625  
ACUS11 KWNS 202232  
SWOMCD  
SPC MCD 202231  
WIZ000-MNZ000-IAZ000-SDZ000-210030-  
 
MESOSCALE DISCUSSION 2056  
NWS STORM PREDICTION CENTER NORMAN OK  
0531 PM CDT THU AUG 20 2026  
 
AREAS AFFECTED...PORTIONS OF CENTRAL INTO SOUTHWESTERN MINNESOTA AND  
FAR EASTERN SOUTH DAKOTA  
 
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE  
 
VALID 202231Z - 210030Z  
 
PROBABILITY OF WATCH ISSUANCE...60 PERCENT  
 
SUMMARY...THE RISK FOR SEVERE HAIL WILL INCREASE THROUGH THE EVENING  
HOURS AS STORMS GRADUALLY DEVELOP THROUGH THE EVENING. A FEW SEVERE  
GUSTS AND A TORNADO OR TWO MAY ALSO OCCUR. TIMING OF STORM  
DEVELOPMENT IS UNCERTAIN, BUT CONVECTIVE TRENDS WILL BE CLOSELY  
MONITORED FOR THE NEED OF A WW ISSUANCE.  
 
DISCUSSION...A FEW DISCRETE STORMS HAVE DEVELOPED AND SUSTAINED  
THEMSELVES ALONG A SURFACE TROUGH OVER NORTHERN MN, WHERE MRMS MESH  
DEPICTS SOME HAIL POTENTIALLY FALLING WITH THESE STORMS. AS THE  
SURFACE TROUGH CONTINUES TO MOVE SOUTHEAST, STORMS SHOULD GRADUALLY  
INCREASE IN COVERAGE AND INTENSITY, ESPECIALLY AFTER 0Z. SURFACE  
TEMPERATURES APPROACHING 80 F, AMID MID 60S F DEWPOINTS AND 7-8 C/KM  
BOUNDARY-LAYER LAPSE RATES, IS YIELDING OVER 2000 J/KG MLCAPE.  
FURTHERMORE, INCREASED SOUTHWESTERLY 850 MB FLOW BENEATH MODEST 500  
MB WESTERLIES IS CONTRIBUTING TO 40 KTS OF EFFECTIVE BULK SHEAR,  
ESPECIALLY OVER CENTRAL AND SOUTHERN MN. CURRENTLY, THE MPX VAD  
SHOWS A MODESTLY CURVED AND ELONGATED HODOGRAPH, SUPPORTIVE OF  
SUPERCELL STRUCTURES. THE CURRENT THINKING IS THAT ANY STORM THAT  
CAN MATURE AND SUSTAIN ITSELF IN THIS ENVIRONMENT WILL BECOME  
SUPERCELLULAR, ACCOMPANIED BY A SEVERE HAIL THREAT (SOME POTENTIALLY  
EXCEEDING 2 INCHES IN DIAMETER). A FEW SEVERE GUSTS MAY ALSO OCCUR,  
AND GIVEN THE APPRECIABLE LOW-LEVEL HODOGRAPH, A TORNADO OR TWO  
CANNOT BE RULE OUT EITHER.  
 
VISIBLE SATELLITE SHOWS AN OVERALL LACK OF AGITATED CU, WITH SEVERAL  
BILLOW CLOUDS REMAINING (INDICATIVE OF SOME RESIDUAL STABILITY). IT  
IS THUS UNCLEAR WHEN CONVECTIVE INITIATION AND THE SUBSEQUENT NEED  
FOR A WW ISSUANCE WILL OCCUR. GIVEN THE FAVORABLE AMBIENT  
ENVIRONMENT THOUGH, CONVECTIVE TRENDS WILL BE CLOSELY MONITORED.  
 
..SQUITIERI/GUYER.. 08/20/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...DLH...MPX...FGF...FSD...ABR...  
 
LAT...LON 43719738 45259588 46249498 46669442 46899402 46919341  
46689310 46059276 45309267 44639294 44129357 43669477  
43429560 43389667 43719738  
 
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  
 
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