830  
ACUS11 KWNS 301535  
SWOMCD  
SPC MCD 301534  
MIZ000-WIZ000-301730-  
 
MESOSCALE DISCUSSION 1395  
NWS STORM PREDICTION CENTER NORMAN OK  
1034 AM CDT TUE JUN 30 2026  
 
AREAS AFFECTED...NORTHEAST WISCONSIN TO NORTHWEST LOWER MICHIGAN  
 
CONCERNING...SEVERE THUNDERSTORM WATCH 422...  
 
VALID 301534Z - 301730Z  
 
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 422  
CONTINUES.  
 
SUMMARY...ISOLATED OCCURRENCES OF LARGE HAIL AND LOCALLY DAMAGING  
WIND GUSTS REMAIN POSSIBLE ACROSS MAINLY THE SOUTHERN HALF OF SEVERE  
THUNDERSTORM WATCH 422. SOME REMNANT OF THE ONGOING STORMS COULD  
MOVE INTO PARTS OF NORTHWEST LOWER MICHIGAN BY EARLY AFTERNOON AND  
POSE A SEVERE WEATHER THREAT.  
 
DISCUSSION...TRENDS IN VISIBLE SATELLITE AND RADAR DATA INDICATE  
PERIODIC INTENSIFICATION-WEAKENING CYCLES WITH THE STORMS ONGOING  
WEST THROUGH SOUTHWEST OF GREEN BAY. THE STORMS ARE MOVING THROUGH A  
MOIST AND MODERATE TO STRONGLY UNSTABLE ENVIRONMENT WITH MLCAPE AS  
HIGH AS 3000-3500 J/KG, PER LATEST OBJECTIVE ANALYSIS. THE STORM  
BEHAVIOR THUS FAR SUGGESTS THEY MAY STILL BE SLIGHTLY ELEVATED AND  
ARE NOT FULLY REALIZING THE AVAILABLE BUOYANCY. THE CURRENT KGRB VWP  
IS SAMPLING LARGELY WESTERLY TROPOSPHERIC WINDS WITH 40-50 KT SPEEDS  
NOTED ABOVE 5-6 KM.  
 
THE ENVIRONMENT DESCRIBED ABOVE IS SUPPORTIVE OF STORM ORGANIZATION,  
ASSUMING UPDRAFTS CAN BECOME ROOTED IN THE BOUNDARY LAYER. LARGE  
HAIL IS THE PRIMARY CONCERN IN THE SHORT TERM, BUT THE POTENTIAL FOR  
DAMAGING WINDS MAY INCREASE WITH TIME OWING TO THE UNIDIRECTIONAL  
WIND PROFILES AND POTENTIAL FOR DOWNSHEAR PROPAGATION ALONG AN  
ORGANIZING COLD POOL.  
 
SOME CONVECTION-ALLOWING MODEL GUIDANCE INDICATES THE WI STORMS  
MOVING ACROSS LAKE MI INTO NORTHWEST LOWER MI BY EARLY AFTERNOON  
WITH AN ASSOCIATED DAMAGING WIND THREAT. HOWEVER, CONSIDERABLE  
CLOUDINESS CURRENTLY EXISTS ACROSS LOWER MI THIS MORNING, WHICH IS  
SLOWING THE DESTABILIZATION PROCESS.  
 
..MEAD.. 06/30/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...APX...GRR...MQT...GRB...MKX...  
 
LAT...LON 44468939 45128908 45138734 44958580 44268563 43868626  
43878785 44108872 44228909 44468939  
 
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
 
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