ACUS11 KWNS 192030
SWOMCD
SPC MCD 192030
NEZ000-SDZ000-192230-

Mesoscale Discussion 1661
NWS Storm Prediction Center Norman OK
0330 PM CDT Sun Jul 19 2026

Areas affected...portions of the Black Hills into south-central
South Dakota and northern Nebraska

Concerning...Severe potential...Watch unlikely

Valid 192030Z - 192230Z

Probability of Watch Issuance...20 percent

SUMMARY...Some potential for damaging/severe wind gusts may
accompany developing, high-based convection through this evening.

DISCUSSION...Latest visible satellite imagery depicts a field of
towering cumulus with recent lightning activity across portions of
southwestern South Dakota. Modifying the nearby 18z UNR observed
sounding for nearby observations depicts a deep, well-mixed boundary
layer with steep low-level lapse rates, 500 to 750 J/kg MLCAPE, and
LCLs around 3 km AGL. This thermodynamic environment will support
high-based convection, with some potential for isolated
damaging/severe wind gusts likely to evolve through the
afternoon/evening given surface dewpoint depressions of 40-50 F.

Latest high-res guidance suggests that some clustering of convection
along developing cold pools may occur over the next several hours;
however, uncertainty remains regarding the longevity of this
convection. With this activity occurring along the southern
periphery of stronger mid-to-upper level flow, effective shear is
limited to around 20-25 kts per latest mesoanalysis. This lends some
credence to a more limited severe risk compared to areas farther
north. Thus, watch issuance appears unlikely at this time but could
be considered should a longer duration risk for damaging/severe wind
gusts evolve through this afternoon and evening.

..Chalmers/Thompson.. 07/19/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fjg!7QmsGG_6fE8EExPepmsmRcK4-Ril_0zgPtKi1BxEn_poKG_h17NNLxbLc9V6NateCarHxl6jhe9YrxZZrj5SRlRax-M$ for graphic product...

ATTN...WFO...ABR...LBF...UNR...CYS...

LAT...LON 44230018 44089971 43789949 43479954 42930000 42500075
42180211 42120294 42120338 42340366 42760371 43340341
43860270 44210192 44310147 44340124 44230018

MOST PROBABLE PEAK WIND GUST...55-70 MPH


= = =
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.
--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)