331  
ACUS11 KWNS 040709  
SWOMCD  
SPC MCD 040708  
WIZ000-040845-  
 
MESOSCALE DISCUSSION 2230  
NWS STORM PREDICTION CENTER NORMAN OK  
0208 AM CDT FRI SEP 04 2026  
 
AREAS AFFECTED...PORTIONS OF EASTERN WISCONSIN  
 
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY  
 
VALID 040708Z - 040845Z  
 
PROBABILITY OF WATCH ISSUANCE...20 PERCENT  
 
SUMMARY...A CLUSTER OF SUPERCELLS WILL LIKELY PERSIST FOR ANOTHER  
COUPLE OF HOURS BEFORE MOVING OFFSHORE. SEVERE GUSTS AND SOME HAIL  
ARE POSSIBLE.  
 
DISCUSSION...AS OF 0705 UTC, LOCAL RADAR IMAGERY SHOWED A CLUSTER OF  
STRONG TO SEVERE STORMS ONGOING FROM EAST-CENTRAL WI TOWARD THE LAKE  
MICHIGAN COAST. AIDED BY LOW-LEVEL WARM ADVECTION AT THE TERMINUS OF  
A SOUTHWESTERLY LOW-LEVEL JET, THESE STORMS ARE LIKELY ELEVATED,  
BEING SUPPORTED BY 2000-3000 J/KG OF MUCAPE. THE LARGE BUOYANCY AND  
40-50 KT OF NORTHWESTERLY DEEP-LAYER SHEAR WILL LIKELY MAINTAIN  
STORM ORGANIZATION/INTENSITY FOR A FEW HOURS BEFORE CONVECTION MOVES  
OVER THE LAKE.  
 
VARIABLE STORM MODE HAS BEEN NOTED WITH BOTH SUPERCELLS AND SOME  
CLUSTERING EVIDENT. THE STRONGEST CLUSTER (WINNEBAGO AND WAUSHARA  
COUNTIES) HAS SHOWN SOME INCREASE IN FORWARD SPEED ALONG WITH  
UPSCALE GROWTH. GRADUAL COALESCENCE SHOULD CONTINUE AS NEW UPDRAFTS  
HAVE BEEN OBSERVE DEVELOPING ALONG OUTFLOW AND NEAR THE LAKE SHORE  
WHICH MAY BE AIDING IN LOCALIZED CONVERGENCE. THIS SUGGESTS SOME  
INCREASE IN DAMAGING/SEVERE GUSTS MAY OCCUR. EXACTLY HOW MUCH RISK  
DEVELOPS IS UNCLEAR GIVEN THAT THE BOUNDARY LAYER IS STABLE (TEMPS  
IN THE 60S TO 70S F) AND THESE STORMS REMAIN ELEVATED. STILL, SOME  
SEVERE GUSTS ARE POSSIBLE, ALONG WITH A RISK FOR HAIL GIVEN THE  
LARGE BUOYANCY AND SUPERCELLS. CURRENT EXPECTATIONS ARE FOR THE  
SEVERE RISK TO REMAIN ISOLATED ENOUGH THAT A WATCH LIKELY WONT BE  
NEEDED. HOWEVER, CONVECTIVE TRENDS WILL BE MONITORED IF A MORE  
ORGANIZED/PERSISTENT SEVERE RISK BECOMES APPARENT.  
 
..LYONS/MOSIER.. 09/04/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...GRB...MKX...  
 
LAT...LON 42998842 43428887 43598904 43788926 43998933 44168934  
44408884 44468830 44308784 44188771 43888769 43778775  
43518777 43158778 43008781 42908791 42918825 42998842  
 
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
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