516  
ACUS11 KWNS 172257  
SWOMCD  
SPC MCD 172256  
MNZ000-IAZ000-180100-  
 
MESOSCALE DISCUSSION 0461  
NWS STORM PREDICTION CENTER NORMAN OK  
0556 PM CDT THU APR 17 2025  
 
AREAS AFFECTED...SOUTHEAST MINNESOTA INTO NORTHWEST IOWA  
 
CONCERNING...SEVERE THUNDERSTORM WATCH 140...  
 
VALID 172256Z - 180100Z  
 
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 140  
CONTINUES.  
 
SUMMARY...STORMS IN SOUTHEAST MINNESOTA WILL POSE A SHORT-TERM  
THREAT FOR SMALL TO MARGINALLY SEVERE HAIL AND PERHAPS ISOLATED WIND  
DAMAGE. ADDITIONAL DEVELOPMENT, THOUGH NOT CERTAIN, IS POSSIBLE IN  
NORTHWEST IOWA. LARGE HAIL AND DAMAGING WINDS WOULD BE THE MAIN  
THREAT IN THAT AREA.  
 
DISCUSSION...A LINE OF STORMS SOUTH OF THE TWIN CITIES WILL CONTINUE  
EASTWARD. THIS LINE HAS SHOWN A WEAKENING TREND OVER THE LAST HOUR  
AS IT HAS ENCOUNTERED COOLER/DRIER AIR. ISOLATED WIND DAMAGE AND  
SMALL TO MARGINALLY SEVER HAIL COULD OCCUR WITH THIS ACTIVITY, BUT A  
CONTINUED DOWNWARD TREND IN INTENSITY IS EXPECTED.  
 
A SMALL ZONE OF GREATER SURFACE HEATING AHEAD OF THE COLD FRONT IS  
SITUATED IN NORTHWEST IOWA. AS AN UPSTREAM SHORTWAVE PERTURBATION  
MOVES TOWARDS THE AREA THIS EVENING, MODESTLY INCREASING FRONTAL  
CONVERGENCE AND MID-LEVEL ASCENT COULD PROMOTE AN ADDITIONAL STORM  
OR TWO WITHIN THIS ZONE. SHOULD STORMS FORM HERE, STEEP MID-LEVEL  
LAPSE RATES AND 40 KTS OF EFFECTIVE SHEAR WILL SUPPORT LARGE HAIL  
AND DAMAGING WIND POTENTIAL.  
 
..WENDT.. 04/17/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...ARX...MPX...DMX...FSD...  
 
LAT...LON 42299536 42279594 42319622 42489614 42889588 43759492  
44189462 44449410 44539336 44269239 43779237 42819424  
42399481 42299536  
 
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
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