148  
ACUS01 KWNS 151232  
SWODY1  
SPC AC 151230  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0630 AM CST SAT NOV 15 2025  
 
VALID 151300Z - 161200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE OHIO VALLEY...  
   
..SUMMARY  
 
SHOWERS AND ISOLATED THUNDERSTORMS MAY BE ACCOMPANIED BY STRONG WIND  
GUSTS ACROSS PARTS OF THE UPPER OHIO VALLEY LATE THIS AFTERNOON AND  
EVENING.  
   
..OHIO VALLEY  
 
LARGE-SCALE ASCENT WILL SPREAD ACROSS THE OH VALLEY TODAY AHEAD OF A  
MID-LEVEL SHORTWAVE TROUGH THAT WILL DIG ACROSS THE GREAT LAKES BY  
THIS EVENING. AN ASSOCIATED SURFACE LOW WILL DEVELOP EASTWARD ACROSS  
SOUTHERN ONTARIO, WITH A COLD FRONT EXTENDING SOUTHWARD ACROSS THE  
OH VALLEY/MIDWEST. THIS FRONT WILL SERVE AS THE PRIMARY FOCUS FOR  
ISOLATED THUNDERSTORMS THIS AFTERNOON AND EVENING. ONLY MODEST  
DAYTIME HEATING IS FORECAST AHEAD OF THE FRONT, WHICH COMBINED WITH  
LIMITED LOW-LEVEL MOISTURE SHOULD TEMPER THE AMOUNT OF SURFACE-BASED  
INSTABILITY THAT CAN DEVELOP. EVEN SO, A STRONGLY SHEARED  
ENVIRONMENT IS EXPECTED GIVEN THE STRENGTH OF THE LOW/MID-LEVEL FLOW  
FORECAST. RECENT HIGH-RESOLUTION GUIDANCE SUGGESTS WEAK FRONTAL  
CONVECTION SHOULD DEVELOP BY LATE AFTERNOON/EARLY EVENING ACROSS  
EASTERN OH/WESTERN PA AND VICINITY. STRONG TO LOCALLY DAMAGING WIND  
GUSTS ARE THE PRIMARY CONCERN, WITH CONVECTION EXPECTED TO WEAKEN  
WITH EASTWARD EXTENT INTO CENTRAL PA THIS EVENING DUE TO MEAGER  
INSTABILITY WITH THE LOSS OF DAYTIME HEATING.  
   
..SOUTHERN CALIFORNIA/SOUTHWEST  
 
A STRONG (60-80 KT) 500 MB SPEED MAXIMUM WILL TRANSLATE THROUGH THE  
BASE OF AN UPPER TROUGH AND DEVELOP TOWARDS THE NORTHERN BAJA  
PENINSULA BY MIDDAY, WITH HIGH-LEVEL DIFFLUENT FLOW FORECAST ACROSS  
SOUTHERN CA AND THE LOWER CO RIVER VALLEY. RECENT GUIDANCE CONTINUES  
TO SUGGEST AN ASSOCIATED SURFACE FRONT WILL MOVE INLAND LATER TODAY,  
AND COOLING POST-FRONTAL THERMAL PROFILES ALOFT WILL LEAD TO WEAK  
INSTABILITY THAT SHOULD FAVOR OCCASIONAL LIGHTNING WITHIN DEEPER  
CONVECTIVE UPDRAFTS. PRE-FRONTAL CONVECTION IS EXPECTED TO BE ONLY  
WEAKLY BUOYANT ACROSS THE LOWER CO RIVER VALLEY DUE TO POOR LAPSE  
RATES, WHICH SHOULD LIMIT UPDRAFT STRENGTH. WHILE POST-FRONTAL  
DESTABILIZATION MAY LEAD TO MORE ROBUST UPDRAFTS, WEAKER SHEAR IN  
THIS REGIME DOES NOT APPEAR FAVORABLE FOR SEVERE WINDS, BUT SMALL  
HAIL COULD OCCUR.  
 
..GLEASON/BROYLES.. 11/15/2025  
 
 
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