will continue today
across parts of the Ohio Valley and central Appalachians. Large hail
and severe wind gusts are also forecast over parts of the northern
Plains.

...20Z Update...
The primary change with this update was trimming higher severe
probabilities in the wake of earlier convection that moved through
parts of eastern IL, northern IN, and northwestern OH. With that
said, a risk of severe wind gusts and hail will persist through some
of this corridor -- within a relatively narrow zone of
moderate-strong surface-based buoyancy along the southern edge of outflow-modified air. Refer to Severe Thunderstorm Watch 565 and MCD
1930 for more information.

Farther east, a well-established MCS is tracking southeastward
across southern OH toward northern KY. Over the next few hours,
these storms will continue to pose the greatest risk for a swath of
damaging wind gusts (some upwards of 75 mph) as they track
southeastward along a gradient of strong surface-based buoyancy amid
40 kt of deep-layer shear oriented perpendicular to the
well-established gust front. Additionally, a modest enhancement to
the low-level shear along the buoyancy gradient/baroclinic zone will
continue to support brief mesovortex tornadoes in the near-term. See
MCD 1931 for more information.

Elsewhere, the previous forecast remains on track and only minor
changes were made to the outlook.

..Weinman.. 08/11/2026

.PREV DISCUSSION... /ISSUED 1111 AM CDT Tue Aug 11 2026/

...IL/IN/OH...
A fast moving and intense bowing MCS is affecting the Chicago metro
area this morning with significant severe wind gusts. This activity
will race east-southeastward across northern IN and eventually
western OH. Increasingly widespread thunderstorms and associated
outflow ahead of this complex lends uncertainty to the evolution of
the bow, and the corridor of greatest damaging wind potential.
Refer to MDs #1921 and #1922 for further details.

...OH/WV/KY/VA...
Another linear MCS is affecting southeast OH, and will spread across
WV and into VA later today. The air mass ahead of this complex is
not as unstable, and considerable uncertainty exists regarding this
system's longevity. Nevertheless, sufficient flow aloft and
mesoscale organization will maintain a risk of damaging wind gusts.
Refer to MD #1923 for further details.

...ND/SD/NE...
Moderately strong westerly flow aloft is present today across the
Dakotas, with a moist and unstable air mass in place over the Black
Hills region. This will likely lead to widely scattered
thunderstorm development by early evening. Supercells capable of
large hail and damaging winds are expected. It is unclear how far
southeast these storms will maintain intensity, but model guidance
suggests at least into central SD before weakening overnight.

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Aug 12 00:50:28 2026

ACUS01 KWNS 120050
SWODY1
SPC AC 120048

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0748 PM CDT Tue Aug 11 2026

Valid 120100Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE DAKOTAS AND NORTHERN NEBRASKA...AND FROM NORTHERN ILLINOIS TO
WESTERN NORTH CAROLINA...

...SUMMARY...
Severe storms posing a risk for large hail and damaging winds are
possible into tonight from the Dakotas into the Midwest.

...IL to western NC...

A bowing line of storms from central KY into northeast TN/western VA
will continue to develop southeast the next few hours. A damaging
wind risk will continue with this activity in the short term.
However, convection should begin to wane with southeast extent into
the Appalachians as instability wanes and loss of daytime heating
results in a cooling boundary layer. Convection across KY and
perhaps portions of eastern TN may remain stronger into the evening
given the large reservoir of instability ahead of storms, but
overall expected is for a gradual weakening trend. Reference MCD
1939 for more short term details.

Overnight, most CAMs guidance suggests convection will redevelop
within a warm advection regime across parts of northern IL into IN
and the Ohio Valley. The 00z DVN and ILX RAOBs depict an impressive thermodynamic and kinematic environment. Midlevel lapse rates near 8
C/km amid 40 kt effective shear and MUCAPE near 5000 J/kg with weak
inhibition suggests any storms developing within this environment
could be severe. Convection may develop along the instability
gradient and large hail is possible. If sufficient clustering
occurs, damaging wind also could be possible. As a result, the
Slight (level 2 of 5) risk as been expanded back to the northwest
across northern IL.

...Dakotas into IA...

Supercells across the western Dakotas and far northern NE will
continue to pose a risk for very large hail and damaging gusts the
next few hours. See MCD 1938 for short term information on severe
risk.

It is uncertain how convection will evolve longer-term during the
overnight hours. Some guidance suggests clustering will occur and an
MCS could develop, moving east/southeast across SD/northern NE and
perhaps as far east as IA. Ample west/northwesterly flow aloft is in
place, along with a very moist airmass with strong to extreme
instability. If sufficient clustering can occur, MCS
development/maintenance seems plausible. have expanded the Slight
(level 2 of 5) risk eastward across SD/NE into western IA border
vicinity for this possibility.

..Leitman.. 08/12/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Aug 12 05:16:44 2026

ACUS01 KWNS 120516
SWODY1
SPC AC 120514

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1214 AM CDT Wed Aug 12 2026

Valid 121200Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE
NORTHERN/CENTRAL PLAINS TO THE LOWER OHIO VALLEY...

...SUMMARY...
Thunderstorms with severe gusts and hail will be possible this
afternoon and evening across parts of the central and northern High
Plains. Damaging gusts and isolated hail will also be possible
across parts of the Midwest and Ohio Valley.

...IA to OH Valley...

One or more MCSs migrating through enhanced northwesterly flow aloft
amid a very moist and unstable airmass is possible again today
across the Midwest toward TN. Most forecast guidance suggests an MCS
or thunderstorm clusters could be ongoing over IA at the start of
the period (12z), with warm advection storms arcing across parts of
IL/IN. The early day warm advection storms could develop southeast
across the OH Valley, while the IA MCS develop southeast across the Mid-MS/Lower OH Valley through afternoon. The exact evolution of
convection that is not yet apparent is uncertain, and how outflow
may influence how this activity evolves through the afternoon.
Regardless, the overall environmental parameter space will be
favorable for a damaging wind and isolated hail risk through early
evening.

...Northern/Central Plains...

East/southeasterly low-level flow will maintain modest moisture
across the Dakotas, increasing with southward extent across NE into
northern KS. Near-60 F dewpoints will likely spread westward into
eastern CO/WY/MT. Modest moisture beneath steep midlevel lapse rates
and 30+ kt effective shear magnitudes will support scattered
thunderstorm development across the High Plains. Initial cells will
pose a large hail and damaging wind risk. It is unclear how
convection will evolve with eastward extent across the region as
outflow from prior convection may largely limit stronger
destabilization. A developing low-level jet during the nighttime
hours will be focused across the southern Plains toward KS/southern
NE. This could support some upscale growth potential, but confidence
is low.

...Lower MI into NY/PA/NJ...

A belt of stronger northwesterly flow aloft will extend from Lower
MI into NY/PA today. A seasonally moist/unstable airmass will be in
place. Vertically veering wind profiles will foster 35+ kt effective
shear magnitudes, while hodographs are fairly elongated. Midlevel
lapse rates will remain modest, with MLCAPE around 1000-1500 J/kg
expected. Isolated to widely scattered storms will pose a risk for
damaging gusts and small hail.

...TN Valley/Southeast...

Thunderstorms are expected to develop by midday within a very moist
and strongly unstable airmass. Deep-layer northwesterly flow will
remain weak, but steep low-level lapse rates and PW values near 2
inches could support isolated wet microbursts with stronger
multi-cell clusters.

..Leitman/Moore.. 08/12/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Aug 12 12:38:02 2026

ACUS01 KWNS 121237
SWODY1
SPC AC 121236

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0736 AM CDT Wed Aug 12 2026

Valid 121300Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE
NORTHERN/CENTRAL PLAINS TO THE LOWER OHIO VALLEY...

...SUMMARY...
Scattered severe thunderstorms are possible today through this
evening from parts of the mid Mississippi Valley and lower Ohio
Valley into portions of the central and northern High Plains.
Severe gusts and large hail are the primary hazards.

...IA to OH Valley...
Radar/satellite imagery this morning show several thunderstorm
clusters ongoing from IA into the OH Valley. The most notable
thunderstorm cluster is over far eastern IA and is moving into
central and northern IL this morning. The airmass downstream of
this activity is very moist and extremely unstable [reference the 12
UTC Davenport, IA raob (4300 J/kg MLCAPE)], and it is located near
the terminus of a 35-kt west-southwesterly LLJ over northern MO.
Expecting a gradual intensification of storms this morning across IL
with a risk for scattered severe gusts and associated wind damage. Considerable uncertainty remains regarding the eventual evolution of
additional storm clusters over parts of the Midwest through this
afternoon. Outflow from morning showers/storms over eastern IN into
central KY will likely inhibit appreciable severe risk farther east
across parts of the OH Valley. Nonetheless, a moist and
destabilizing boundary layer will lend a risk for scattered wind
damage and isolated large hail with the stronger storms through the
late afternoon and evening.

...Northern/Central Plains...
East/southeasterly low-level flow will maintain modest moisture
across the Dakotas, increasing with southward extent across NE into
northern KS. Near-60 F dewpoints will likely spread westward into
eastern CO/WY/MT beneath steep lapse rates. Ample heating will
result in moderate buoyancy and 30+ kt effective shear---supporting
some organization to the scattered thunderstorms forecast to develop
later this afternoon/evening. Initial cells will pose a threat for
large hail and severe gusts. Some clustering may occur during the
evening but confidence remains low regarding specific corridors
where the severe threat will focus.

...Lower MI into NY/PA/NJ...
A belt of stronger northwesterly flow aloft will extend from Lower
MI into NY/PA today. A seasonally moist/unstable airmass will be in
place. Vertically veering wind profiles will foster 35+ kt
effective shear magnitudes, while hodographs are fairly elongated.
Midlevel lapse rates will remain modest, with MLCAPE around
1000-1500 J/kg expected. Isolated to widely scattered storms will
pose a risk for damaging gusts and marginally severe hail.

...TN Valley/Southeast...
Thunderstorms are expected to develop by midday within a very moist
and strongly unstable airmass. Deep-layer northwesterly flow will
remain weak, but steepened 0-2 km lapse rates and high PW (near 2
inches) will support an isolated risk for some stronger water-loaded
downdrafts capable of wind damage.

...Lower CO River Valley...
Model guidance shows widely scattered storms developing this
afternoon near a weak upper trough analyzed this morning via
water-vapor imagery. Some of the stronger thunderstorm downdrafts
may be capable of isolated severe gusts.

..Smith/Kerr.. 08/12/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Sep 5 05:24:56 2026

ACUS01 KWNS 050524
SWODY1
SPC AC 050522

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1222 AM CDT Sat Sep 05 2026

Valid 051200Z - 061200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF
THE OHIO VALLEY INTO THE SOUTHERN MID-ATLANTIC AND CAROLINAS...

...SUMMARY...
Severe thunderstorms capable of mainly damaging gusts are possible
across portions of the Ohio Valley into southern Mid-Atlantic and
Carolinas on Saturday afternoon and evening. Isolated occurrences of
large hail and severe wind gusts also appear possible over parts of
the northern and central Plains Saturday into Saturday night.

...Synopsis...

A prominent mid-level ridge will persist over the central CONUS
between upper lows over the Pacific Northwest and the Gulf of St.
Lawrence into NB/NS. Several weak disturbances (some of convective
origin) will progress through the periphery of the ridge, serving as
foci for thunderstorm development. At the surface, an area of low
pressure is forecast over the western Dakotas with an associated
boundary --the location of which may be modified by convective
outflow-- extending into the OH Valley and southern Mid-Atlantic.
The eastern extension of the boundary will begin to push south as a
cold front Saturday afternoon into night as high pressure builds
into the Great Lakes.

...Ohio Valley into the Carolinas...

A mature to decaying MCS is expected to be ongoing 12Z Saturday over
portions of the middle to upper OH Valley, aided by a subtle
mid-level disturbance/possible MCV. There is considerable
variability across the 00Z convection-allowing models in the
longevity and extent of the convective system over the central
Appalachians into southern Mid-Atlantic through the remainder of the
morning. Should the MCS remain intact, isolated occurrences of
damaging wind are possible.

Renewed thunderstorm development is likely by afternoon along the
residual MCS cold pool and/or synoptic front as temperatures in the
90s to around 100 combine with boundary-layer dewpoints in the low
to mid 70s to yield MLCAPE up to 2000-3000+ J/kg with steepening
low-level lapse rates. Additionally, the models indicate some
enhancement of mid-level winds in association with the
disturbance/MCV moving through the southern Mid-Atlantic during the
afternoon, which may yield more organized multicells and line
segments with the predominant hazard being damaging wind gusts into
the evening.

Farther to the west, additional strong to severe storms appear
possible along and ahead of the composite boundary from the vicinity
of the OH River south into the Cumberland Plateau where widely
scattered damaging wind gusts also appear possible.

...Northern and Central Plains...

A band of elevated thunderstorms is expected to be ongoing 12Z
Saturday, centered over eastern SD. That activity is expected to
diminish through the morning with the cessation of the nocturnal
low-level jet; however, isolated occurrences of large hail and
severe wind gusts appear possible prior to dissipation. In the wake
of the early-day storms, the presence of steep low/mid-level lapse
rates and richer boundary-layer moisture with eastward extent will
contribute to a moderately to strongly unstable air mass by
afternoon with MLCAPE of 2000-3500+ J/kg.

Nebulous forcing for ascent and capping relating to the proximity of
the mid-level ridge axis lead to uncertainty in the specific details
regarding the location and extent of surface-based thunderstorm
development during the afternoon into evening. However, the presence
of the surface low, outflow-modified surface front, and a lee trough
over the High Plains will be candidates for storm development. The
strongest deep-layer shear (30-40 kt) is forecast to the north of
the surface low and composite boundary over ND and northern SD into
western MN where a conditional risk of supercells capable of large
hail and severe wind gusts exists. Elsewhere, high-based pulse and
multicell storm modes appear possible with the primary hazard being widely-spaced severe wind gusts.

The isolated severe threat may persist into the overnight hours in
the vicinity of a nocturnally strengthening low-level jet.

...Western Montana...

A belt of enhanced mid/upper-level flow will exist across the
region, to the east of the upper low over the Pacific Northwest.
Heating along the high terrain coupled with the possible influence
of a weak mid-level disturbance is expected to support an increase
in high-based showers and a few thunderstorms during the afternoon
and evening. While lapse rates will be steep with strong deep-layer
shear, the absence of appreciable moisture will limit MLCAPE to
generally less than 250 J/kg. As such the potential for severe wind
gusts is currently too low to warrant 5% wind probabilities.

..Mead/Chalmers.. 09/05/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Sep 5 12:56:50 2026

ACUS01 KWNS 051256
SWODY1
SPC AC 051254

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0754 AM CDT Sat Sep 05 2026

Valid 051300Z - 061200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF
THE OHIO VALLEY INTO SOUTHERN MID-ATLANTIC AND CAROLINAS...

...SUMMARY...
Severe thunderstorms capable of mainly damaging gusts are possible
across portions of the Ohio Valley into southern Mid-Atlantic and
Carolinas this afternoon and evening. Isolated occurrences of large
hail and severe wind gusts also appear possible over parts of the
northern and central Plains today into tonight.

...Ohio Valley into the Carolinas...
An MCS continues to progress southeastward towards the central
Appalachians this morning. The outflow has surged well ahead of the
deep convection along the western edge of this MCS, but remains much
closer to the two primary cores of deep convection along the central
and eastern portions of the MCS. General expectation is for this MCS
to continue southeastward across the central Appalachians and into
the Mid-Atlantic, while the westward-progressing outflow stalls and
loses definition.

Currently, the airmass downstream across the Mid-Atlantic is
characterized by dewpoints ranging from the upper 60s across
northern VA into the mid 70s across southeast NC/eastern SC. Strong
heating is anticipated across much of this region today, with high
temperatures ranging from the low 90s over northern to the upper
90s/low 100s across central/eastern SC. These warm and moist surface
conditions will support moderate to strong afternoon buoyancy,
despite poor mid-level lapse rates. Reintensification and/or renewed thunderstorm development is expected as the MCS (and associated
vorticity maximum) interacts with this destabilized airmass. This
region will be along the southerly periphery of a belt of mid-level northwesterlies, and the resulting vertical shear could help
maintain a favorable cold pool/updraft balance needed to maintenance
of a progressive convective line. Guidance varies on whether one
coherent convective line or a series of smaller bowing segments will
develop, but either case would yield a threat for damaging gusts.
Highest probability for damaging gusts is expected across eastern NC
where the best overlap between buoyancy and vertical is expected.

Additional afternoon development is expected farther west, from the
middle OH Valley through Middle TN, where residual outflow will
likely be present with a destabilized airmass. Weak shear should
limit storm organization but isolated damaging gusts are possible.

...Northern and Central Plains...
Elevated thunderstorms have persisted throughout much of the night
from northeast NE across eastern SD. A second area of thunderstorm
activity exists farther norther across north-central ND. An isolated
instance of hail is possible over both of these regions for the next
few hours before thunderstorm intensity wanes in response to the
cessation of the nocturnal low-level jet.

Despite rising heights throughout the day, most guidance suggests
that low-level convergence along both the lee trough and
outflow-modified front in NE will be sufficient for convective
initiation this afternoon. Limited vertical shear and a deeply mixed
boundary layer suggest an outflow-dominant storm mode with the
primary hazard being widely-spaced severe wind gusts.

Relatively higher thunderstorm coverage is possible across the
central High Plains this evening as warm-air advection supports
additional thunderstorm activity. Some clustering of this activity
is possible, but vertical shear will be weak and overall storm
intensity and organization should be modest.

...Western Montana...
A belt of enhanced mid/upper-level flow will extend across the
region, to the east of an upper low over the Pacific Northwest.
Increasing mid-level moisture and forcing for ascent associated with
a weak mid-level disturbance is expected to support an increase in
high-based showers and a few thunderstorms during the afternoon and
evening. Lapse rates will be steep with strong deep-layer shear, but
the absence of appreciable moisture will limit MLCAPE to generally
less than 250 J/kg. As such the potential for severe wind gusts is
currently too low to warrant 5% wind probabilities.

..Mosier/Lyons.. 09/05/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Sep 5 17:00:28 2026

ACUS01 KWNS 051624
SWODY1
SPC AC 051622

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1122 AM CDT Sat Sep 05 2026

Valid 051630Z - 061200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL APPALACHIANS INTO SOUTHERN VIRGINIA AND THE CAROLINAS...

...SUMMARY...
Strong to severe thunderstorms capable of producing scattered
damaging winds should occur this afternoon/evening across parts of
the central Appalachians into southern Virginia and the Carolinas.
Isolated large hail and severe winds may also occur over parts of
the northern/central Plains through tonight.

...Ohio Valley/Central Appalachians into the Mid-Atlantic and
Carolinas...
An earlier MCS across the OH Valley has weakened as it crossed/moved
eastward over the central Appalachians. The strongest remaining
convective segment is ongoing late this morning across parts of
southwest VA/northeast TN. Robust destabilization is expected to
continue this afternoon downstream of this activity across southern
VA into the Carolinas, with MLCAPE peaking around 2500-3500 J/kg
over central/eastern NC. This region will be on the southern
periphery of modestly enhanced mid-level west-northwesterly flow,
and sufficient deep-layer shear will be present to maintain some
convective organization.

Current expectations are for one or more thunderstorm clusters to
gradually increase in intensity this afternoon as they spread
eastward across southern VA and central/eastern NC, with some
uncertainty whether the ongoing convection will restrengthen, or if
new development will occur along its outflow. Regardless, latest
guidance and observational trends still suggest that a relatively
greater threat for damaging winds should exist this afternoon across central/eastern NC and vicinity, where the greatest thunderstorm
coverage, maxima in MLCAPE/DCAPE, and steepened low-level lapse
rates are forecast. Have therefore introduced higher severe wind
probabilities (30% area) across this region. Isolated hail may also
occur with the strongest cores that can develop, although mid-level
lapse rates are expected to remain rather poor. Severe potential
should gradually wane this evening with the loss of daytime heating,
and as convection moves offshore.

Farther west, outflow from the morning thunderstorms may serve as a
focus for renewed thunderstorm development this afternoon from parts
of the OH Valley southeastward into the TN Valley. This region will
be displaced from the stronger flow aloft present over the Mid-Atlantic/Northeast, with weak deep-layer shear expected. Still,
some risk for isolated damaging winds may exist with any loosely
organized cells/clusters that can develop given the presence of
moderate to locally strong instability.

...Northern/Central Plains...
A highly amplified mid/upper-level ridge will remain anchored over
the central CONUS into south-central Canada through the period, with
generally neutral to weakly rising mid-level heights expected over
the northern/central Plains. Ongoing elevated cells across northern
ND may continue to pose an isolated severe hail threat in the short
term, but weakening low-level warm advection should tend to result
in a further decrease in intensity with this activity. Otherwise,
additional isolated to perhaps widely scattered high-based
thunderstorms may develop this afternoon along/east of a surface lee
trough over the northern/central Plains. While mid-level flow and
related effective bulk shear should remain weak, occasional severe
gusts may still occur with convective downdrafts given a well-mixed
boundary layer. Some risk for hail and gusty winds may also exist
with elevated convection that should eventually develop tonight into
early Sunday morning in a renewed/modest low-level warm advection
regime.

...Western Montana...
To the east of a closed mid-level low over WA/OR, a belt of enhanced southwesterly mid/upper-level winds will extend across the northern
Rockies. Gradually increasing moisture and large-scale ascent aloft
associated with a weak/embedded shortwave trough are expected to
support an increase in isolated thunderstorms this
afternoon/evening. Lapse rates through low/mid levels will be steep
with strong deep-layer shear present, but modest low-level moisture
should limit MLCAPE to generally less than 500 J/kg. The potential
for severe wind gusts still appears too low to justify including 5%
wind probabilities at this time.

..Gleason/Thornton.. 09/05/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Sep 5 20:05:00 2026

ACUS01 KWNS 052002
SWODY1
SPC AC 052000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Sat Sep 05 2026

Valid 052000Z - 061200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CAROLINAS INTO SOUTHEASTERN VIRGINIA...

...SUMMARY...
The threat of strong to severe thunderstorms capable of producing
scattered damaging winds will continue this afternoon/evening across
parts of the Carolinas and southern Virginia. Isolated large hail
and severe winds may also occur over parts of the northern/central
Plains through tonight.

...20Z Update...
Only minor changes were made with this update. The SLGT Risk was
trimmed behind an east-southeastward moving band of convection
moving across the Carolinas. While isolated redevelopment cannot be
entirely ruled out in the wake of this activity, the primary severe
risk will continue spreading eastward to the coast into this
evening.

Farther west, 5-percent hail probabilities were added in parts of
the lower OH Valley. Here, relatively steep deep-layer lapse rates,
around 30 kt of effective shear, and a cellular mode may support
isolated instances of marginally severe hail.

Elsewhere, the previous forecast remains on track.

..Weinman.. 09/05/2026

.PREV DISCUSSION... /ISSUED 1122 AM CDT Sat Sep 05 2026/

...Ohio Valley/Central Appalachians into the Mid-Atlantic and
Carolinas...
An earlier MCS across the OH Valley has weakened as it crossed/moved
eastward over the central Appalachians. The strongest remaining
convective segment is ongoing late this morning across parts of
southwest VA/northeast TN. Robust destabilization is expected to
continue this afternoon downstream of this activity across southern
VA into the Carolinas, with MLCAPE peaking around 2500-3500 J/kg
over central/eastern NC. This region will be on the southern
periphery of modestly enhanced mid-level west-northwesterly flow,
and sufficient deep-layer shear will be present to maintain some
convective organization.

Current expectations are for one or more thunderstorm clusters to
gradually increase in intensity this afternoon as they spread
eastward across southern VA and central/eastern NC, with some
uncertainty whether the ongoing convection will restrengthen, or if
new development will occur along its outflow. Regardless, latest
guidance and observational trends still suggest that a relatively
greater threat for damaging winds should exist this afternoon across central/eastern NC and vicinity, where the greatest thunderstorm
coverage, maxima in MLCAPE/DCAPE, and steepened low-level lapse
rates are forecast. Have therefore introduced higher severe wind
probabilities (30% area) across this region. Isolated hail may also
occur with the strongest cores that can develop, although mid-level
lapse rates are expected to remain rather poor. Severe potential
should gradually wane this evening with the loss of daytime heating,
and as convection moves offshore.

Farther west, outflow from the morning thunderstorms may serve as a
focus for renewed thunderstorm development this afternoon from parts
of the OH Valley southeastward into the TN Valley. This region will
be displaced from the stronger flow aloft present over the Mid-Atlantic/Northeast, with weak deep-layer shear expected. Still,
some risk for isolated damaging winds may exist with any loosely
organized cells/clusters that can develop given the presence of
moderate to locally strong instability.

...Northern/Central Plains...
A highly amplified mid/upper-level ridge will remain anchored over
the central CONUS into south-central Canada through the period, with
generally neutral to weakly rising mid-level heights expected over
the northern/central Plains. Ongoing elevated cells across northern
ND may continue to pose an isolated severe hail threat in the short
term, but weakening low-level warm advection should tend to result
in a further decrease in intensity with this activity. Otherwise,
additional isolated to perhaps widely scattered high-based
thunderstorms may develop this afternoon along/east of a surface lee
trough over the northern/central Plains. While mid-level flow and
related effective bulk shear should remain weak, occasional severe
gusts may still occur with convective downdrafts given a well-mixed
boundary layer. Some risk for hail and gusty winds may also exist
with elevated convection that should eventually develop tonight into
early Sunday morning in a renewed/modest low-level warm advection
regime.

...Western Montana...
To the east of a closed mid-level low over WA/OR, a belt of enhanced southwesterly mid/upper-level winds will extend across the northern
Rockies. Gradually increasing moisture and large-scale ascent aloft
associated with a weak/embedded shortwave trough are expected to
support an increase in isolated thunderstorms this
afternoon/evening. Lapse rates through low/mid levels will be steep
with strong deep-layer shear present, but modest low-level moisture
should limit MLCAPE to generally less than 500 J/kg. The potential
for severe wind gusts still appears too low to justify including 5%
wind probabilities at this time.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Sep 6 00:58:56 2026

ACUS01 KWNS 060058
SWODY1
SPC AC 060056

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0756 PM CDT Sat Sep 05 2026

Valid 060100Z - 061200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTHEAST
COLORADO INTO PARTS OF WESTERN NEBRASKA...INCLUDING THE PANHANDLE...

...SUMMARY...
Widely scattered occurrences of large hail and severe wind gusts are
expected into tonight over northeast Colorado into parts of western
Nebraska, including the Panhandle. Isolated occurrences of large
hail and damaging winds remain possible overnight across a broader
portion of the northern and central Plains. Damaging wind potential
is expected to diminish within the next couple of hours over
portions of Kentucky, Georgia, and South Carolina.

...Northern and Central Plains...

Separate clusters of thunderstorms, including supercells, are
ongoing this evening over the NE Panhandle into northeast CO ahead
of a weak mid-level disturbance moving through WY and north-central
CO. The 00Z LBF sounding sampled relatively steep lapse rates with
MLCAPE of around 2500 J/kg along with a vertically veering wind
profile with around 30 kt of deep-layer shear. As such, expect the
supercell threat to persist for the next hour or two, prior to
storms merging into a larger complex along a nocturnally
strengthening low-level jet. Large hail up to two inches will be the
main hazard in the near-term; however, the potential for severe wind
gusts will become more prevalent if an organized cold pool can
evolve.

Elsewhere, storms are widely scattered across the Dakotas with the
00Z ABR sounding indicating a moderately unstable, but capped air
mass for surface-based parcels. Additional, elevated storms appear
possible overnight along the low-level jet axis with a risk for
isolated occurrence of large hail and damaging wind gusts.

...Central Georgia into southern South Carolina...

Widely scattered thunderstorms are ongoing this evening from south
of Atlanta into southern SC, along an outflow boundary remnant from
storms earlier today. Isolated occurrences of damaging wind gusts
remain possible for the next hour or two before low-level lapse
rates begin to weaken with the loss of daytime heating.

...Kentucky...

A small cluster of thunderstorms has recently intensified south of
the OH River, east of Owensboro, in the vicinity of a weak surface
boundary, and ahead of a weak mid-level disturbance approaching the
area from the north. Regional 00Z soundings indicate the air mass
remains moderately unstable with around 30 kt of deep-layer shear.
The ongoing storms will remain capable of strong wind gusts for the
next hour or so before the boundary layer begins to stabilize.

..Mead.. 09/06/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Sep 6 05:44:02 2026

ACUS01 KWNS 060543
SWODY1
SPC AC 060541

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1241 AM CDT Sun Sep 06 2026

Valid 061200Z - 071200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE SOUTHERN APPALACHIANS INTO THE SAVANNAH RIVER VALLEY AND OVER
PARTS OF WESTERN AND CENTRAL MONTANA...

...SUMMARY...
Widely scattered damaging wind gusts are likely across portions of
the Southeast Sunday afternoon and early evening. Widely scattered
large hail occurrences are expected across portions of western and
central Montana Sunday afternoon and evening. Additional areas at
risk for severe wind and hail are across parts of the Interior West,
over the northern and central High Plains, and from the eastern
Dakotas and western Minnesota into the Ozark Plateau and Gulf Coast
states.

...Synopsis...

A prominent mid-level ridge over the central U.S. is forecast to
weaken during the latter half of the period in response to the
progression of two distinct short-wave troughs and associated wind
maxima through the Interior West. Separate, weaker perturbations
will move through the ridge axis over the northern Plains/mid-MO
Valley region on Sunday, contributing to thunderstorm development in
those areas. Elsewhere, a mid-level disturbance over the OH Valley
Sunday morning is forecast to move into the Cumberland Plateau
vicinity by afternoon, also likely serving as a focus for
thunderstorm development.

At the surface, a lee cyclone will persist over the northern High
Plains, with that feature potentially deepening Sunday night in
response to increasing height falls aloft. High pressure will build
across the Great Lakes, OH Valley, and Northeast with a baroclinic
zone present between those surface features from the mid-MO Valley
through the Ozarks and TN Valley into the Southeast.

...Southern Appalachians into the Savannah River Valley...

Temperatures in the 90s will coincide with boundary-layer dewpoints
in the 70s to yield a moderately to strongly unstable air mass
(i.e., MLCAPE of 2000-3000+ J/kg) by afternoon with steepening
low-level lapse rates. Aided by forcing attendant to the mid-level
disturbance mentioned above, that thermodynamic environment will
support an increase in thunderstorm coverage and intensity through
the afternoon along and ahead of the surface front.

Some increase in mid-level winds may accompany the disturbance with
up to 30 kt of deep-layer shear forecast in the vicinity of the
frontal zone. As such, the potential will exist for longer-lived
multi-cells and line segments capable of damaging wind gusts and
perhaps some large hail into evening.

...Ozark Plateau into the Gulf Coast States...

A similar thermodynamic environment to that previously described is
anticipated ahead of the surface front Sunday afternoon. Generally
weak forcing for ascent and vertical shear are expected to limit the
potential for a more organized severe weather threat. However, the
degree of instability will support briefly intense pulse-type storms
capable of locally damaging wet microbursts during the afternoon and
early evening hours.

...Northern Great Basin into the northern Rockies...

Increasing height falls and strengthening mid/upper-level flow will
overspread the region Sunday afternoon into night ahead of a
vigorous short-wave trough pivoting through the base of the Pacific
Northwest upper low. The strongest instability (i.e., MLCAPE up to
1000-1500 J/kg) is forecast across portions of western into central
MT with stronger capping with eastward extent. The presence of 40-50
kt of deep-layer shear will support supercells capable of mainly
large hail through Sunday evening. While forecast hodographs exhibit considerable curvature/veering winds in the lowest 1-2-km AGL,
stability concerns in the boundary layer may limit severe-wind-gust
and tornado potential.

Weaker instability is forecast from northeast NV and northern UT
into central and eastern ID. However, the presence of steep lapse
rates and kinematics mentioned above may yield a few severe storms
capable of severe wind gusts.

...Northern and central High Plains...

Stronger forcing for ascent is expected to remain to the west and
east of the region through the daylight hours, leading to
uncertainty in storm coverage in the vicinity of the surface low and
lee trough. The 00Z models indicate an increasing potential for at
least isolated thunderstorms from mid-afternoon into evening along
the lee trough. RAP-based forecast soundings show steep lapse rates
and resulting MLCAPE of 1000-2000+ J/kg. The strongest deep-layer
shear of 40-50 kt is forecast across eastern MT into ND with
decreasing magnitudes with southward extent along the lee trough. As
such, a conditional risk for supercells capable of large hail and
severe wind gusts exists. While Marginal Risk wind and hail
probabilities will be maintained with this forecast, an upgrade to
level 2/Slight Risk is possible in subsequent updates.

...Eastern Dakotas and western Minnesota into the lower Missouri
Valley...

Clusters of mainly elevated thunderstorms may be ongoing at 12Z
Sunday, aided by forcing associated with the weak disturbance(s)
cresting the mid-level ridge axis. A subset of the early-day storms
is expected to persist into afternoon with additional storms forming
on the leading edge of more persistent cloud cover, where pockets of
stronger heating and boundary-layer dewpoints in the low/mid 70s
will yield MLCAPE of 1500-2500 J/kg. The 00Z models suggest that
storms will eventually grow upscale into an MCS that tracks south
along or to the immediate cool side of the surface boundary through
portions of the middle and lower MO Valley Sunday afternoon into
evening. It currently appears that deep-layer shear of generally
less than 30 kt and marginally steep mid-level lapse rates may limit
the degree of cold pool organization and a greater/more continuous damaging-wind threat. Nonetheless, the setup appears supportive of
sporadic damaging wind and severe hail occurrences.

..Mead/Chalmers.. 09/06/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Sep 6 12:53:06 2026

ACUS01 KWNS 061252
SWODY1
SPC AC 061251

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0751 AM CDT Sun Sep 06 2026

Valid 061300Z - 071200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE SOUTHERN APPALACHIANS INTO THE SAVANNAH RIVER VALLEY...AND OVER
PARTS OF WESTERN AND CENTRAL MONTANA...

...SUMMARY...
Widely scattered damaging wind gusts are likely across portions of
the Southeast this afternoon and early evening. Widely scattered
large hail occurrences are expected across portions of western and
central Montana this afternoon and evening. Additional areas at risk
for isolated severe wind and hail are parts of the Interior West,
over the northern and central High Plains, and from the eastern
Dakotas and western Minnesota into the Ozark Plateau and Gulf Coast
states.

...Southern Appalachians through coastal SC and GA...
A moist airmass is in place across the region this morning, with
recent surface analysis revealing a reservoir of low to mid 70s
dewpoints. Strong heating is anticipated across this region today,
with afternoon temperatures reaching the low to mid 90s. This strong
heating will destabilize the airmass and contribute to
moderate/strong buoyancy, with MLCAPE around 2000-2500 J/kg likely
during the late afternoon. A subtle shortwave trough will progress
through the northwesterly flow aloft extending over the area,
interacting with this destabilized airmass to support thunderstorm
development. Vertical shear will generally be weak, limiting updraft organization and promoting a predominantly outflow-dominant storm
mode. Even so, steep low-level lapse rates and abundant moisture
will promote the potential for damaging wind gusts with any
longer-lived multi-cells or line segments. Updraft augmentation due
to storm interactions could also result in isolated hail.

...Ozark Plateau into the Gulf Coast States...
A corridor of greater low-level moisture arcs from the Southeast
states through Arkansas and Missouri. Daytime heating will
destabilize this airmass, helping to support thunderstorm
development in areas of low-level confluence. Weak forcing for
ascent and vertical shear are expected to limit storm organization.
However, the degree of instability will support briefly intense
pulse-type storms capable of locally damaging wet microbursts during
the afternoon and early evening hours.

...Eastern Dakotas and western Minnesota into the lower Missouri
Valley...
A linear MCS continues to push eastward across the central Plains
this morning. A notable vorticity maximum has developed within the
northern portion of this line. Its motion appears to be more
northeasterly than the line itself, and new development is occurring
downstream of this vorticity maximum across south-central/southeast
SD and adjacent northeast NE. A corridor of relatively greater
low-level moisture (i.e. dewpoints in the low 70s) exists downstream
of this vorticity maximum and attendant MCS from eastern SD through
western IA and into northern MO. General expectation is for
thunderstorm coverage and intensity to increase later this
morning/early afternoon as the vorticity maximum/remnant MCS
interact with this moist and diurnally destabilizing airmass. Much
of this development is expected to occur along or to the immediate
cool side of the surface boundary that extends through portions of
the middle and lower MO Valley. Occasionally strong updrafts could
result in isolated hail and/or damaging gusts, but the weak
mid-level flow and associated modest deep-layer shear should limit
storm organization and contribute to clustered multicellular mode.

...Northern Plains into the northern/central High Plains...
Modest height falls may begin to impinge on northern/central High
Plains during the early evening as a low-amplitude shortwave trough
moves a belt of stronger southwesterlies just west of the region.
This modest ascent will augment low-level convergence along the lee
trough to support isolated to widely scattered thunderstorm
development where the lingering convective inhibition can be
overcome. This appears most likely across southeast WY and northeast
CO where persistent low-level easterly flow could keep dewpoints in
the 60s. High-based, outflow-dominant storms will support the
potential for isolated strong to severe gusts.

Increasing mid-level flow will support stronger deep-layer vertical
shear farther north (into eastern MT and western ND), but stronger
convective inhibition may linger, casting doubt whether storms will
initiate. If initiation is realized, storm motion could take it into
the more moist and buoyant airmass north of the surface low where
thermodynamic profiles are favorable for large to very large hail.
Will maintain 5% wind/hail probabilities but introduce a CIG1 for
hail given the conditional potential.

...Northern Great Basin into the northern Rockies...
Increasing height falls and strengthening mid/upper-level flow will
spread across the region today ahead of a vigorous shortwave trough
pivoting through the base of a Pacific Northwest upper low.
Thunderstorm development is anticipated over the higher terrain
before then progressing northeastward towards lower elevations.
Deep-layer vertical shear of 40 to 50 kt will support supercells,
with large hail as the primary severe risk. Greater buoyancy is
expected across central MT, but low-level stability will likely
persist across this region as well, potentially limiting the
severe-wind and tornado potential.

Weaker instability is forecast from northeast NV and northern UT
into central and eastern ID. However, the presence of steep lapse
rates and kinematics mentioned above may yield a few severe storms
capable of severe wind gusts.

..Mosier/Lyons.. 09/06/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Sep 6 16:32:26 2026

ACUS01 KWNS 061632
SWODY1
SPC AC 061630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Sun Sep 06 2026

Valid 061630Z - 071200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHEAST...MONTANA...AND NORTH DAKOTA...

...SUMMARY...
Scattered damaging winds should occur across parts of the Southeast
this afternoon/early evening. Scattered large hail is forecast
across portions of Montana and North Dakota this afternoon and
evening. Isolated strong to severe thunderstorms may also occur
today across parts of the northern Great Basin, northern/central
Plains, and Missouri Valley to the Ozarks.

...Southeast/Lower Mississippi Valley...
Recent visible satellite imagery shows mostly clear skies across
GA/SC late this morning, with surface temperatures already in the
mid/upper 80s to low 90s. A weak front is draped from northwest to
southeast from the southern Appalachians to the Atlantic Coast, with
generally low to mid 70s surface dewpoints present to its south.
Continued diurnal heating of this moist airmass will support the
development of moderate to strong instability (greater with
southward/westward extent into GA/AL and north FL). Compared to the
past couple of days, this region will be displaced from the stronger
mid-level west-northwesterly flow present across the
Mid-Atlantic/Northeast. Corresponding deep-layer shear is expected
to remain rather modest (less than 25 kt), with only loosely
organized updrafts forecast. Even with these kinematic limitations,
steepening low-level lapse rates through the afternoon may still
promote isolated to scattered damaging winds with clusters that
develop and spread south-southeastward through the early evening.
Isolated hail may also occur with the more robust cells that can
develop initially. The damaging wind threat should be more isolated
with westward extent into the lower MS Valley compared to GA and the
Carolinas, where the Slight Risk has been maintained with some
expansion.

...Northern Great Basin into the Northern Rockies/High Plains...
A closed mid/upper-level low over the Pacific Northwest and British
Columbia will pivot towards the northern Rockies through the period,
with a belt of enhanced mid-level flow overspreading the northern
Great Basin into the northern Rockies and adjacent High Plains in
MT. At the surface, mostly cloudy conditions are present over much
of western/central MT this morning. Even so, recent NAM/RAP forecast
soundings across this region show supercell profiles later this
afternoon and evening as mid/upper-level winds foster strong
deep-layer shear. Current expectations are for multiple supercells
to develop initially over the higher terrain and spread quickly
northeastward. While there is still some uncertainty regarding
boundary-layer destabilization, sufficient MUCAPE is forecast to
support supercell maintenance into the adjacent High Plains through
the evening. Large hail should be the main threat with this activity
(with some 2+ inches possible given the very favorable deep-layer
shear), but isolated severe gusts may also occur. The Slight Risk
has been adjusted/expanded a little eastward in MT based on latest
short-term guidance trends. High-based thunderstorms may also pose
an isolated threat for severe gusts across parts of the northern
Great Basin this afternoon.

...Northern/Central Plains into the Upper Midwest/Missouri Valley
and Ozarks...
Ongoing and likely elevated supercells with a threat for large hail
across parts of western ND are being aided by a subtle mid-level
shortwave trough cresting the upper ridge that is anchored over the
central CONUS. Favorable lapse rates aloft and modestly enhanced mid/upper-level southwesterly flow is likely supporting updraft organization/intensity with this ongoing activity. The airmass
downstream across central/eastern ND should gradually destabilize
through the afternoon, with a moist low-level airmass present to the
east of a weak surface low over eastern MT/southwest ND/northwest
SD. It remains unclear whether these ongoing supercells will be
maintained farther east across ND, but given the favorable airmass
and sufficient deep-layer shear present, have opted to add a
targeted Slight Risk for the large hail potential.

Additional convection is occurring farther south in SD, southwest
MN/northwest IA, and northeast NE in association with a mid-level
vorticity maximum evident on water vapor satellite imagery moving
eastward across SD/NE. There is a narrow corridor of greater
instability present across this region southward to the Ozarks,
generally along/near a weak surface front. Isolated hail may occur
with the stronger cores in the short term, but it remains unclear if
convection will be able to form into a southward-moving cluster
across eastern NE/western IA later this afternoon and evening. If
this does occur, then a greater threat for severe/damaging winds
would exist. Have deferred a possible upgrade to Slight Risk given
the uncertainty with how ongoing convection will evolve/impact the
developing warm sector, and due to the presence of the large-scale mid/upper-level ridge and generally modest flow aloft. A separate
area of high-based thunderstorms that should develop this afternoon
along/east of a surface lee trough across the central High Plains
could produce occasional hail and severe gusts, even as deep-layer
shear remains modest.

..Gleason/Thornton.. 09/06/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Sep 6 20:02:58 2026

ACUS01 KWNS 062002
SWODY1
SPC AC 062000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Sun Sep 06 2026

Valid 062000Z - 071200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHEAST...MONTANA...AND THE MISSOURI VALLEY...

...SUMMARY...
Scattered damaging winds should occur across parts of the Southeast
this afternoon/early evening. Scattered large hail is forecast
across portions of Montana this afternoon and evening. A focused
corridor for damaging winds and severe hail is forecast across parts
of the Middle and Lower Missouri Valley. Isolated strong to severe thunderstorms may also occur today across parts of the northern
Great Basin, northern/central Plains, and the Ozarks.

...20Z Update...
A Slight Risk was added across parts of the Middle and Lower
Missouri Valley -- driven by 15-percent wind and hail probabilities.
Here, ample diurnal heating amid a very moist air mass is yielding a
corridor of strong surface-based buoyancy (around 4000 J/kg MLCAPE
per the latest HRRR SFCOA data). Large-scale ascent preceding a
convectively augmented midlevel impulse should promote an increase
in storm coverage in this north/south corridor through the
afternoon. The strong buoyancy and around 30 kt of effective shear
should promote a mix of organized clusters and possibly some
supercell structures -- capable of producing damaging wind gusts and
severe hail. See MCD #2253 for more details.

Farther north, the Slight Risk in ND was removed. The latest mode
evolution suggests a reduced hail threat compared to this morning.
However, a locally favorable corridor for damaging wind gusts may
develop into parts of eastern ND this afternoon/early evening.

Elsewhere, the previous forecast remains on track.

..Weinman.. 09/06/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Sun Sep 06 2026/

...Southeast/Lower Mississippi Valley...
Recent visible satellite imagery shows mostly clear skies across
GA/SC late this morning, with surface temperatures already in the
mid/upper 80s to low 90s. A weak front is draped from northwest to
southeast from the southern Appalachians to the Atlantic Coast, with
generally low to mid 70s surface dewpoints present to its south.
Continued diurnal heating of this moist airmass will support the
development of moderate to strong instability (greater with
southward/westward extent into GA/AL and north FL). Compared to the
past couple of days, this region will be displaced from the stronger
mid-level west-northwesterly flow present across the
Mid-Atlantic/Northeast. Corresponding deep-layer shear is expected
to remain rather modest (less than 25 kt), with only loosely
organized updrafts forecast. Even with these kinematic limitations,
steepening low-level lapse rates through the afternoon may still
promote isolated to scattered damaging winds with clusters that
develop and spread south-southeastward through the early evening.
Isolated hail may also occur with the more robust cells that can
develop initially. The damaging wind threat should be more isolated
with westward extent into the lower MS Valley compared to GA and the
Carolinas, where the Slight Risk has been maintained with some
expansion.

...Northern Great Basin into the Northern Rockies/High Plains...
A closed mid/upper-level low over the Pacific Northwest and British
Columbia will pivot towards the northern Rockies through the period,
with a belt of enhanced mid-level flow overspreading the northern
Great Basin into the northern Rockies and adjacent High Plains in
MT. At the surface, mostly cloudy conditions are present over much
of western/central MT this morning. Even so, recent NAM/RAP forecast
soundings across this region show supercell profiles later this
afternoon and evening as mid/upper-level winds foster strong
deep-layer shear. Current expectations are for multiple supercells
to develop initially over the higher terrain and spread quickly
northeastward. While there is still some uncertainty regarding
boundary-layer destabilization, sufficient MUCAPE is forecast to
support supercell maintenance into the adjacent High Plains through
the evening. Large hail should be the main threat with this activity
(with some 2+ inches possible given the very favorable deep-layer
shear), but isolated severe gusts may also occur. The Slight Risk
has been adjusted/expanded a little eastward in MT based on latest
short-term guidance trends. High-based thunderstorms may also pose
an isolated threat for severe gusts across parts of the northern
Great Basin this afternoon.

...Northern/Central Plains into the Upper Midwest/Missouri Valley
and Ozarks...
Ongoing and likely elevated supercells with a threat for large hail
across parts of western ND are being aided by a subtle mid-level
shortwave trough cresting the upper ridge that is anchored over the
central CONUS. Favorable lapse rates aloft and modestly enhanced mid/upper-level southwesterly flow is likely supporting updraft organization/intensity with this ongoing activity. The airmass
downstream across central/eastern ND should gradually destabilize
through the afternoon, with a moist low-level airmass present to the
east of a weak surface low over eastern MT/southwest ND/northwest
SD. It remains unclear whether these ongoing supercells will be
maintained farther east across ND, but given the favorable airmass
and sufficient deep-layer shear present, have opted to add a
targeted Slight Risk for the large hail potential.

Additional convection is occurring farther south in SD, southwest
MN/northwest IA, and northeast NE in association with a mid-level
vorticity maximum evident on water vapor satellite imagery moving
eastward across SD/NE. There is a narrow corridor of greater
instability present across this region southward to the Ozarks,
generally along/near a weak surface front. Isolated hail may occur
with the stronger cores in the short term, but it remains unclear if
convection will be able to form into a southward-moving cluster
across eastern NE/western IA later this afternoon and evening. If
this does occur, then a greater threat for severe/damaging winds
would exist. Have deferred a possible upgrade to Slight Risk given
the uncertainty with how ongoing convection will evolve/impact the
developing warm sector, and due to the presence of the large-scale mid/upper-level ridge and generally modest flow aloft. A separate
area of high-based thunderstorms that should develop this afternoon
along/east of a surface lee trough across the central High Plains
could produce occasional hail and severe gusts, even as deep-layer
shear remains modest.

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Sep 7 00:42:32 2026

ACUS01 KWNS 070042
SWODY1
SPC AC 070040

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0740 PM CDT Sun Sep 06 2026

Valid 070100Z - 071200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
WESTERN AND CENTRAL MONTANA AND OVER A SMALL PART OF THE LOWER
MISSOURI VALLEY...

...SUMMARY...
Widely scattered large hail occurrences with hailstones up to two
inches are expected over portions of western and central Montana
this evening into tonight. More sporadic occurrences of large hail
and severe wind gusts appear possible over the northern and central
High Plains, and across parts of the lower Missouri Valley.

...Northern Rockies into the northern Plains...

Separate vorticity lobes and associated wind maxima will progress
into the northern Rockies and northern High Plains tonight with a
resultant zone of height falls/forcing for ascent overspreading the
region. In the lower levels, a surface cyclone will be maintained
over southeast MT while a nocturnal jet develops over the northern
and central High Plains.

Thunderstorms currently intensifying over western MT are expected to
increase in coverage and intensity while spreading into
north-central MT ahead of the western vorticity lobe rounding the
base of the Pacific Northwest upper low. While the boundary layer is
somewhat cool/stable, the presence of steep mid-level lapse rates,
MUCAPE up to 1000-1500 J/kg, and 40-45 kt of effective bulk shear
will be supportive of supercells with the primary hazard being large
hail up to two inches.

Farther east, isolated to widely scattered storms have developed
along and ahead of a lee trough and the MT surface low from western
ND into northeast CO within a steep lapse rate and moderately
unstable environment (see the 00Z UNR and LBF soundings). Veering
winds with height with up to 35-40 kt of deep-layer shear are
sufficient to support an observed supercell storm mode with the
primary hazards being large hail potentially in excess of two inches
and locally severe wind gusts. A tornado was recently reported with
a slow-moving supercell over McKenzie County, ND. However, sizable temperature-dewpoint spreads within the inflow air mass, and the
tendency for increasing convective inhibition in the coming hours
are likely to limit a continuing tornado threat despite increasing
low-level shear.

Storm coverage is expected to remain limited through the remainder
of the evening with a potential increase later tonight with the
arrival of the eastern vorticity lobe and strengthening low-level
jet. As such, the threat for sporadic large hail and severe wind
gust occurrences may linger into the overnight hours from eastern MT
into the western parts of the Dakotas and NE.

For additional information, see recently issued mesoscale discussion
#2259.

...Lower Missouri Valley...

Widely scattered strong to severe storms are ongoing this evening
over parts of southeast NE, northeast KS, and northwest MO with
activity focused along outflow boundaries and a synoptic front in
the area. The inflow air mass remains hot and relatively moist as of
00Z with observed soundings indicating steep low-level lapse rates
with MLCAPE up to 1500-3000 J/kg. The 00Z TOP sounding sampled
around 30 kt of deep-layer shear, which will remain supportive of
episodic supercell structures for the next couple of hours with an
associated risk for large hail and locally damaging wind gusts.

For additional information, see recently issued mesoscale discussion
#2258.

..Mead.. 09/07/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Sep 7 05:58:18 2026

ACUS01 KWNS 070556
SWODY1
SPC AC 070555

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1255 AM CDT Mon Sep 07 2026

Valid 071200Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTHWEST
INTO CENTRAL NORTH DAKOTA AND SOUTHEAST SOUTH DAKOTA INTO NORTHEAST
NEBRASKA...

...SUMMARY...
Widely scattered severe storms capable of mainly large hail are
expected over portions of northwest and central North Dakota and
southeast South Dakota into northeast Nebraska Monday afternoon into
evening. A tornado or two is possible in southeast South Dakota. A
broader area of isolated large hail and damaging wind potential
exists over the northern and central Plains into upper Mississippi
Valley. Locally damaging wind gusts appear possible over the central
Gulf Coast states Monday afternoon and evening.

...Synopsis...

A vigorous short-wave trough will pivot from the northern Rockies
through the northern High Plains with an associated strengthening of
the mid/upper-level wind field forecast across the northern Plains
into the upper MS Valley. A low-level jet (LLJ) will also be
sustained over the northern and central Plains into upper MS Valley
ahead of a surface cold front advancing through the northern Plains
and central High Plains.

...Northern and central Plains into the upper Mississippi Valley...

Clusters of mainly elevated thunderstorms may be ongoing at 12Z
Monday from eastern MT into the Dakotas within a zone of forcing for
ascent preceding a lead, mid-level disturbance and coincident with
the exit region of the LLJ. The presence of steep mid-level lapse
rates, MUCAPE of 1000-1500 J/kg, and 35-45 kt of effective bulk
shear will be supportive of some storm organization with an
associated risk for isolated large hail occurrences through the
morning hours as that convective regime shifts east across the
Dakotas.

On the periphery of more persistent cloudiness associated with the
morning storms, stronger insolation coupled with dewpoints in the
upper 60s to low 70s F and modestly steep mid-level lapse rates are
expected to yield a moderately unstable air mass by mid to late
afternoon with MLCAPE up to 1500-2500+ J/kg and a weakening cap.
Surface-based thunderstorm development will become increasingly
likely at that time, aided by increasing height falls attending the
primary short-wave trough.

The 00Z models indicate one potentially favored location for storm
development over portions of south-central and southeast SD into
northeast CO, from the vicinity of a secondary surface low southwest
along a pre-frontal trough. RAP-based hodographs over southeast SD
indicate considerable veering through the lowest 1-2 km AGL with
effective SRH of 200-300 m2/s2 and effective bulk shear magnitudes
of 40-45 kt, owing to the proximity of the LLJ. Accompanying
thermodynamic profiles suggest modest low-level lapse rates with
some residual capping. However, given surface-based storm initiation
and sustenance, supercells would be likely with an associated large
hail and tornado threat.

A hotter and more well-mixed boundary layer is expected with
southwestward extent ahead of the pre-frontal trough where
high-based storms capable of severe wind gusts and hail appear
possible.

Surface-based storms also appear possible ahead of an occluding
surface low and trailing cold front from northwest into central ND.
While the boundary layer may remain relatively cool from the
early-day storms, cooling mid-level temperatures will effectively
steepen lapse rates, yielding sufficient instability amidst 40-50 kt
of deep-layer layer. As such, supercells appear possible with an
attendant risk for large hail.

...Central Gulf Coast...

A hot and very moist air mass is forecast Monday afternoon ahead of
a weak front pushing into the region from the north with MLCAPE
increasing to 2500-3500 J/kg. Forcing for ascent will remain weak as
will vertical shear; however, the degree of instability and high
moisture content will be supportive of intense pulse storms capable
of damaging wet microbursts from mid-afternoon into evening.

..Mead/Chalmers.. 09/07/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Sep 7 12:46:08 2026

ACUS01 KWNS 071245
SWODY1
SPC AC 071244

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0744 AM CDT Mon Sep 07 2026

Valid 071300Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
NORTH DAKOTA AND SOUTHEAST SOUTH DAKOTA INTO NORTHEAST NEBRASKA...

...SUMMARY...
Widely scattered severe storms capable of mainly large hail are
expected over portions of North Dakota as well as southeast South
Dakota into northeast Nebraska this afternoon into evening. A
broader area of isolated large hail and damaging wind potential
exists over the northern and central Plains into upper Mississippi
Valley. Locally damaging wind gusts appear possible over the central
Gulf Coast states Monday afternoon and evening.

...Northern/Central Plains into the Upper Mississippi Valley...
Early-morning satellite imagery depicts a deep upper trough over the
western CONUS. A trio of notable shortwave troughs are embedded
within this larger troughing, with the lead wave currently
progressing through eastern MT. Expectation is for this lead wave to
continue northeastward into the southern Canadian Prairie Provinces.
Surface low attendant to this lead shortwave is currently over
east-central MT. This low is also forecast to progress northeastward
just ahead of its parent shortwave for much of the day, before then
occluding over southern Saskatchewan this evening.

Showers and thunderstorms are currently ongoing from central MT into
western ND in the vicinity of this surface low, supported by a
combination of warm advection around the low and large-scale ascent
attendant to the shortwave trough. Warm-air advection is also
supporting additional thunderstorms from the NE Panhandle into
central SD. All of this activity is expected to gradually to shift northeastward this morning in tandem with the progression of the
shortwave and its stronger low/mid-level southerly flow. Steep
mid-level lapse rates, MUCAPE of 1000-1500 J/kg, and 35-45 kt of
effective bulk shear could support occasional storm organization
with an associated risk for isolated large hail.

Renewed thunderstorm development is anticipated this afternoon in
several areas in the wake of the morning storms. One area is along a dryline-like surface trough that is forecast to extend from the
occluding low over southern Saskatchewan to another low over western
SD. Strong low-level convergence is likely along this boundary, with
dewpoints remaining in the mid to upper 60s just east of the
boundary. Some convective inhibition may linger, and overall storm
coverage will likely remain isolated to widely scattered as a
result. However, any storms that develop should become supercells
capable of all severe hazards, including very large hail and a brief
tornado.

Another area is over portions of south-central and southeast SD into
northeast CO, from the vicinity of the secondary surface low of
western SD southwest along a pre-frontal trough. Some limited
convective inhibition may remain over this region as well, likely
keeping the overall storm coverage isolated to widely scattered.
Even so, kinematic profiles do support the potential for supercells
with any persistent deep convective, particularly over southeast SD.
Here, the proximity to the low-level jet results in considerable
veering through the lowest 1-2 km AGL, with effective SRH of 200-300
m2/s2 and effective bulk shear magnitudes of 40-45 kt. Primary
severe risk with any supercells is large to very large hail,
although the low-level veering will support some tornado risk as
well.

...Central Gulf Coast...
A hot and very moist air mass is forecast this afternoon ahead of a
weak front pushing into the region from the north with MLCAPE
increasing to 2500-3500 J/kg. Forcing for ascent and vertical shear
will remain weak; however, the degree of instability and high
moisture content will be supportive of intense pulse storms capable
of damaging wet microbursts from mid-afternoon into evening.

..Mosier/Lyons.. 09/07/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Sep 7 16:14:06 2026

ACUS01 KWNS 071613
SWODY1
SPC AC 071612

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1112 AM CDT Mon Sep 07 2026

Valid 071630Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING OVER PARTS OF CENTRAL NORTH DAKOTA AND SOUTHEAST SOUTH
DAKOTA...

...SUMMARY...
Widely scattered severe storms capable of mainly large hail are
expected over portions of North Dakota as well as southeast South
Dakota into northeast Nebraska this afternoon into evening. Isolated
damaging wind potential will exist over the northern and central
Plains into upper Mississippi Valley. Locally damaging wind gusts
appear possible this afternoon over the central Gulf Coast states.

...ND...
A fast-moving shortwave trough currently over WY/MT will track
northeastward into the Dakotas this afternoon. Strong
heating/mixing in southwest ND will lead to a sharpening dryline
across central ND by mid/late afternoon. This will be the likely
focus for thunderstorm development after 22z. Forecast soundings in
the warm-sector east of the dryline suggest sufficient low-level and
deep-layer shear for supercell storm-modes. Large hail and perhaps a
tornado or two are possible in the most intense storms. This
activity will spread eastward into northeast ND this evening before
weakening.

...CO/KS/NE/SD...
A weak surface boundary is present today from northeast CO into
central NE. Scattered afternoon thunderstorms will form over the
mountains of central CO, with development spreading eastward along
the boundary through the afternoon. Strong heating and a deeply
mixed boundary-layer will promote intense downdrafts in the
strongest cores. By early evening, activity may spread into
southeast SD where greater low-level moisture and CAPE will pose a
risk of a few more intense storms capable of hail or even a tornado.
Recent model solutions have been backing off on this SD scenario,
but will maintain the ongoing SLGT for now.

...LA/MS/AL...
Hot and humid conditions will prevail over the central Gulf coast
region today, with full sunshine and dewpoints in the low-mid 70s.
Steering flow is weak, but high CAPE and ample moisture suggest a
risk of occasional intense downdrafts in the strongest storms.

..Hart/Thornton.. 09/07/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Sep 7 20:01:14 2026

ACUS01 KWNS 072000
SWODY1
SPC AC 071959

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0259 PM CDT Mon Sep 07 2026

Valid 072000Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
CENTRAL NORTH DAKOTA AND SOUTHEAST SOUTH DAKOTA...

...SUMMARY...
Widely scattered severe storms capable of mainly large hail are
expected over portions of North Dakota as well as southeast South
Dakota into northeast Nebraska this afternoon into evening. Isolated
damaging wind potential will exist over the northern and central
Plains into the upper Mississippi Valley. Locally damaging wind
gusts remain possible this afternoon over the central Gulf Coast
states.

...20Z Update...
The MRGL Risk/5-percent wind area was expanded slightly
west-southwestward in parts of eastern MT. Here, a small
north/south-oriented line segment is tracking eastward into an
increasingly warm PBL. This activity will continue to pose a risk of
a few severe wind gusts this afternoon. See MCD #2264 for more
details. Elsewhere, very minimal changes were made with this update.

..Weinman.. 09/07/2026

.PREV DISCUSSION... /ISSUED 1112 AM CDT Mon Sep 07 2026/

...ND...
A fast-moving shortwave trough currently over WY/MT will track
northeastward into the Dakotas this afternoon. Strong
heating/mixing in southwest ND will lead to a sharpening dryline
across central ND by mid/late afternoon. This will be the likely
focus for thunderstorm development after 22z. Forecast soundings in
the warm-sector east of the dryline suggest sufficient low-level and
deep-layer shear for supercell storm-modes. Large hail and perhaps a
tornado or two are possible in the most intense storms. This
activity will spread eastward into northeast ND this evening before
weakening.

...CO/KS/NE/SD...
A weak surface boundary is present today from northeast CO into
central NE. Scattered afternoon thunderstorms will form over the
mountains of central CO, with development spreading eastward along
the boundary through the afternoon. Strong heating and a deeply
mixed boundary-layer will promote intense downdrafts in the
strongest cores. By early evening, activity may spread into
southeast SD where greater low-level moisture and CAPE will pose a
risk of a few more intense storms capable of hail or even a tornado.
Recent model solutions have been backing off on this SD scenario,
but will maintain the ongoing SLGT for now.

...LA/MS/AL...
Hot and humid conditions will prevail over the central Gulf coast
region today, with full sunshine and dewpoints in the low-mid 70s.
Steering flow is weak, but high CAPE and ample moisture suggest a
risk of occasional intense downdrafts in the strongest storms.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Sep 8 01:00:18 2026

ACUS01 KWNS 080059
SWODY1
SPC AC 080058

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0758 PM CDT Mon Sep 07 2026

Valid 080100Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER CENTRAL NORTH
DAKOTA AND SOUTHEAST SOUTH DAKOTA...

...SUMMARY...
The threat for widely scattered severe storms capable of large hail
and perhaps a tornado or two will continue over central North Dakota
and southeast South Dakota into tonight. More isolated occurrences
of large hail and severe wind gusts remain possible this evening
over the central High Plains.

...Northern Plains...

Two separate severe thunderstorm regimes have evolved late this
afternoon into evening. The first is over northwest into central ND,
where widely scattered storms --including a supercell-- are ongoing
ahead of a cold front pushing through western ND. The 00Z BIS
sounding showed modestly steep low-level lapse rates and a moist
boundary layer with MLCAPE CAPE of around 3000 J/kg. The
corresponding wind profile was quite supportive of updraft rotation
with effective SRH of around 300 m2/s2 and 60 kt of effective bulk
shear, suggesting the supercell north of BIS will remain capable of
large hail and a tornado or two for the next hour or two.
Thereafter, increasing convective inhibition may result in the
gradual weakening of the storms with a decreasing severe weather
threat.

For additional near-term guidance on that regime, see recently
issued MCD #2268.

The second thunderstorm regime is evolving across portions of
northeast NE into southeast SD, near the intersection of a
differential heating zone/outflow boundary and a pre-frontal trough.
The boundary layer to the north of the baroclinic zone over
southeast SD is slightly cooler with some convective inhibition
noted in latest objective analysis fields. However, the presence of
MLCAPE up to 2000-3000 J/kg, which coincides with 35-40 kt of
deep-layer shear is supportive of supercells with the primary hazard
being large hail, potentially in excess of two inches. The nocturnal strengthening of the low-level jet is resulting in enlarging
low-level hodographs with effective SRH of 300-400+ m2/s2, per
objective analysis. A tornado recently occurred with the ongoing
storms near the NE-SD border with an additional tornado or two
remaining possible this evening before convective inhibition
increases further.

..Mead.. 09/08/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Sep 8 05:40:22 2026

ACUS01 KWNS 080539
SWODY1
SPC AC 080538

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1238 AM CDT Tue Sep 08 2026

Valid 081200Z - 091200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
IOWA AND EASTERN NEBRASKA...

...SUMMARY...
Widely scattered severe storms capable of mainly severe wind gusts
appear possible across portions of Iowa and eastern Nebraska Tuesday
afternoon and evening. More sporadic occurrences of severe winds and
large hail may occur from portions of the upper Midwest into the
central Plains.

...Synopsis...

An intense upper low moving into southern SK late this evening will
continue northeast through central MB into northern ON ahead of a
secondary short-wave trough tracking from the northern Rockies into
the northern Plains. A belt of enhanced mid/upper-level winds will
be maintained between those features from the northern High Plains
into the upper Great Lakes. At the surface, a cold front will
advance through the eastern Dakotas and upper MS Valley with the
trailing extension of the boundary moving more slowly southeast
through the mid-MO Valley and central High Plains.

...Central Plains into the upper Midwest...

Clusters of thunderstorms are likely to be ongoing at 12Z Tuesday
from portions of the mid-MO Valley into the upper Midwest within a
zone of warm advection and moisture transport along a nocturnal
low-level jet (LLJ). Showers and storms may linger through the
morning across parts of WI and the U.P. of MI, limiting the degree
of air mass destabilization and associated severe weather risk
during the afternoon. Farther to the southwest from IA through
eastern and southern NE into northern KS, stronger daytime heating
on the southern fringe of lingering mid/high-level cloudiness will
contribute to a well-mixed boundary layer, featuring steep low-level
lapse rates. When combined with boundary-layer dewpoints in the 60s
to low/mid 70s F, the air mass is expected to become moderately to
strongly unstable by late afternoon with MLCAPE of 2000-3000 J/kg.

In the absence of appreciable height falls/large-scale forcing for
ascent, convergence along the front and any preceding confluence
zones/outflow boundaries is expected to foster a gradual increase in
storm coverage and intensity by mid to late afternoon amidst the
destabilizing air mass. The strongest deep-layer shear is expected
to be displaced to the north of the effective warm sector with
around 30-35 kt forecast along the frontal zone. A largely parallel shear-vector orientation with the front suggests that initial storms
should grow upscale into line segments or a broken band with an
associated risk for severe wind gusts from mid afternoon through
evening. Isolated occurrences of marginally severe hail are
possible; however, poor mid-level lapse are expected to limit the
overall threat. The 00Z models do indicate some LLJ enhancement over
central IA by late afternoon into evening, resulting in a corridor
of stronger low-level shear. While a brief tornado or two are
possible, a more robust threat is expected to be limited by largely outflow-dominant storms.

..Mead/Chalmers.. 09/08/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Sep 8 12:33:14 2026

ACUS01 KWNS 081233
SWODY1
SPC AC 081231

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0731 AM CDT Tue Sep 08 2026

Valid 081300Z - 091200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
CENTRAL IOWA AND FAR EASTERN NEBRASKA...

...SUMMARY...
Widely scattered severe storms capable of mainly severe wind gusts
appear possible across portions of Iowa and eastern Nebraska Tuesday
afternoon and evening. More sporadic occurrences of severe winds and
large hail may occur from portions of the upper Midwest into the
central Plains.

...Central Plains into the upper Midwest...
An extensive low-level jet is currently in place from the southern
High Plains through the Upper Midwest. Warm-air advection associated
with this feature is contributing to showers and thunderstorms from
eastern NE through WI and into western Upper MI. This activity is
forecast to gradually shift northeastward this morning while the
embedded storms also gradually diminish in strength. These showers
and thunderstorms, and associated warm low to mid-level
temperatures, are expected to limit destabilization across much of
WI and Upper MI.

Some moderate buoyancy is possible by the early afternoon across MN,
just ahead of a cold front pushing eastward into the region.
Lingering convective inhibition will likely limit convective
initiation, and considerable uncertainty exists regarding
thunderstorm coverage. This uncertainty precludes introducing any
severe probabilities, but the combination of moderate buoyancy and
strong deep-layer shear over the region would support some severe
potential with any updrafts that persist and mature.

Farther south and west (i.e. from IA through eastern/southern NE
into northern KS), stronger daytime heating will contribute to a
well-mixed boundary layer, characterized by steep low-level lapse
rates and dewpoints in the 60s to low/mid 70s F. This air mass is
expected to become moderately to strongly unstable by late afternoon
with MLCAPE of 2000-3000 J/kg. Thunderstorm development is expected
as the southeastward-progressing cold front interacts with this
destabilized and buoyant airmass. The stronger vertical shear will
be displaced north/northeast of the greater buoyancy, but 30 to 35
kt of effective bulk shear is still sufficient for some storm
organization. A largely parallel shear-vector orientation with the
front suggests that initial storms should grow upscale quickly into
line segments or broken bands, with some tendency for undercutting
as well. Even so, a few damaging wind gusts will be possible from
mid afternoon through evening. The low-level jet will increase again
from western KS through central IA this evening resulting in a
corridor of stronger low-level shear. This low-level shear will
support a low-probability tornado risk, but a more robust threat is
expected to be limited by largely outflow-dominant and/or elevated
storms.

...CO Plains into western KS...
Thunderstorm development appears likely across the higher terrain of
central CO as the mid-level flow veers more westerly during the late
afternoon. Moist post-frontal northerly low-level flow is expected
across the CO Plains and western KS this evening, which could result
in enough buoyancy to maintain modest intensity as the central CO
storms progress eastward. High-based storm character and prevailing
steep low-level lapse rates may result in a few stronger gusts as
this cluster moves eastward into western KS.

..Mosier/Lyons.. 09/08/2026

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Sep 8 16:17:44 2026

ACUS01 KWNS 081617
SWODY1
SPC AC 081615

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1115 AM CDT Tue Sep 08 2026

Valid 081630Z - 091200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING FROM SOUTHEAST NEBRASKA ACROSS PARTS OF IOWA...

...SUMMARY...
A few severe storms capable of mainly severe wind gusts appear
possible across portions of Iowa and eastern Nebraska this afternoon
and evening.

...NE/IA...
A broad upper ridge remains over much of the central/southern US,
with moderately strong westerly flow over the northern tier of
states. A baroclinic zone extends across southern NE into central
IA. This feature will be sharpened by differential heating through
the day, and will be the focus for afternoon and evening
thunderstorm development. The strongest cells will be near a 20-30
knot southwesterly low-level jet where warm advection and lift will
aid in convective initiation. Sufficient deep-layer shear will
promote supercell and eventual bowing structures, with damaging
winds be the main concern. Most CAM solutions suggest the majority
of convection will be just north of the surface boundary, which may
limit the overall severe threat. Also, weak mid-level lapse rates
and warm temperatures aloft will tend to diminish the hail risk.

...CO/KS...
Farther southwest, hot surface conditions will result in a deeply
mixed boundary layer. Scattered high-based showers and
thunderstorms are expected to form from eastern CO into
western/central KS, with gusty and occasionally damaging wind gusts
possible.

..Hart/Guyer.. 09/08/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Sep 8 19:49:14 2026

ACUS01 KWNS 081949
SWODY1
SPC AC 081947

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0247 PM CDT Tue Sep 08 2026

Valid 082000Z - 091200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING FROM SOUTHEAST NEBRASKA ACROSS PARTS OF IOWA...

...SUMMARY...
A few severe storms capable of mainly severe wind gusts appear
possible across portions of Iowa and eastern Nebraska this afternoon
and evening.

...20Z Update...
The ongoing forecast remains on track and no changes are needed.

..Wendt.. 09/08/2026

.PREV DISCUSSION... /ISSUED 1115 AM CDT Tue Sep 08 2026/

...NE/IA...
A broad upper ridge remains over much of the central/southern US,
with moderately strong westerly flow over the northern tier of
states. A baroclinic zone extends across southern NE into central
IA. This feature will be sharpened by differential heating through
the day, and will be the focus for afternoon and evening
thunderstorm development. The strongest cells will be near a 20-30
knot southwesterly low-level jet where warm advection and lift will
aid in convective initiation. Sufficient deep-layer shear will
promote supercell and eventual bowing structures, with damaging
winds be the main concern. Most CAM solutions suggest the majority
of convection will be just north of the surface boundary, which may
limit the overall severe threat. Also, weak mid-level lapse rates
and warm temperatures aloft will tend to diminish the hail risk.

...CO/KS...
Farther southwest, hot surface conditions will result in a deeply
mixed boundary layer. Scattered high-based showers and
thunderstorms are expected to form from eastern CO into
western/central KS, with gusty and occasionally damaging wind gusts
possible.

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Sep 9 00:38:18 2026

ACUS01 KWNS 090038
SWODY1
SPC AC 090036

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0736 PM CDT Tue Sep 08 2026

Valid 090100Z - 091200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING
ACROSS PORTIONS OF IOWA...

...SUMMARY...
A few severe storms capable of mainly severe wind gusts appear
possible across portions of Iowa this evening.

...Discussion...
Widely scattered thunderstorm activity continues across the surface
boundary extending from portions of central/southern Iowa into
southern Nebraska and northern/western Kansas. A more organized
cluster is ongoing across portions of south-central Iowa. This
cluster will continue to pose a wind threat for the next couple of
hours before eventually moving southeast into less favorable air
across southeastern Iowa/western Illinois. Additional convection
will evolve overnight with the increasing low-level jet across
central Kansas into southeastern Nebraska and southern Iowa. This
will pose at least some potential for small hail and strong to
severe wind.

Across Colorado, scattered convection is ongoing near the foothills
of the Front Range. Time lagged HRRR/RRFS guidance continues to
suggest that this evolves into a cluster with potential for strong
to severe wind to continue downstream this evening. Though moisture
is limited, very warm surface temperatures and steep low to
mid-level lapse rates are supporting at least marginally unstable
conditions downstream.

..Thornton.. 09/09/2026

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

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