843  
ACUS11 KWNS 112257  
SWOMCD  
SPC MCD 112257  
ILZ000-WIZ000-120100-  
 
MESOSCALE DISCUSSION 1648  
NWS STORM PREDICTION CENTER NORMAN OK  
0557 PM CDT FRI JUL 11 2025  
 
AREAS AFFECTED...SOUTHERN WISCONSIN AND NORTHERN ILLINOIS  
 
CONCERNING...TORNADO WATCH 505...508...  
 
VALID 112257Z - 120100Z  
 
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 505, 508 CONTINUES.  
 
SUMMARY...AN ORGANIZED CLUSTER OF STORMS LIKELY WILL CONTINUE TO  
POSE A RISK FOR STRONG TO SEVERE SURFACE GUSTS, AND PERHAPS AN  
ADDITIONAL BRIEF TORNADO OR TWO, ACROSS SOUTHERN WISCONSIN AND  
NORTHERN ILLINOIS DURING THE NEXT COUPLE OF HOURS, REACHING THE  
GREATER MILWAUKEE INTO PORTIONS OF THE GREATER CHICAGO METRO AREAS  
BY 8 PM CDT.  
 
DISCUSSION...THE EVOLVING CONVECTIVE SYSTEM HAS BECOME BETTER  
ORGANIZED OVER THE PAST COUPLE OF HOURS, WITH AT LEAST ONE  
DEVELOPING MESO-BETA SCALE CYCLONIC VORTEX (NOW NEAR DUBUQUE IA)  
BECOMING INCREASINGLY PROMINENT. THE APEX OF THE SOUTHWARD TRAILING  
BOW ECHO STRUCTURE IN RADAR REFLECTIVITIES IS PROPAGATING  
EAST-NORTHEASTWARD AROUND 45 KT, AND, AT THIS CONTINUED MOTION, WILL  
REACH THE SOUTHWESTERN SHORES OF LAKE MICHIGAN NEAR THE GREATER  
MILWAUKEE AREA BY 01Z.  
 
IN THE PRESENCE OF 20-30 KT WEST-SOUTHWESTERLY MEAN AMBIENT FLOW,  
MODERATELY STRONG EASTERLY UPDRAFT INFLOW OF SEASONABLY MOIST AIR  
CHARACTERIZED BY CAPE IN EXCESS OF 1500 J/KG SEEMS LIKELY TO  
MAINTAIN CURRENT CONVECTIVE INTENSITIES AT LEAST TO THE THE  
SOUTHWESTERN SHORES OF LAKE MICHIGAN. AS LONG AS THIS CONTINUES,  
WESTERLY REAR INFLOW PROBABLY WILL REMAIN SUFFICIENTLY STRONG TO  
CONTRIBUTE TO STRONG TO SEVERE SURFACE GUSTS IN DOWNDRAFTS.  
 
..KERR.. 07/11/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...LOT...MKX...DVN...  
 
LAT...LON 43208980 43548869 43568796 43178750 42218756 41788778  
41678926 41768977 42488951 42969002 43208980  
 
MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH  
MOST PROBABLE PEAK WIND GUST...65-80 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
 
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