342  
ACUS11 KWNS 182230  
SWOMCD  
SPC MCD 182229  
WIZ000-ILZ000-IAZ000-190030-  
 
MESOSCALE DISCUSSION 2029  
NWS STORM PREDICTION CENTER NORMAN OK  
0529 PM CDT TUE AUG 18 2026  
 
AREAS AFFECTED...NORTHEAST IOWA...SOUTHERN WISCONSIN...NORTHERN  
ILLINOIS  
 
CONCERNING...SEVERE THUNDERSTORM WATCH 595...  
 
VALID 182229Z - 190030Z  
 
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 595  
CONTINUES.  
 
SUMMARY...SEVERE THREAT CONTINUES WITHIN WW595.  
 
DISCUSSION...THUNDERSTORMS ACROSS SOUTHERN WISCONSIN HAVE TAKEN ON A  
MORE LINEAR/BOWING MODE OVER THE LAST HOUR. THE LINE HAS PRODUCED A  
FEW INSTANCES OF DAMAGING WIND, WITH MEASURED GUSTS UP TO 61 MPH.  
DEEP LAYER FLOW IS LARGELY WESTERLY, WHICH WILL LIKELY PUSH THE LINE  
EASTWARD ACROSS SOUTHERN WISCONSIN THROUGH THE EVENING WITH DAMAGING  
WIND BECOMING THE MAIN THREAT.  
 
WATCH ISSUANCE FURTHER SOUTH OF WW595 REMAINS UNCERTAIN. DEEP LAYER  
FLOW DECREASES FURTHER SOUTH, WITH MID-LEVEL CLOUD COVER IN PLACE  
AND LESS INSTABILITY. ADDITIONALLY, LAPSE RATE PROFILES ARE MEAGER.  
A COUPLE OF CELLS HAVE DEVELOPED FURTHER WEST ACROSS FAR EASTERN  
IOWA. THESE MAY POSE SOME POTENTIAL FOR LARGE HAIL IN THE SHORT  
TERM. IT REMAINS UNCERTAIN THAT COVERAGE/DURATION WILL WARRANT  
ADDITIONAL WATCH ISSUANCE AT THIS TIME BUT THIS AREA WILL BE  
MONITORED.  
 
..THORNTON.. 08/18/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...GRB...LOT...MKX...DVN...ARX...  
 
LAT...LON 43269158 43409092 43629034 43948929 43858813 43738786  
43448767 43188765 42868775 42328788 42148831 41988888  
41958956 42079019 42289090 42469136 42679166 42819174  
43269158  
 
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
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