177  
ACUS01 KWNS 121630  
SWODY1  
SPC AC 121628  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1128 AM CDT TUE AUG 12 2025  
 
VALID 121630Z - 131200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF  
THE GREAT LAKES AND SOUTHEAST ARIZONA INTO SOUTHWEST NEW MEXICO...  
   
..SUMMARY  
 
STRONG TO LOCALLY SEVERE THUNDERSTORMS ARE POSSIBLE OVER PARTS OF  
THE GREAT LAKES/MIDWEST THIS AFTERNOON WITH BOTH DAMAGING WINDS AND  
HAIL POSSIBLE. GUSTY WINDS MAY ALSO OCCUR OVER SOUTHEAST ARIZONA  
AND SOUTHWEST NEW MEXICO.  
   
..GREAT LAKES/MIDWEST  
 
MIDDAY SATELLITE/RADAR COMPOSITE SHOW A WEAKENED THUNDERSTORM BAND  
MOVING EAST-NORTHEAST ACROSS THE EASTERN PART OF LOWER MI. SURFACE  
ANALYSIS INDICATES RAIN-COOLED AIR NORTH OF A GUST FRONT/OUTFLOW  
THAT HAS BECOME DRAPED FROM SOUTHEAST LOWER MI INTO THE MICHIANA  
REGION. HEATING SOUTH OF THIS BOUNDARY HAS RESULTED IN TEMPERATURES  
WARMING THROUGH THE MID-UPPER 80S WITH DEWPOINTS IN THE LOWER 70S.  
ADDITIONAL STORMS WILL PROBABLY DEVELOP ALONG THE TRAILING OUTFLOW  
AND GRADUALLY MOVE EAST-NORTHEAST WITH THE MEAN WIND. CONSIDERABLY  
WEAKER DEEP-LAYER SHEAR IS PRESENT ACROSS THE EASTERN PART OF THE  
CORN BELT INTO THE LOWER MI VICINITY COMPARED TO FARTHER NORTH OVER  
THE U.P. OF MI IN CLOSER PROXIMITY TO A SHORTWAVE TROUGH.  
NONETHELESS, SCATTERED THUNDERSTORMS WILL GRADUALLY DEVELOP WITHIN A  
MOIST/DESTABILIZING AIRMASS AND POSE A RISK FOR ISOLATED STRONG TO  
PERHAPS LOCALLY SEVERE/DAMAGING GUSTS THIS AFTERNOON.  
 
FARTHER NORTH IN WI INTO THE U.P. OF MI, A WEAK COLD FRONT WILL MOVE  
INTO THE REGION LATER THIS AFTERNOON. MODEL GUIDANCE SHOWS WIDELY  
SCATTERED STORMS DEVELOPING AS FILTERED SUNSHINE LEADS TO A  
DESTABILIZING BOUNDARY LAYER. A FEW STRONGER THUNDERSTORMS ARE  
POSSIBLE AND COULD YIELD A LOCALIZED RISK FOR MARGINALLY SEVERE HAIL  
AND DAMAGING GUSTS DURING THE MID AFTERNOON TO EARLY EVENING PERIOD.  
   
..SOUTHEAST AZ/SOUTHWEST NM  
 
STRONG HEATING SHOULD RESULT IN WIDELY SCATTERED THUNDERSTORMS  
DEVELOPING NEAR TERRAIN-FAVORED AREAS. WEAK SHEAR WILL RESULT IN  
DISORGANIZED STORMS, BUT THE DEVELOPMENT OF VERY STEEP SURFACE TO  
500-MB LAPSE RATES WILL PROMOTE STRONG EVAPORATIVE COOLING WITH THE  
MORE INTENSE DOWNDRAFTS. ISOLATED SEVERE GUSTS ARE POSSIBLE.  
 
..SMITH/SQUITIERI.. 08/12/2025  
 
 
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