ACUS11 KWNS 201849

SWOMCD

SPC MCD 201849 

KSZ000-NEZ000-COZ000-202115-



Mesoscale Discussion 2316

NWS Storm Prediction Center Norman OK

0149 PM CDT Sun Sep 20 2026



Areas affected...northeast/eastern Colorado...far western Kansas and

southwest Nebraska



Concerning...Severe potential...Watch possible 



Valid 201849Z - 202115Z



Probability of Watch Issuance...60 percent



SUMMARY...At least isolated storms are likely to develop over

northeast Colorado, with large hail probable. A few severe gusts

could occur by early evening.



DISCUSSION...A prominent vorticity max aloft is moving across WY,

with southern lobe and cooling aloft spreading across northern CO.

Visible imagery shows towering CU and initial convection over the

Palmer Divide, and over far northeast CO south of a wind shift

related to ongoing weak thunderstorms.



Continued heating along with a gradual veering of surface winds will

lead to further destabilization. Given cool temperatures

aloft/steepening lapse rates, mid 50s F dewpoints and effective

deep-layer shear over 40 kt, a supercell or two may occur. Max hail

size over 2.00" may be possible as cells generally track

southeastward toward western KS by early evening. Left splitting

cells may also produce hail into southwest NE. Damaging wind gusts

also appear possible if more of a cluster or aggregating outflows

develop.



..Jewell/Mosier.. 09/20/2026



...Please see www.spc.noaa.gov for graphic product...



ATTN...WFO...LBF...GLD...PUB...BOU...



LAT...LON   40220334 40460298 40730285 40840268 40980228 41000202

            40900172 40610145 39830141 38920139 38430141 38290190

            38350236 38430280 38750360 39090405 39400426 39640424

            39860407 40220334 



MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH

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

MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN