ACUS03 KWNS 181922
SWODY3
SPC AC 181920

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0220 PM CDT Wed Jun 18 2025

Valid 201200Z - 211200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE
NORTHERN PLAINS AND UPPER MIDWEST/GREAT LAKES...

...SUMMARY...
Severe thunderstorms may develop Friday into Friday night across
parts of the northern Plains and upper Midwest.

...Synopsis...
Mid-level ridging will be centered over the northern Plains on
Friday. There is considerable uncertainty regarding evolution of the
ridge with some potential for a mid-level shortwave trough to eject
from a western CONUS trough. The exact evolution of this mid-level
pattern and embedded shortwave troughs will significantly impact
severe weather potential on Friday.

...Northern Great Plains into the Upper Midwest/Great Lakes...
Guidance is in agreement regarding low to mid 70s dewpoints into the
northern Plains by Friday afternoon/evening. As temperatures warm
well into the 90s, very strong to extreme instability is forecast to
develop across much of the northern Plains and Upper Midwest. Storm coverage/location is the primary question given the strong ridging
and strong 700mb temperatures across the region. A surface low is
forecast to develop somewhere near the Black Hills with a warm
frontal zone extending eastward from this surface low. This warm
front will likely be the focus for the most intense severe storm
potential on Friday. A stronger mid-level shortwave trough, as
indicated by the 12Z ECMWF, would likely be a scenario with the
greatest severe weather threat. This would involve supercell
development near the surface low/triple point and extending eastward
along the warm front. Eventual upscale growth into a forward
propagating MCS would be likely during the evening with a track
along this frontal zone. This scenario could have the potential for
an intense MCS capable of significant severe wind gusts.

However, if the mid-level shortwave trough is weaker, storm coverage
may be more isolated as warmer mid-level temperatures prevail. In
this scenario, the environment would still support the potential for
intense storms, but storm coverage would remain questionable.

Regardless of the diurnal threat, the risk will likely persist into
the overnight period across northern Minnesota and northern
Wisconsin as a broad low-level jet strengthens across the Plains and
Upper Midwest. This isentropic ascent, combined with a reservoir of
very strong instability and steep lapse rates will support a severe
weather threat through the overnight period.

..Bentley.. 06/18/2025

$$

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ACUS03 KWNS 190731
SWODY3
SPC AC 190730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Thu Jun 19 2025

Valid 211200Z - 221200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE
NORTHERN PLAINS INTO THE UPPER MIDWEST AND GREAT LAKES...

...SUMMARY...
Strong to locally severe storms are possible Saturday from the
northern Great Plains into the Upper Midwest and Great Lakes.

...Synopsis...
The large-scale pattern on Saturday will not change appreciably,
with a seasonably deep upper trough over the West, and an amplified
upper ridge over the Southeast and Ohio Valley. A lee trough and
surface low will remain in place over the central/northern High
Plains, with an expansive area of rich low-level moisture east of
the low/trough across the Plains and upper Midwest.

...Upper Midwest/Great Lakes...
Confidence is quite low regarding the details of severe-storm
potential on Saturday, though conditional potential remains evident
along the periphery of the upper ridge. An MCS that may develop late
on D2/Friday may be moving across parts of the northern Great Lakes
at the start of the period (and possibly posing a severe-wind
threat), though it is possible that the bulk of this MCS will be in
Ontario through the day. This MCS (or its remnant MCV) may move
southeastward toward the lower Great Lakes and NY/PA by evening, and
could pose some severe threat if it does not become displaced from
the buoyancy reservoir to its southwest.

Some redevelopment cannot be ruled out in the wake of the potential
morning MCS into the upper Great Lakes/Midwest. Buoyancy and shear
will remain favorable for organized severe storms, but confidence is
low regarding coverage and location at this time.

...Northern Plains...
Strong storms that develop on D2/Friday be ongoing Saturday morning
across eastern MT, and could pose an isolated severe hail/wind
threat. Guidance varies regarding instability/moisture across
eastern MT later in the day, but if some diurnal destabilization can
occur, then ascent related to the western trough may aid in
additional strong storm development.

Stronger instability will reside across the Dakotas, and the
greatest relative threat for a couple supercells and/or an organized
storm cluster currently appears to be across parts of ND during the
afternoon and evening. However, confidence is too low for higher
probabilities at this time.

..Dean.. 06/19/2025

$$

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ACUS03 KWNS 191926
SWODY3
SPC AC 191925

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0225 PM CDT Thu Jun 19 2025

Valid 211200Z - 221200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE
NORTHERN TIER OF STATES FROM EASTERN MONTANA INTO NEW YORK...

...SUMMARY...
Strong to locally severe storms are possible Saturday from the
northern Great Plains into the Upper Midwest and Great Lakes.

...Synopsis and discussion...
On Saturday, an upper low will move from ID into Canada, with a mean
trough over the Northwest. A belt of strong flow aloft will remain
from the eastern Great Basin into eastern MT, coincident with a
tight midlevel temperature gradient. At the surface, low pressure
will extend from MN into the central High Plains, with drier
westerly winds from MT into the Dakotas.

To the east, an upper high will remain situated over the TN Valley,
with ridge building northward across the Great Lakes and parts of
the Northeast. While early day storms are possible in a warm
advection zone from northern WI across MI and into northern OH, the
rising heights associated with this ridge will likely allow these
storms to dissipate by late morning.

Late day/evening storms may develop over parts of NY into southern
New England beneath northwest flow aloft, and this development will
be aided by theta-e advection at 850 mb out of the west. Given this
influx of instability, potential will exist for isolated marginal
storms with hail or gusty winds.

To the west, while the upper Great Lakes/upper MS Valley region will
be quite unstable, daytime/evening development is less certain given
the upper ridge and minimal lift. However, hot temperatures near the
surface trough could be a favored area of isolated development.
Locally damaging gusts or marginal hail would be the most likely
threats.

..Jewell.. 06/19/2025

$$

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ACUS03 KWNS 200731
SWODY3
SPC AC 200730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Fri Jun 20 2025

Valid 221200Z - 231200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL NE
INTO NORTHWEST IA...THE EASTERN DAKOTAS...AND WESTERN/CENTRAL MN...

...SUMMARY...
Severe thunderstorms may develop on Sunday from parts of the central
and northern Plains into the upper Midwest.

...Synopsis...
A mid/upper-level shortwave trough and attendant jet maximum are
forecast to move from the central Rockies towards the northern Great
Plains on Sunday. A surface low will move from NE/SD northeast
toward Lake Superior, as a trailing cold front moves through parts
of the northern/central Plains. Downstream, an upper ridge will
amplify further across the eastern CONUS through the day, as a
shortwave trough initially over New England moves offshore.

...Great Plains into the Upper Midwest...
Strong to extreme instability is again forecast to develop
along/ahead of the cold front across parts of the central/northern
Plains into the Upper Midwest. Guidance generally suggests that
stronger ascent and deep-layer flow associated with the ejecting mid/upper-level shortwave trough may lag behind the front, resulting
in some uncertainty regarding the magnitude and coverage of the
severe threat. However, strong diurnal heating will support
potential for storm development in the vicinity of the front, and
also southward along a surface trough into the central and perhaps
southern High Plains.

Given the magnitude of instability, deep-layer shear will be
sufficient for some storm organization, with a few strong cells or
clusters possible. A Slight Risk has been added from central NE into
MN, where confidence is currently greatest in development of widely
scattered strong to severe storms during the afternoon and evening.
Convection may persist into late Sunday night, with an isolated
severe threat spreading gradually eastward.

Isolated severe storms will also be possible within the post-frontal
regime across the central/northern High Plains, though guidance
varies regarding the magnitude of MUCAPE in this region. High-based
storms may develop into parts of the southern High Plains, with a
threat of isolated strong to severe gusts.

...Parts of the Northeast/New England...
Guidance varies substantially regarding the strength/timing of the
shortwave trough and related flow fields that will move across New
England Sunday morning. Depending on the strength of the system and
the evolution of convection on D2/Saturday, there is some potential
for isolated strong to severe storms Sunday across the region, given
the presence of increasing buoyancy and favorable deep-layer shear.
A slower system could result in a more robust diurnal threat, while
a faster system may confine the primary threat to the morning.

..Dean.. 06/20/2025

$$

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ACUS03 KWNS 201856
SWODY3
SPC AC 201855

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0155 PM CDT Fri Jun 20 2025

Valid 221200Z - 231200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL
NEBRASKA INTO THE UPPER MIDWEST...

...SUMMARY...
Severe thunderstorms may develop on Sunday from parts of the central
and northern Plains into the upper Midwest.

...Synopsis...
A strong mid-level ridge will amplify further across the eastern
CONUS on Sunday with a weak mid-level shortwave trough traversing
the northeast. A trough across the west will start to weaken and
move into the northern Plains during the period. At the surface,
troughing will extend along a frontal zone from northern Minnesota
to the central High Plains on Sunday.

...Great Plains into the Upper Midwest...
Very strong to extreme instability is forecast to develop across the
central and northern Plains on Sunday. However, very warm low-mid
level temperatures should keep the warm sector mostly capped for
much of the day. Therefore, thunderstorm development should be
mostly confined to the front. However, even along the frontal zone,
storm coverage may be mostly isolated given that forcing from the
mid-level trough may remain mostly northwest of the frontal zone. In
addition, the strong mid-level flow is forecast to remain mostly
post-frontal which may limit storm organization across Nebraska and
South Dakota.

Given the somewhat decoupled upper-level and low-level pattern, the
severe storm threat is more conditional across eastern South Dakota,
Nebraska, and southwest Minnesota with the higher probability storm
threat across eastern North Dakota and northern Minnesota where
cooler temperatures aloft, stronger shear, and stronger forcing
should be present. Severe wind gusts would be the most likely threat
from this activity.

...Parts of the Northeast...
Storms may be ongoing at the beginning of the period across the
Northeast as a mid-level shortwave trough shifts southeast. These
storms could be marginally severe with some damaging wind threat. In
the wake of this convection, very strong to extreme instability is
expected to build into the Northeast, but very warm lower
tropospheric temperatures and building heights aloft should suppress
additional afternoon thunderstorms.

..Bentley.. 06/20/2025

$$

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ACUS03 KWNS 210731
SWODY3
SPC AC 210730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Sat Jun 21 2025

Valid 231200Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
UPPER MIDWEST AND NORTHERN GREAT LAKES...

...SUMMARY...
Strong to potentially severe storms may develop Monday from parts of
the Great Lakes into the central Plains.

...Synopsis...
Little change to the large-scale pattern is expected on Monday, with
a persistent upper trough over the western CONUS, and an amplified
upper ridge covering much of the East. A shortwave ejecting from the
western trough is forecast to move quickly northeastward toward
Hudson Bay by Monday evening. In the wake of this feature, guidance
generally depicts only low-amplitude vorticity maxima moving around
the periphery of the ridge from the central/southern Plains into the
Great Lakes.

At the surface, a front is forecast to be draped from the central
Plains into the Great Lakes. The northeast portion of this front may
continue to move eastward through the day, as a surface low moves
across Ontario. To the southwest, the front may stall or begin to
move northward as a warm front, as a weak surface wave persists over
the central High Plains.

...Upper Midwest/Great Lakes...
Potential for extensive convection on D2/Sunday creates some
uncertainty regarding frontal position on Monday. Locally strong
storms may be ongoing Monday morning, with a general increase in
storm coverage expected during the afternoon where strong heating is
realized in the vicinity of the front. Stronger deep-layer flow will
again be displaced to the cool side of the front, but 30-40 kt of
midlevel flow overlapping moderate to strong buoyancy will support
some potential for organized storms. Mostly unidirectional
southwesterly flow could support one or more forward-propagating
clusters, with a threat of damaging wind and isolated hail.

...Central Plains vicinity...
Deep-layer flow/shear will be somewhat weaker across parts of the
central Plains, compared to areas farther northeast. However, strong
heating will result in development of moderate to locally strong
instability. Scattered storm development is expected within a weakly
capped environment, and a few modestly organized cells/clusters
could evolve with time, posing a threat for strong to severe gusts
and isolated hail.

Some westward moisture transport will be possible into parts of the
central High Plains and Front Range, within a post-frontal regime.
Isolated storms may develop within this regime, though generally
modest midlevel lapse rates may tend to limit robust
destabilization.

...Northern New England...
Strong to extreme instability will again reside across parts of the
Northeast and New England Monday afternoon, along the northern
periphery of the upper ridge. However, the influence of the upper
ridge is still expected to limit storm potential through the day.
This region will continue to be monitored for the possibility that
storms developing across Quebec may affect parts of northern New
England, though this scenario is too uncertain for severe
probabilities at this time.

..Dean.. 06/21/2025

$$

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ACUS03 KWNS 211914
SWODY3
SPC AC 211914

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0214 PM CDT Sat Jun 21 2025

Valid 231200Z - 241200Z

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

...SUMMARY...
Strong to potentially severe storms may develop on Monday, from
parts of the Great Lakes into the central Plains.

...Synopsis...
Broad mid-level troughing across the western U.S., as well as upper
ridging across the eastern CONUS, will remain in place Monday. The
embedded mid-level shortwave trough and associated surface low over
the northern U.S. on Day 2 (Sunday) will eject into Ontario on
Monday. As such, overall synoptic ascent will decrease across the northern/central CONUS through the period. Nonetheless, surface lee
troughing and a trailing frontal boundary will serve as the impetus
for thunderstorm development across parts of the Great Lakes into
the central Plains, where adequate buoyancy will support strong to
potentially severe thunderstorms.

...Great Lakes/Upper Midwest...
Thunderstorm development is likely along or immediately ahead of the
frontal boundary by Monday afternoon. Deep-layer flow/shear will be
oriented roughly parallel to the surface boundary, encouraging
mainly multicellular/linear structures. 30 kts of effective bulk
shear will be in place, amid 2000 J/kg MLCAPE, driven by 7 C/km
mid-level lapse rates atop 70 F surface dewpoints. As such, the more
robust, longer-lived storms may support a few instances of severe
wind and/or hail.

...Portions of the central Plains...
Thunderstorms may develop immediately along the surface boundary, as
well as behind the front across the central Plains by afternoon peak
heating. Deep-layer shear will be weaker here compared to the Great
Lakes, though low-level lapse rates may be steeper (i.e. over 8.5
C/km), yielding MLCAPE values at least in the 2000-3000 J/kg range.
As such, any of the more intense pulse cellular or multicellular
storms that develop may produce few severe gusts.

...New England...
Strong to locally extreme buoyancy, driven by a residual EML, will
meander over the Mid Atlantic to New England on Monday as a surface
anticyclone and associated upper ridge remains in place. Upper
support is lacking for appreciable thunderstorm development. Some of
the latest guidance suggests that strong thunderstorm potential will
be confined to the periphery of the upper ridge over central Quebec.
However, thunderstorm probabilities have been maintained given the
possibility of a trailing stray storm over southern Quebec
potentially impinging on northern New England.

..Squitieri.. 06/21/2025

$$

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ACUS03 KWNS 220731
SWODY3
SPC AC 220730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Sun Jun 22 2025

Valid 241200Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE NORTHERN/CENTRAL HIGH PLAINS...

...SUMMARY...
Severe storms are possible Tuesday from eastern Wyoming into
southwest South Dakota, the Nebraska Panhandle, and northeast
Colorado. Isolated strong to severe storms will also be possible
from parts of the central Plains and Midwest into the Northeast.

...Synopsis...
Little change to the large-scale pattern is expected on Tuesday. An
upper trough will remain in place over the West, while an expansive
upper ridge will persist from the southern Plains into the eastern
CONUS. A cold front will move southward across parts of the
Northeast and New England. Farther west, an outflow-influenced front
will be draped from central Plains into the Great Lakes, with the
western portion of this front potentially moving northward as a warm
front across the central/northern High Plains.

...Central/northern High Plains vicinity...
A gradual increase in low-level moisture is expected into parts of
the central/northern High Plains and adjacent high terrain areas on
Tuesday. Moderate instability may develop by afternoon, with
scattered storm development possible. This region will be on the
periphery of stronger southwesterly flow aloft associated with the
western trough. However, veering wind profiles will provide
sufficient deep-layer shear for storm organization, including
potential for supercells capable of large hail, localized severe
gusts, and possibly a tornado. Some upscale growth is possible into
the evening as convection moves into lower terrain, though the
severe threat with this scenario is more uncertain.

A Slight Risk has been added where wind profiles appear most
favorable for supercells, from eastern WY into the central High
Plains.

...Central Plains into the Upper Midwest...
Scattered diurnal storm development will again be possible from the
central Plains into the Great Lakes, with the greatest coverage in
the vicinity of the front. Guidance generally suggests that
low/midlevel flow may be slightly weaker compared to D2/Monday, but
moderate to strong buoyancy will still support some potential for
strong to locally severe storms. Loosely organized cells/clusters
will be capable of producing at least isolated damaging wind, and
perhaps some hail.

...Lower Great Lakes into New England...
Strong instability will likely develop along/south of the advancing
cold front from the lower Great Lakes region into New England. A
shortwave trough moving eastward across northern Ontario/Quebec will
result in some dampening of the upper ridge in this region, though
the strongest deep-layer flow and large-scale ascent is expected to
be displaced north of the front. Effective shear will be sufficient
for some storm organization, though coverage of storm development
remains uncertain at this time. A Marginal Risk has been included
for this area, and greater severe probabilities may eventually be
needed if trends support more than isolated storm coverage.

..Dean.. 06/22/2025

$$

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ACUS03 KWNS 221922
SWODY3
SPC AC 221921

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0221 PM CDT Sun Jun 22 2025

Valid 241200Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER EASTERN
WYOMING AND VICINITY...

...SUMMARY...
Severe storms are possible Tuesday from eastern Wyoming into
southwest South Dakota, the Nebraska Panhandle, and northeast
Colorado. Isolated strong to severe storms will also be possible
from parts of the central Plains and Midwest into the Northeast.

...Synopsis...
The upper ridge over the East will flatten on Tuesday as a strong
upper trough moves across Ontario and Quebec, with the strongest
height falls occurring overnight. To the west, shortwave ridging
will occur over the northern Plains during the day, as a weakening
and low-amplitude wave moves from UT into WY through 00Z. This
system will continue into the northern Plains overnight, providing
cooling aloft.

At the surface, high pressure will extend from the upper Great Lakes
into the Southeast, with southerly winds persisting over the Plains.
A boundary from Lower MI into NE will surge north as a warm front
late in the day and overnight, with backed/easterly winds along this
front allowing for near 60 F dewpoints as far west as eastern WY.

Late in the day, a cold front associated with the Quebec upper
trough will push south across NY, PA, and New England, providing a
focus for storms as the antecedent air mass will be unstable.

...Northern to central High Plains...
Morning thunderstorms may be ongoing from parts of NE and KS
northeastward into Lower MI, but probably not severe at that time.
As heating occurs, re-development is possible, both along the
developing warm front or with any MCVs or residual outflow
boundaries. The weak shear environment coupled with moderate
instability will primarily yield sporadic clusters of strong to
locally damaging wind gusts.

Farther west into eastern WY and northeast CO, supercell potential
will exist late in the day and during the evening, as moist easterly
flow eventually becomes uncapped generally east of a Casper to
Cheyenne to Denver line. Aided by steep lapse rates/heating over the
higher terrain, and the approaching upper trough, widely scattered
cells are anticipated, with large hail the most likely threat. A
brief tornado cannot be ruled out. While capping will be an issue
after dark, the lifting warm front may support additional storms
into western SD/NE.

...Northeast Late Afternoon/Evening...
Forecast soundings across the area depict relatively warm profiles
aloft, though still unstable with 1500-2000 J/kg MUCAPE. Given this,
widely scattered thunderstorms are expected from Lake Huron eastward
into parts of New England late in the day. As these storms should be
timed near peak heating, localized strong downbursts will be
possible.

..Jewell.. 06/22/2025

$$

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ACUS03 KWNS 230743
SWODY3
SPC AC 230742

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0242 AM CDT Mon Jun 23 2025

Valid 251200Z - 261200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN A CORRIDOR
FROM THE NORTHERN HIGH PLAINS INTO THE MIDWEST AND NORTHEAST...AND
ALSO ACROSS PARTS OF THE SOUTHEAST...

...SUMMARY...
Strong to potentially severe storms are possible Wednesday in a
corridor from the northern High Plains into the Midwest and
Northeast, and also across parts of the Southeast.

...Synopsis...
An upper ridge is forecast to persist across parts of the Ohio
Valley and Southeast on Wednesday, with some gradual weakening of
the ridge expected through the forecast period. Multiple
low-amplitude midlevel shortwave troughs will move along the western
and northern periphery of the ridge, from the central/northern
Plains into the Upper Midwest and Great Lakes. Along the southern
periphery of the ridge, a slow-moving mid/upper-level low will is
forecast to approach Florida from the Bahamas.

...Parts of the central/northern Plains into the Upper Midwest...
A remnant MCS may be ongoing somewhere from the north-central Plains
into parts of southern MN/northern IA Wednesday morning. This system
is currently expected to gradually diminish with time as the
nocturnal low-level jet weakens. A localized severe could accompany
this remnant MCS through part of the morning.

In the wake of this MCS, diurnal heating of a richly moist
environment will support strong destabilization near an
outflow-reinforced front. Storm development will be possible along
this front/outflow by late afternoon, with MLCAPE potentially in
excess of 3000 J/kg supporting vigorous updrafts. Deep-layer flow
will be relatively modest, though locally backed winds near the
boundary could support initial supercell development, before storm
clustering becomes more prominent with time. Damaging winds,
isolated hail, and possibly a tornado could accompany the strongest afternoon/evening storms. A corridor of greater severe probabilities
may eventually be needed, if confidence increases regarding the
evolution of morning convection and placement of remnant surface
boundaries.

Farther west, a relatively moist post-frontal regime could again
support strong to potentially severe storms across parts of the central/northern High Plains. There is some potential for this
region to be in the wake of a departing midlevel shortwave trough
during the afternoon and evening, making diurnal storm coverage
uncertain. Deep-layer shear will be sufficient for at least an
isolated severe threat in the region during the afternoon and
evening.

...Lower Great Lakes into the Mid Atlantic/Northeast...
Scattered storm development will be possible Wednesday afternoon
across parts of the lower Great Lakes into the Mid Atlantic and
Northeast, along/south of a cold front. While temperatures aloft
will be rather warm, diurnal heating will support moderate to
locally strong buoyancy. Deep-layer flow/shear is forecast to be
relatively weak, but unidirectional west-northwesterly flow could
support outflow-dominant clusters capable of at least isolated wind
damage.

...Parts of the Southeast/Carolinas...
A pocket of steep midlevel lapse rates will be in place across parts
of the Southeast and Carolinas on Wednesday. The favorable lapse
rates combined with strong diurnal heating of a very moist airmass
will result in development of strong to extreme instability by
afternoon. With some further weakening of the upper ridge, storm
coverage may increase compared to previous days.

20-30 kt of northeasterly flow aloft will also develop across parts
of the region, to the northwest of the offshore upper low. This
modestly enhanced flow could support at least transient storm
organization within the very unstable environment. Damaging winds
and isolated hail will be possible within this regime. Any loosely
organized clustering could result in localized corridors of more
concentrated wind damage.

..Dean.. 06/23/2025

$$

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ACUS03 KWNS 231931
SWODY3
SPC AC 231930

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Mon Jun 23 2025

Valid 251200Z - 261200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE
NORTHERN/CENTRAL HIGH PLAINS TO THE MIDWEST...GREAT LAKES AND THE MID-ATLANTIC...SOUTHWARD ACROSS THE SOUTHEAST AND INTO FLORIDA...

...SUMMARY...
Strong to potentially severe storms are possible Wednesday in a
corridor from the northern High Plains into the Midwest and
Northeast, and also along and east of the Appalachians into the
Southeast and much of Florida

...Synopsis...
Upper-level ridging across the eastern CONUS will start to weaken on
Wednesday. A weak low will move west across the Florida Peninsula
during the period. A strong mid-level jet streak will extend along
the northeastern periphery of the ridge from northern Ontario to the
Northeast. The trough across the western CONUS will deamplify
through the period with a weak shortwave trough ejecting into the
Plains.

...Northern/Central High Plains and adjacent Plains...
A deepening surface low will develop across northeast
Colorado/northwest Kansas, and southwest Nebraska on Wednesday as a
mid-level trough ejects over the Plains. Moderate instability is
expected to develop south of the front which will extend east from
this surface low across Nebraska and into Iowa. Isolated to
scattered storms are expected along this front and near the
intersection with the dryline/surface low. While mid-level flow is
forecast to be somewhat weak, stronger upper-level flow may provide
sufficient upper-level venting/deep-layer shear for some supercell organization.

Stronger flow will be present farther north across northeast Wyoming
and southeast Montana. A few supercells are possible if low 60s
dewpoints can advect into the region with moderate instability.

...Midwest to the Mid Atlantic...
Thunderstorms will likely be ongoing at the beginning of the period
from the central Plains to the Great Lakes. These thunderstorms and
their composite outflow will likely reinforce the boundary across
the area. South of this boundary, a very moist airmass with moderate instability will be in place. Very weak shear will be the primary
limiting factor to severe weather, but numerous thunderstorms in a
moderately unstable and very moist environment should support some
threat for wet microbursts and damaging wind gusts.

...Mid-Atlantic to the Southeast and Florida...
Steep mid-level lapse rates are expected across much of the eastern
CONUS on Wednesday as the upper-level ridge weakens. Strong heating
in a very moist environment should result in moderate to strong
instability from Virginia southward into Florida. The highest
confidence for storms will be along the sea breeze and the higher
terrain. However, additional thunderstorms are also possible during
the afternoon, particularly where any remnant outflow boundaries may
remain from Tuesday night thunderstorm activity. Strengthening
northeasterly flow across the region may provide enough shear for a
few strong to severe multicell clusters capable of mostly damaging
wind gusts.

..Bentley.. 06/23/2025

$$

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ACUS03 KWNS 240713
SWODY3
SPC AC 240712

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0212 AM CDT Tue Jun 24 2025

Valid 261200Z - 271200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
THE CENTRAL PLAINS AND MIDWEST...AND OVER MUCH OF THE SOUTHEAST AND
MID ATLANTIC...

...SUMMARY...
Scattered strong storms are possible from the central Plains to
Lower Michigan, over parts of the Southeast, and over parts of
Montana on Thursday. Scattered damaging gusts appears to be the main
concern.

...Synopsis...
On Thursday, a weak upper wave will move eastward across the Great
Lakes, phasing with the larger-scale trough which will be exiting
the Northeast. South of there, a weakening upper low should remain
over FL, providing cool temperatures aloft. Otherwise, winds aloft
over much of the central and eastern CONUS will be weak. To the
west, moderate westerly flow aloft will move across the Pacific
Northwest and into the northern Rockies, with 30-40 kt 500 mb winds
over MT.

At the surface, a large area of moisture and instability will remain
in place from the Plains and Midwest into the Southeast, and this
will continue to support widely scattered thunderstorms, with some
producing severe gusts during the afternoon. Meager moisture return
will occur into eastern MT, in advance of the low-amplitude upper
wave.

...Central Plains into the Midwest...
A surface boundary will provide a focus for daytime redevelopment
from KS IA/MO/IL, with storms becoming numerous by 00Z. Weak shear
and ample moisture should support clusters of storms with primarily
localized strong to damaging gusts.

...Southeast...
Midlevel lapse rates are forecast to weaken on Thursday, but cool
temperatures will still support areas of moderate instability.
Storms should again occur over the Appalachians, and perhaps along
residual outflows from early convection. Isolated damaging gusts
will be possible.

...Eastern MT...
Steep lapse rates will develop, but surface dewpoints are forecast
to be in the 40s F within a pre-frontal trough. Still, the deeply
mixed boundary layer combined with 500-1000 J/kg MUCAPE and modest
westerly flow aloft may support scattered storms capable of locally
strong wind gusts.

..Jewell.. 06/24/2025

$$

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ACUS03 KWNS 241917
SWODY3
SPC AC 241916

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0216 PM CDT Tue Jun 24 2025

Valid 261200Z - 271200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES...FROM THE
MID-ATLANTIC TO THE SOUTHEAST...AND NORTHEAST MONTANA VICINITY...

...SUMMARY...
Scattered strong storms are possible from the central Plains to
Lower Michigan, over parts of the Southeast, and over parts of
Montana on Thursday. Scattered damaging gusts appears to be the main
concern.

...Synopsis...
Somewhat zonal flow is expected across the northern CONUS on Friday
with a broad ridge across much of the southern CONUS. A moderate
mid-level jet streak will move across Montana with relatively weak
flow across the remainder of the CONUS. A weak upper low will drift
slowly northeast across the southeastern CONUS.

...Mid-Atlantic to the Southeast...
A broad area of moderate instability is forecast from the
Mid-Atlantic to the Southeast on Friday. Shear is expected to be
very weak through the period, but moderate instability and
relatively steep mid-level lapse rates beneath the upper low will
provide a thermodynamic environment favorable for some damaging wind
gusts. More focused areas of strong to severe storms may exist near
outflow boundaries from D2/Thursday convection.

...Central Plains to the western Great Lakes...
Moderate to strong instability is forecast to develop along a
frontal zone from Kansas to Wisconsin on Friday afternoon/evening.
Shear is expected to remain weak (20 to 25 knots), but strong
instability will support the threat for some damaging wind gusts.

...Northeast Montana Vicinity...
Moderate mid-level flow is expected to overspread northeast Montana
on Friday where a deeply mixed boundary layer (above 3km) is
forecast. While instability will not be that great due to limited
moisture, it should be sufficient for a few storms. Moderate shear
(25 to 30 knots) and a deeply mixed boundary layer will support a
threat for some severe wind gusts Friday afternoon/evening.

..Bentley.. 06/24/2025

$$

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ACUS03 KWNS 250732
SWODY3
SPC AC 250732

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0232 AM CDT Wed Jun 25 2025

Valid 271200Z - 281200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE
NORTHERN PLAINS...

...SUMMARY...
Severe storms producing large hail and locally damaging winds are
forecast over parts of the northern Plains late on Friday. Sporadic
damaging gusts may also occur over parts of the Mid Atlantic and
Southeast.

...Synopsis...
A low-amplitude shortwave trough will move from MT into the northern
Plains, with 50 kt midlevel flow moving across MD and northern MN.
Cooling aloft will also overspread the area, steepening lapse rates.
Meanwhile, minor height rises will occur over the central and
southern Plains, while a weak midlevel low persists over the
Southeast.

At the surface, robust low-level moisture will remain in place from
the Plains to the East Coast. Southerly winds increasing ahead of
the northern Plains wave will aid northward moisture advection east
of a surface trough, which will extend from the central Dakotas into
western NE/KS by late afternoon. During the day, a warm front will
lift across the eastern Dakotas and parts of MN, but cool air should
remain over much of the upper Great Lakes area with weak high
pressure.

...Northern Plains...
Low pressure will deepen from the Dakotas southward toward the
central High Plains, with a wind shift/boundary pushing east into
across the western Dakotas during the afternoon. A plume of steep
low-level lapse rates will develop and nose into central SD, while
dewpoints in the mid to upper 60s F spread into the area as well.
The result will be moderate to strong instability by late afternoon
and evening.

Storms are expected to form within the heated surface trough where
the cap will be zero by late in the day. The strongest storms
capable of significant hail and locally damaging gusts should occur
across the Dakotas through evening, with isolated cells extending
southward into western NE/KS and perhaps far eastern CO. In
addition, elevated severe storms may persist into northwest MN as
the low-level jet increases during the evening, with large hail
potential.

....Southeast into the Mid Atlantic...
Scattered daytime storms will again occur generally east of the MS
River, with focus from the Mid Atlantic across the
Carolinas/Appalachians/Gulf Coast states. Instability will likely
not be as strong as previous days due to several days of overturning
of the air mass, however, pockets of stronger instability will favor
locally damaging gusts from microbursts.

..Jewell.. 06/25/2025

$$

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ACUS03 KWNS 251919
SWODY3
SPC AC 251918

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0218 PM CDT Wed Jun 25 2025

Valid 271200Z - 281200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE
NORTHERN PLAINS...

...SUMMARY...
Severe storms producing large hail and locally damaging winds are
forecast over parts of the northern Plains late on Friday. Sporadic
damaging gusts may also occur over parts of the Mid Atlantic and
Southeast.

...Synopsis...
A broad mid-level trough will shift east across the northern Rockies
on Friday with strengthening mid-level flow overspreading the
northern Plains. This will result in lee troughing from the Canadian
Prairies to the central High Plains. A moist environment will be in
place east of this trough with dewpoints in the 60s.

...Northern Plains...
Moderate to potentially strong instability is forecast across the
northern Plains on Friday with temperatures near 80 and dewpoints in
the 60s. Strengthening mid-level flow should result in ample shear
for supercells by Friday afternoon/evening as ascent increases
across the northern Plains. Significant hail and severe wind gusts
will be the primary threat from this activity. A strengthening/moist
low-level jet may support supercell maintenance through the evening
and perhaps into the overnight period. Even if diurnal storms
dissipate, additional overnight elevated storms are likely across
portions of eastern North Dakota and northern Minnesota amid
strengthening isentropic ascent.

...Mid Atlantic to the Southeast...
Moderate instability is expected to develop across much of the
eastern CONUS on Friday. Instability is not expected to be as strong
as mid-level temperatures will be warmer after Day 1/2 convection
across the region. However, a pocket of relatively cooler air aloft
will exist across the Southeast and into the central Appalachians
and Mid-Atlantic which will support some threat for stronger storms
capable of damaging wind gusts.

..Bentley.. 06/25/2025

$$

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ACUS03 KWNS 260717
SWODY3
SPC AC 260716

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0216 AM CDT Thu Jun 26 2025

Valid 281200Z - 291200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL
NEBRASKA AND EASTERN SOUTH DAKOTA INTO MINNESOTA AND WESTERN
WISCONSIN...

...SUMMARY...
Scattered severe storms with wind and hail potential will be
possible over parts of the northern Plains to upper Mississippi
Valley Saturday afternoon and evening.

...Synopsis and Discussion...
Shortwave ridging will occur over the upper MS Valley during the day
on Saturday, before height falls arrive in association with a
low-amplitude upper trough moving across MT and the Dakotas. This
will allow a large area of moisture and instability to build, with
MUCAPE over 4000 J/kg forecast from the eastern Dakotas into MN and
IA.

A surface trough is forecast to deepen from the eastern Dakotas into
central NE, as southerly winds maintain a northward flux of theta-e
with a deepening moist boundary layer. The end result should be
storms developing within this trough, which will then spread east
and persist through evening.

While shear will not be particularly strong, steep midlevel lapse
rates combined with veering winds with height will favor initial
robust cells capable of large hail and perhaps a brief tornado risk,
before storms form into propagating clusters with damaging winds
likely. The surging theta-e out of the southwest during the evening
may allow severe storms to persist into western WI late.

Elsewhere, widespread moisture and instability will remain over the
Southeast and Mid Atlantic, with scattered clusters of afternoon
storms likely. Pockets of stronger instability may support localized
strong to damaging gusts. Predictability is currently too low to
denote precisely which areas may see a low-end severe gust threat.

..Jewell.. 06/26/2025

$$

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ACUS03 KWNS 261930
SWODY3
SPC AC 261929

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0229 PM CDT Thu Jun 26 2025

Valid 281200Z - 291200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SATURDAY AFTERNOON
INTO SATURDAY NIGHT ACROSS PARTS OF CENTRAL AND EASTERN SOUTH DAKOTA...NORTHEASTERN NEBRASKA...MUCH OF SOUTHERN AND CENTRAL MINNESOTA...ADJACENT NORTHWESTERN WISCONSIN...

...SUMMARY...
Scattered strong thunderstorms, posing a risk for severe hail and
wind, are possible across parts of the middle Missouri Valley into
Upper Midwest Saturday afternoon into Saturday night.

...Discussion...
Little change in the large-scale mid/upper flow is forecast from
Friday into Saturday, with modest westerlies remaining generally
zonal and confined to the northern tier of the U.S. and adjacent
portions of southern Canada. Within this regime, one notable short
wave trough is forecast to progress east of the Great Lakes into New
England Saturday through Saturday night, as broad upstream
troughing (with at least a couple of embedded smaller-scale
perturbations) progresses eastward along the north central
Canadian/U.S. border vicinity.

In lower-levels, cooler and drier boundary-layer air is likely to be
maintained across parts of northern New England, with another influx
of cooler air spreading southeast of the Great Lakes through the
upper Ohio Valley, northern Mid Atlantic coast and southern New
England by late Saturday night. A trailing cold front is likely to
continue slowly advancing east/southeast of the northern Rockies,
through the northern Great Plains. Elsewhere, east of the high
plains, seasonably moist boundary air may become characterized by
moderate to strong potential instability with daytime heating.

...Northern Great Plains...
The extent of convective development and its evolution remain
unclear for this period due to a number of lingering uncertainties.
Focus for renewed thunderstorm development could be impacted by
outflow from convection developing Friday night into early Saturday. Additionally, strongest potential instability by Saturday afternoon
is likely to become focused beneath the nose of the warmer and more
strongly capping elevated mixed-layer air, roughly across the
northern/eastern South Dakota vicinity, before slowly becoming
suppressed southeastward. However, this might tend to become
displaced to the south of the stronger and more favorably sheared
westerlies.

Even so, given thermodynamic profiles becoming characterized by
steep lower/mid-tropospheric lapse rates and large CAPE, scattered
strong to severe thunderstorm development appears possible ahead of
the southeastward advancing cold front by late afternoon. Aided by
forcing for ascent supported by low-level warm advection beneath
broadly difluent upper flow, activity may consolidate into one or
two eastward/southeastward propagating clusters by Saturday evening.

...Northern Mid Atlantic into Champlain Valley...
A corridor of moderate to large developing mixed-layer CAPE, ahead
of the southeastward advancing cold front, and within preceding
deepening surface troughing, seems likely to provide the focus for
vigorous thunderstorm development by late Saturday afternoon.
Although lapse rates may be modest, and stronger potential
instability across the northern Mid Atlantic may be displaced to the
south of the better flow/shear across Upstate New York into New
England, the environment may still become conducive to scattered
strong thunderstorms accompanied by a risk for potentially damaging
wind gusts. If/when lingering uncertainties become more clear, it
is possible that severe probabilities could still be increased a bit
further in later outlooks for this period.

..Kerr.. 06/26/2025

$$

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ACUS03 KWNS 270726
SWODY3
SPC AC 270725

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0225 AM CDT Fri Jun 27 2025

Valid 291200Z - 301200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR FAR SOUTHEAST
MINNESOTA INTO THE WESTERN UPPER PENINSULA OF MICHIGAN....

...SUMMARY...
Isolated to scattered strong to severe storms are possible from the
central High Plains to the northern Great Lakes on Sunday.

...Synopsis...
A mid-level trough will amplify across the northern Plains on
Sunday. At the surface, a cold front will move across the Upper
Midwest to near northern Lower Michigan to the central Plains by 12Z
Monday.

...Central Plains to the Upper Midwest...
Very strong to extreme instability is forecast to develop ahead of a
cold front from the central Plains to Wisconsin. Storms are expected
to develop along this front during the afternoon to evening on
Sunday. Shear will be mostly weak along the front which may limit
storm organization. However, where stronger mid-level flow is
present (central and northern Wisconsin into the western UP of
Michigan), more organized storms are expected, including the
potential for supercells. These storms will pose a threat for severe
wind gusts and large hail, and perhaps a tornado.

Farther south and west along the front, weaker shear will be
present. However, very strong heating and steep lapse rates will
support some severe wind threat as storms develop along the uncapped
front during the afternoon/evening on Sunday.

..Bentley.. 06/27/2025

$$

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ACUS03 KWNS 271931
SWODY3
SPC AC 271930

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Fri Jun 27 2025

Valid 291200Z - 301200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SUNDAY ACROSS
PARTS OF THE UPPER MIDWEST...

...SUMMARY...
Scattered strong to severe storms appear possible Sunday from the
central Great Plains into the upper Great Lakes region, with at
least some potential for the evolution of a large, organized severe
storm cluster across parts of the mid into lower Missouri Valley and
central Great Plains late Sunday through Sunday night.

...Discussion...
Stronger westerlies will remain confined to the northern
mid-latitudes, but models indicate further amplification of flow
across the northeastern Pacific into interior North America through
this period. This is forecast to include building mid/upper ridging
across British Columbia through the western Canadian Prairies and
northern U.S. Rockies, and digging downstream troughing across the international border toward the Upper Midwest. As mid-level flow
transitions from westerly to northwesterly across the northern
Rockies toward the middle/lower Missouri Valley, an initially
prominent plume of warm elevated mixed-layer air advecting to the
east of the Rockies is likely to become increasingly suppressed southward/southwestward into and through the central Great Plains by
early Monday. Although the main surface cold front may only reach
the Upper Midwest into high plains to the south of the Black Hills,
this may be preceded by a notable wind shift, reinforced by
considerable convective outflow through much of the central Great
Plains into middle Mississippi Valley.

...Central Great Plains into middle/lower Missouri Valley...
There is a notable signal within the model output that a large
reservoir of moderate to strong potential instability, beneath the
plume of warm elevated mixed-layer air, may provide support for one
or two significant upscale growing clusters of thunderstorms Sunday
through Sunday night. There remains sizable spread among the
various output concerning where, ranging from near/east of the mid
into lower Missouri Valley to portions of western Nebraska into
Kansas. Much may depend on the evolution of a possible evolving
cluster of storms, and its outflow, across southern South
Dakota/northern Nebraska Saturday night, and the extent of the
suppression of the elevated mixed-layer by early Sunday, which
remain unclear.

Stronger instability may tend to become displaced to the south of
the stronger westerlies, but modest shear due to veering winds with
height, coupled the thermodynamic profiles, characterized by
unsaturated lower/mid-levels, with steep lapse rates and large CAPE,
seem likely to become supportive of organized convection with strong
cold pools capable of producing swaths of strong to severe surface
gusts.

Severe probabilities will probably need to be upgraded once
lingering uncertainties become better resolved.

...Upper Midwest...
If early period convection does not impact subsequent
destabilization near/ahead of the southeastward advancing frontal
zone, it still appears possible that deep-layer shear and forcing
for ascent downstream of the digging short wave trough could support
scattered strong to severe storm development in a corridor across
southwestern through northeastern Wisconsin and portions of adjacent
states.

..Kerr.. 06/27/2025

$$

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ACUS03 KWNS 280724
SWODY3
SPC AC 280723

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0223 AM CDT Sat Jun 28 2025

Valid 301200Z - 011200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE OHIO VALLEY AND MID-ATLANTIC...

...SUMMARY...
Scattered strong to severe thunderstorms are possible across parts
of the Ohio Valley and the Mid-Atlantic on Monday.

...Synopsis...
A mid-level trough will amplify as it moves through the western
Great Lakes on Monday. Meanwhile, mid-level ridging will remain
persistent across the western CONUS. At the surface, a cold front
will move across the southern Great Lakes and Ohio Valley. High
pressure will build into the Plains in the wake of this cold front.

...Ohio Valley...
Moderate instability is forecast to develop ahead of the cold front
in the Ohio Valley on Monday with dewpoints in the low 70s and
temperatures warming to near 80. Mid-level flow around 25 to 30
knots may provide sufficient shear for some multicell clusters with
a threat for damaging wind gusts Monday afternoon/evening. This
threat should be mostly diurnally driven and wane after dark.

...Mid-Atlantic...
Moderate instability is forecast east of the Appalachians on Monday
as temperatures warm into the low to mid 90s with dewpoints in the
mid to upper 60s. Shear will be quite weak, but steep low-level
lapse rates will support some threat for damaging wind gusts.

..Bentley.. 06/28/2025

$$

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ACUS03 KWNS 281929
SWODY3
SPC AC 281928

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 PM CDT Sat Jun 28 2025

Valid 301200Z - 011200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE OHIO VALLEY...MIDWEST...AND MID-ATLANTIC...

...SUMMARY...
Scattered strong to severe thunderstorms are possible across parts
of the Ohio Valley, Midwest and the Mid-Atlantic on Monday.

...Synopsis...
An amplifying midlevel trough and accompanying jet streak will
advance eastward across the Midwest and Great Lakes on Monday. At
the same time, a related cold front will overspread the OH Valley
through the afternoon.

...Ohio Valley and Midwest...
Widely scattered thunderstorms are expected along/ahead of the
eastward-moving cold front in the OH Valley, aided by large-scale
ascent preceding the midlevel trough. While midlevel lapse rates
will be modest over the warm sector, diurnal heating of a moist air
mass (lower 70s dewpoints) will still contribute to moderate-strong surface-based buoyancy (highest over the lower OH Valley). Around 30
kt of deep-layer shear and the destabilizing air mass will favor
organized multicell clusters capable of producing wind damage
through the afternoon.

Farther west, large-scale ascent in the left-exit region of the
midlevel jet will promote isolated thunderstorms across the Midwest
during the afternoon. Sufficient post-frontal moisture beneath steep
midlevel lapse rates, and elongated/straight hodographs (30-40 kt of
deep-layer shear), will support isolated severe hail in the stronger
cells.

...Mid-Atlantic...
Despite weak deep-layer flow/shear, a few wet microbursts will be
possible east of the Appalachians during the afternoon, where steep
low-level lapse rates will develop amid deep/rich tropospheric
moisture (PW around 2 inches).

..Weinman.. 06/28/2025

$$

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ACUS03 KWNS 290723
SWODY3
SPC AC 290722

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0222 AM CDT Sun Jun 29 2025

Valid 011200Z - 021200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE
CAROLINAS INTO THE NORTHEAST...

...SUMMARY...
Isolated to scattered strong to severe storms are possible from the
Carolinas to the Northeast on Tuesday afternoon/evening.

...Synopsis...
A mid-level trough will shift east from the Great Lakes to the
Northeast on Tuesday. Moderate mid-level flow will overspread much
of the Great Lakes and Northeast. At the surface, a cold front will
move east across the Northeast and arc back into the southern
Plains. This front will be the primary focus for severe thunderstorm
potential on Tuesday.

...Carolinas to the Northeast...
Low to mid 70s dewpoints should be in place ahead of the cold front
east of the Appalachians on Tuesday. Diurnal destabilization should
result in weak to moderate instability from the Carolinas into the
Northeast by early afternoon. The greatest instability is expected
across North Carolina and Virginia. Storm coverage will likely be
higher in this area, but with limited deep-layer shear, storms will
likely be less organized.

Farther north, stronger shear will be present from Pennsylvania
northward. This may result in greater storms organization including
the potential for a few supercells with a threat for large hail and
damaging wind gusts. Mid-level lapse rates will be weak (<6 C/km)
which will be the primary limiting factor to greater severe weather probabilities across portions of the Northeast.

..Bentley.. 06/29/2025

$$

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ACUS03 KWNS 291927
SWODY3
SPC AC 291926

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0226 PM CDT Sun Jun 29 2025

Valid 011200Z - 021200Z

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

...SUMMARY...
Scattered strong to severe storms are possible across parts of the
Mid-Atlantic into the Northeast on Tuesday afternoon/evening. An
isolated severe storm may also occur over parts of the central High
Plains.

...Synopsis...
A mid-level trough will track across the Northeast as upper-ridging
remains in place across the central CONUS, and an upper low meanders
along the West Coast on Tuesday. At the surface, a cold front will
sweep across the Northeast/Mid-Atlantic regions while a surface
anticyclone overspreads much of the U.S. between the Rockies and
Appalachians. Ahead of the surface cold front, ample moisture and
instability, coinciding with modest deep-layer shear, will support
scattered strong thunderstorms, a few of which may be severe.

...Northeast into the Mid-Atlantic...
As the surface cold front advances east across the central/northern Appalachians, surface heating should support surface temperatures
rising into the 80s to 90 F amid low to mid 70s F dewpoints,
resulting in moderate buoyancy. The rich low-level moisture,
overspread by mediocre lapse rates, will support 2500+ J/kg MLCAPE,
constrained to tall/thin profiles. With the approach of the trough,
enough strengthening with height of the 850-500 mb wind fields will
encourage 25-40 kts of effective bulk shear and the subsequent
development of multicells and short line segments. At least isolated
damaging gusts are possible throughout the Northeast. However, a
Category 2/Slight risk was added across parts of the Mid-Atlantic,
where the latest guidance depicts relatively robust convective
development, and where forecast buoyancy is strongest. Here, wind
damage may occur on a more frequent basis.

...Central High Plains...
Weak upslope low-level flow around the aforementioned surface
anticyclone will encourage the northwestward advection of upper 50s
to 60 F surface dewpoints into the Nebraska Panhandle and immediate
adjacent areas by Tuesday afternoon. These dewpoints will be
overspread by 7.5-8.5 C/km mid-level lapse rates, resulting in at
least 1500 J/kg MLCAPE. Isolated thunderstorms are expected to
develop off of the higher terrain as they progress eastward.
Multicellular or perhaps transient supercellular storm modes are
possible given lackluster vertical wind shear. Nonetheless, a stray
severe thunderstorm is possible, accompanied by mainly a severe
wind/hail threat.

..Squitieri.. 06/29/2025

$$

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ACUS03 KWNS 300729
SWODY3
SPC AC 300728

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 AM CDT Mon Jun 30 2025

Valid 021200Z - 031200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Widespread scattered storms are possible across a large portion of
the CONUS on Wednesday. Organized severe storms appear unlikely, but
isolated damaging wind gusts may be possible from the Southeast to
the Carolinas.

...Discussion...
Widespread monsoon thunderstorms are expected across a large portion
of the Southwest into the central Rockies. Additional widespread
thunderstorm activity is expected along and south of a cold front
which extends from the central/southern Plains across the Southeast
and into the Carolinas. Shear will be very weak across this entire
zone with very poor mid-level lapse rates. However, moisture will be
very high with PWAT values around 1.75" to 2" across the Southeast.
Therefore, isolated stronger storms are possible with a threat for
wet microbursts. However, a lack of a more focused zone of threat
within a broad, low probability risk area, precludes severe weather probabilities at this time.

Moderate instability is forecast across the northern Plains on
Wednesday. However, the mid-level ridge is forecast to strengthen
during the period which should keep thunderstorm activity mostly
limited. As the nocturnal low-level jet strengthens on Wednesday
night, some thunderstorms are possible across portions of the
northern Plains. However, these storms will likely remain sub-severe
given relatively limited elevated instability.

Stronger mid-level flow will be present west of the mid-level ridge
across Montana and to its east across the Great Lakes on Wednesday.
However, limited moisture will lead to mostly weak instability in
both areas. Therefore, storm coverage/intensity remains
questionable.

..Bentley.. 06/30/2025

$$

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ACUS03 KWNS 301922
SWODY3
SPC AC 301921

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0221 PM CDT Mon Jun 30 2025

Valid 021200Z - 031200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE NORTHERN ROCKIES...

...SUMMARY...
At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. A couple of severe gusts may
accompany the stronger storms over portions of the Northern Rockies.

...Synopsis...
A mid-level trough will meander across the Northeast while upper
ridging persists over the central CONUS and a mid-level trough
advances over the Pacific Northwest on Wednesday. Seasonal moisture
and associated diurnal heating will encourage at least scattered
development across most of the CONUS during the afternoon and
evening hours. However, a couple of thunderstorms embedded in the
stronger mid-level flow over the Northern Rockies could become
strong. Given adequate shear and instability in this region, a few
of the stronger storms could become severe.

...Portions of the Northern Rockies...
The periphery of relatively greater mid-level moisture is poised to
traverse the western extent of the upper ridge on Wednesday.
Stronger west-southwesterly mid-level flow will graze the Northern
Rockies due to the approach of the upper trough to the west. Robust
boundary layer heating in this region will boost low-level lapse
rates to 9 C/km over several locales, as 8.5 C/km mid-level lapse
rates overspreads the well-mixed boundary layer. MLCAPE may exceed
1000 J/kg over many areas, and thunderstorms accessing this buoyancy
will be embedded in stronger mid-level flow and 30-40 kts of
effective bulk shear. As such, stronger multicells may produce a mix
of wet and dry downbursts, perhaps inducing a couple of severe
gusts.

..Squitieri.. 06/30/2025

$$

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ACUS03 KWNS 010729
SWODY3
SPC AC 010728

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 AM CDT Tue Jul 01 2025

Valid 031200Z - 041200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE
NORTHEAST AND THE NORTHERN PLAINS...

...SUMMARY...
Scattered storms capable of large hail and severe wind gusts are
forecast across the Northeast on Thursday. Isolated severe wind
gusts are also possible in the northern Plains.

...Synopsis...
A mid-level ridge will shift east across the central CONUS with a
strong and amplifying trough across the Northeast. To the west of
the ridge axis, moderate southwesterly flow is forecast from the
Northwest into the northern Rockies with multiple embedded shortwave
troughs. At the surface, a cold front will move quickly east across
the Northeast during the afternoon/evening on Thursday. In addition,
a lee cyclone will develop across the western Dakotas. A warm front
will extend east from this low pressure center and a dryline/surface
trough extending to its south.

...Northeast...
Moderate instability is forecast to develop on Thursday afternoon
ahead of a cold front across the Northeast. Cooling mid-level
temperatures, associated with the deepening mid-level trough, will
steepen lapse rates through the day. In addition, a moderately
strong mid-level jet streak will overspread the warm sector with 40
to 50 knots of mid-level flow. A more concentrated severe weather
threat may occur beneath this mid-level jet streak if moderate
instability can develop where shear would be maximized.

...Northern Plains...
Moderate to strong instability is forecast to develop north of the
surface low across the western Dakotas. Weak isentropic ascent and
height falls in an uncapped environment may support some strong
storms Thursday afternoon/evening across far eastern Montana into
the western Dakotas. The primary limiting factor to a greater severe
weather threat will be shear with only 20 to 25 knots forecast.
However, this may be sufficient for a few multicell clusters capable
of isolated severe wind gusts.

..Bentley.. 07/01/2025

$$

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