872  
ACUS11 KWNS 090140  
SWOMCD  
SPC MCD 090139  
WIZ000-MNZ000-SDZ000-090345-  
 
MESOSCALE DISCUSSION 1905  
NWS STORM PREDICTION CENTER NORMAN OK  
0839 PM CDT FRI AUG 08 2025  
 
AREAS AFFECTED...EASTERN SOUTH DAKOTA INTO CENTRAL MINNESOTA AND  
NORTHWEST WISCONSIN  
 
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY  
 
VALID 090139Z - 090345Z  
 
PROBABILITY OF WATCH ISSUANCE...80 PERCENT  
 
SUMMARY...THUNDERSTORM DEVELOPMENT IS ANTICIPATED ACROSS EASTERN  
SOUTH DAKOTA INTO SOUTHWEST MINNESOTA IN THE COMING HOURS. THESE  
STORMS WILL QUICKLY INTENSIFY AND POSE A THREAT FOR LARGE HAIL AND  
SEVERE GUSTS DOWNSTREAM INTO CENTRAL MINNESOTA AND EVENTUALLY  
NORTHWEST WISCONSIN LATER TONIGHT. WATCH ISSUANCE IS EXPECTED.  
 
DISCUSSION...RECENT GOES IR IMAGERY SHOWS THE EARLY STAGES OF  
DEEPENING UPDRAFTS ALONG A COLD FRONT TO THE NORTH/NORTHWEST OF THE  
SIOUX FALLS, SD AREA AND SOUTH OF ALEXANDRIA, MN. BASED ON 00Z  
SOUNDINGS FROM ABR AND OAX, THIS PORTION OF THE FRONT APPEARS TO  
HAVE SUFFICIENTLY WEAK MLCIN TO ALLOW FOR CONVECTIVE DEVELOPMENT,  
WHICH HAS BEEN ANTICIPATED BY AFTERNOON/EARLY-EVENING CAM GUIDANCE  
DURING THE 02-04 UTC PERIOD. AS SUCH, CONFIDENCE IS SOMEWHAT HIGH  
THAT THIS IS THE BEGINNING OF TONIGHT'S MORE APPRECIABLE SEVERE  
THREAT ACROSS THE UPPER MS VALLEY. REGIONAL 00Z SOUNDINGS ALSO  
SAMPLED STEEP-MID-LEVEL LAPSE RATES SUPPORTING EXTREME MLCAPE VALUES  
ON THE ORDER OF 4000-4500 J/KG. WHILE DEEP-LAYER SHEAR WITHIN THE  
OPEN WARM SECTOR IS SOMEWHAT WEAK (AROUND 15-20 PER THE MPX  
SOUNDING), NORTHERLY POST-FRONTAL WINDS ARE ELONGATING HODOGRAPHS  
WITHIN THE FRONTAL ZONE AND SHOULD PROMOTE ORGANIZED CONVECTION  
SHORTLY AFTER SUSTAINED/DEEP INITIATION. WHILE A FEW INITIAL  
SUPERCELLS ARE POSSIBLE (WITH AN ATTENDANT THREAT FOR LARGE HAIL),  
UPSCALE GROWTH IS EXPECTED THROUGH THE LATE EVENING HOURS ACROSS  
CENTRAL/NORTHEAST MN AND NORTHWEST WI WITH AN INCREASING RISK FOR  
SEVERE WINDS AND PERHAPS BRIEF LINE-EMBEDDED TORNADOES - WITHIN THE  
WARM SECTOR WHERE 0-1 KM SRH IS ON THE ORDER OF AROUND 100-150  
M2/S2. WATCH ISSUANCE IS EXPECTED TO ADDRESS THIS POTENTIAL.  
 
..MOORE/GUYER.. 08/09/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...DLH...MPX...FGF...FSD...ABR...  
 
LAT...LON 43869705 44319706 47079521 47499494 47799439 47929371  
47929306 47869233 47619162 47459127 47169104 46779089  
46289098 46019102 45699132 45439147 45089192 43669537  
43539585 43519631 43589672 43869705  
 
MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH  
MOST PROBABLE PEAK WIND GUST...65-80 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN  
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