031  
ACUS11 KWNS 122151  
SWOMCD  
SPC MCD 122151  
MIZ000-WIZ000-122345-  
 
MESOSCALE DISCUSSION 1936  
NWS STORM PREDICTION CENTER NORMAN OK  
0451 PM CDT TUE AUG 12 2025  
 
AREAS AFFECTED...EASTERN WISCONSIN INTO THE UPPER PENINSULA OF  
MICHIGAN  
 
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY  
 
VALID 122151Z - 122345Z  
 
PROBABILITY OF WATCH ISSUANCE...5 PERCENT  
 
SUMMARY...ISOLATED THUNDERSTORMS DEVELOPING ACROSS EASTERN WISCONSIN  
INTO THE UPPER PENINSULA OF LOWER MICHIGAN MAY INTENSIFY THROUGH  
EARLY EVENING AND POSE RISK FOR LARGE HAIL AND/OR DAMAGING WINDS.  
HOWEVER, THIS THREAT SHOULD REMAIN TOO LIMITED FOR WATCH ISSUANCE.  
 
DISCUSSION...CONVECTION CONTINUES TO PERCOLATE ALONG A DIFFUSE  
FRONTAL ZONE FROM THE U.P. OF LOWER MICHIGAN INTO CENTRAL WI. AT  
LEAST ONE MATURING CELL ACROSS THE U.P. APPEARS TO BE DEVELOPING A  
MID-LEVEL MESOCYCLONE, WHICH IS INDICATIVE OF STRONG SHEAR  
(ESTIMATED TO BE AROUND 30-35 KNOTS OF EFFECTIVE BWD) OVER THE  
REGION AND ADEQUATE BUOYANCY FOR DEEP CONVECTION. DEVELOPING CELLS  
TO THE SOUTHWEST ALONG THE FRONT ARE ALSO SHOWING SOME SIGNS OF  
DEEPER DEVELOPMENT/INTENSIFICATION, THOUGH THIS HAS BEEN A SLOW  
PROCESS OVER THE PAST HOUR. THE SLUGGISH GROWTH DURING PEAK HEATING  
IS LIKELY DUE TO SOMEWHAT WEAK LOW-LEVEL ASCENT ALONG THE FRONT, AS  
SUGGESTED BY ONLY A MODEST SURFACE WIND SHIFT AND A DIFFUSE  
CROSS-FRONTAL TEMPERATURE GRADIENT ACROSS WI. WITH THE ONSET OF  
NOCTURNAL COOLING COMING IN A FEW HOURS AND WITH THE  
FRONT/CONVECTION MOVING TOWARDS THE LAKE MICHIGAN SHORE, THE SPATIAL  
AND TEMPORAL WINDOW FOR AN APPRECIABLE SEVERE THREAT MAY BE LIMITED.  
NONETHELESS, THE THERMODYNAMIC AND KINEMATIC ENVIRONMENT ACROSS THE  
REGION WILL REMAIN FAVORABLE FOR ORGANIZED STORMS, INCLUDING A  
SUPERCELL OR TWO, FOR THE NEXT FEW HOURS WITH AN ATTENDANT THREAT  
FOR SEVERE HAIL AND DAMAGING WINDS.  
 
..MOORE/HART.. 08/12/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...APX...MQT...GRB...MKX...ARX...  
 
LAT...LON 43318785 43218814 43218856 43278906 43388945 43778968  
44098973 44348966 44658913 45058867 45748795 46348710  
46498668 46628627 46678585 46748535 46748507 46678481  
46558461 46348448 46138444 45818473 45778497 45858517  
45898550 45848599 45758622 45568650 45248677 44948706  
44718720 44378738 43938752 43688759 43318785  
 
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH  
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN  
 
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