601  
ACUS02 KWNS 140533  
SWODY2  
SPC AC 140532  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1132 PM CST THU NOV 13 2025  
 
VALID 151200Z - 161200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER  
OHIO VALLEY...  
   
..SUMMARY  
 
SHOWERS AND A FEW THUNDERSTORMS MAY BE ACCOMPANIED BY STRONG WIND  
GUSTS ACROSS PARTS OF THE UPPER OHIO VALLEY SATURDAY EVENING.  
   
..UPPER OHIO VALLEY  
 
AN UPPER RIDGE OVER FROM ONTARIO/QUEBEC INTO THE OHIO VALLEY WILL  
BREAK DOWN/SHIFT EAST ACROSS THE NORTHEAST THROUGH SATURDAY EVENING  
AS A DEEPENING SHORTWAVE TROUGH MOVES ACROSS THE GREAT LAKES AND  
MIDWEST. AT THIS OCCURS, A DEEPENING SURFACE LOW WILL PIVOT EASTWARD  
ACROSS SOUTHERN ONTARIO AND INTO NEW ENGLAND BY EARLY SUNDAY  
MORNING. A TRAILING COLD FRONT WILL DEVELOP SOUTHWARD ACROSS THE  
LOWER GREAT LAKES/OHIO VALLEY AND NORTHEAST DURING THE NIGHTTIME  
HOURS. AHEAD OF THIS FEATURE, SOUTHERLY LOW-LEVEL FLOW WILL  
TRANSPORT MODEST BOUNDARY-LAYER MOISTURE NORTHWARD, WITH SURFACE  
DEWPOINTS EXPECTED TO MAINLY BE IN THE 50S F.  
 
FORECAST SOUNDINGS INDICATED MEAGER INSTABILITY MAY DEVELOP (LESS  
THAN 500 J/KG) WITH COOLER TEMPERATURES ALOFT IN THE 700-500 MB  
LAYER. THE LOWER TROPOSPHERE THERMODYNAMIC PROFILES ARE SOMEWHAT  
LACKLUSTER, WITH WARMER 850-700 MB TEMPERATURES NOTED IN BOTH RAP  
AND NAM SOUNDINGS, RESULTING IN POOR LAPSE RATES. NEVERTHELESS,  
STRENGTHENING WESTERLY FLOW IN THE LOWEST 3 KM TO AROUND 40-50 KT  
AMID MEAGER INSTABILITY COULD RESULT IN ISOLATED STRONG GUSTS FOR A  
FEW HOURS DURING THE EVENING BEFORE CONVECTION WEAKENS WITH EASTWARD  
EXTENT INTO THE OVERNIGHT HOURS.  
   
..COASTAL SOUTHERN CA  
 
AN UPPER LOW OFFSHORE THE SOUTHERN CA COAST WILL MOVE INLAND ON  
SATURDAY. AT THE SURFACE, A WEAK LOW AND ASSOCIATED WIND SHIFT WILL  
MOVE INLAND IN THE 12-18Z TIME PERIOD. FORECAST SOUNDINGS INDICATE  
VERY MEAGER SURFACE-BASED INSTABILITY WILL BE PRESENT. CURRENTLY,  
FORECAST GUIDANCE VARIES CONSIDERABLY, WITH RAP FORECAST SOUNDINGS  
SHOWING VIRTUALLY NO SURFACE-BASED INSTABILITY COMPARED TO NAM  
FORECAST SOUNDINGS SHOWING 100-300 J/KG SBCAPE, WITH HRRR FORECAST  
SOUNDINGS SOMEWHERE IN BETWEEN. NEVERTHELESS, 30-40 KT FLOW IN THE  
1-3 KM LAYER COULD RESULT IN LOCALLY GUSTY WINDS, ESPECIALLY IN  
HIGHER ELEVATIONS THROUGH MIDDAY, WITH LOW-TOPPED CONVECTIVE  
ELEMENTS.  
 
..LEITMAN.. 11/14/2025  
 
 
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