ACUS11 KWNS 300325
SWOMCD
SPC MCD 300325=20
NEZ000-SDZ000-300530-

Mesoscale Discussion 1391
NWS Storm Prediction Center Norman OK
1025 PM CDT Mon Jun 29 2026

Areas affected...portions of central and northeastern Nebraska

Concerning...Severe Thunderstorm Watch 418...

Valid 300325Z - 300530Z

The severe weather threat for Severe Thunderstorm Watch 418
continues.

SUMMARY...The potential for severe wind gusts (potentially including significant gusts up to 75-90 mph) and large hail is expected to
expand northeastward over the next 1-2 hours.

DISCUSSION...Ongoing convection across Severe Thunderstorm Watch 218
has been slow to develop/organize thus far, but an uptick in
convective intensity has recently been noted across central Nebraska
over the past 30-60 minutes. This activity is occurring along the
northern periphery of a surface instability/theta-e gradient and at
the northern tip of a strengthening southerly, low-level jet sampled
by the UEX VWP. While latest high-res model guidance has somewhat
struggled with the overall placement of convection, guidance
continues to suggest that upscale growth into a compact, bowing
cluster/complex will occur as convection evolves (and potentially
accelerates northeastward) along the aforementioned gradient.=20

While uncertainty remains regarding the exact convective evolution
over the next 1-2 hours owing to the complexity of cell/convective interactions, strong to extreme instability (MLCAPE of 4000-5000
J/kg indicated by latest objective analysis and the 00z OAX observed
sounding) along and southeast of this gradient coupled with strong
effective shear (50-60+ kts) and steep mid-level lapse rates would
favor an increasing severe threat in this scenario. Severe to
significant wind gusts up to 75-90 mph (perhaps locally greater in a
higher-end scenario) remain conditionally plausible pending the
organization of ongoing convection into an organized cluster. Large
hail also remains possible with any semi-discrete or embedded
supercell structures, with additional potential for wind-driven hail
to accompany any stronger cluster.

..Chalmers.. 06/30/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!7K6gSGateY9HYYgoNopLSjFovJIWBB4B8RuhcAWrl1VYrh4XX1Qtx0A0qd9HFV-pi8VQxA1Fv= Xd6EZRdpwykAMkncUg$ for graphic product...

ATTN...WFO...FSD...OAX...GID...LBF...

LAT...LON 41239886 41269914 41409943 41659942 41939927 42389866
42649826 42769802 42889768 42919723 42779671 42579656
42309649 42089666 41899692 41629743 41389811 41239886=20

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...75-90 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN


=3D =3D =3D
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* Origin: Capitol City Weather Station (1:2320/127)