256  
ACUS11 KWNS 091421  
SWOMCD  
SPC MCD 091420  
WIZ000-ILZ000-091545-  
 
MESOSCALE DISCUSSION 1877  
NWS STORM PREDICTION CENTER NORMAN OK  
0920 AM CDT SUN AUG 09 2026  
 
AREAS AFFECTED...PORTIONS OF SOUTHERN WISCONSIN INTO FAR NORTHERN  
ILLINOIS  
 
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE  
 
VALID 091420Z - 091545Z  
 
PROBABILITY OF WATCH ISSUANCE...40 PERCENT  
 
SUMMARY...AN ORGANIZED BOWING STRUCTURE, LIKELY ELEVATED AT PRESENT  
TIME, COULD BECOME NEAR SURFACE BASED AS IT MOVES INTO SOUTHEASTERN  
WISCONSIN AND ADJACENT NORTHERN ILLINOIS. WIND DAMAGE WOULD BE THE  
MAIN THREAT. A WATCH IS POSSIBLE SHOULD OBSERVATIONAL TRENDS  
WARRANT.  
 
DISCUSSION...A SMALL BOWING CLUSTER HAS BEEN MOVING SOUTHEASTWARD  
THIS MORNING. THIS ACTIVITY HAS REMAINED ELEVATED THUS FAR, BUT THE  
AIRMASS AHEAD OF IT IS SLOWLY DESTABILIZING. DEWPOINTS IN NORTHERN  
ILLINOIS/SOUTHERN WISCONSIN HAVE INCREASED OVER THE PAST COUPLE OF  
HOURS. THE MAIN LIMITER IN TERMS OF DESTABILIZATION HAS BEEN THE  
CLOUD COVER/SMOKE THAT HAS REDUCED INSOLATION. BASED ON FORECAST  
SOUNDINGS, IF TEMPERATURES CAN REACH THE MID 70S F THE STORMS WILL  
BE AT LEAST NEAR SURFACE BASED. GIVEN THE CURRENT ORGANIZATION OF  
ONGOING CONVECTION, THERE MAY BE AN INCREASE IN DAMAGING WIND  
POTENTIAL OVER THE NEXT COUPLE OF HOURS. THE NEED FOR A WATCH IS  
UNCERTAIN AND WILL DEPEND ON OBSERVATION TRENDS.  
 
..WENDT/HART.. 08/09/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...LOT...MKX...ARX...  
 
LAT...LON 42338865 42578899 43008959 43609043 43968955 43808901  
43158779 42748767 42538767 42418772 42278830 42338865  
 
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH  
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH  
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN  
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