917  
ACUS02 KWNS 131636  
SWODY2  
SPC AC 131634  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1034 AM CST THU NOV 13 2025  
 
VALID 141200Z - 151200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST
 
 
   
..SUMMARY
 
 
THE RISK FOR THUNDERSTORMS APPEARS NEGLIGIBLE ACROSS THE U.S. FRIDAY  
THROUGH FRIDAY NIGHT.  
   
..DISCUSSION
 
 
A MORE PROMINENT BLOCKING REGIME CENTERED ACROSS THE NORTHERN  
ATLANTIC CONTINUES TO EVOLVE. MODELS INDICATE THAT THIS WILL  
INCLUDE THE DEVELOPMENT OF A BROAD CYCLONIC REGIME CENTERED ACROSS  
THE CANADIAN MARITIMES BY EARLY FRIDAY, WHICH WILL PERSIST THROUGH  
THE REMAINDER OF THE PERIOD. SOME AMPLIFICATION OF LARGE-SCALE  
TROUGHING EXTENDING SOUTHWARD OFFSHORE OF THE REMAINDER OF THE  
ATLANTIC SEABOARD IS FORECAST, DOWNSTREAM OF A SIGNIFICANT MID-LEVEL  
TROUGH AND EMBEDDED CYCLONE MIGRATING NORTHEAST AND EAST OF THE  
CANADIAN MARITIMES, ON THE LEADING EDGE OF A MORE PROGRESSIVE  
REGIME.  
 
UPSTREAM, BROAD SHORT WAVE RIDGING APPEARS LIKELY TO SHIFT INLAND OF  
THE BRITISH COLUMBIA COAST, ACROSS AND EAST OF THE CANADIAN/NORTHERN  
U.S. ROCKIES, TO THE NORTH OF AN INCREASINGLY CUT-OFF LOW OFFSHORE  
OF THE CENTRAL AND SOUTHERN CALIFORNIA COAST.  
 
MODELS CONTINUE TO INDICATE THAT THE MODIFYING MID-LEVEL COLD CORE  
OF THE EASTERN PACIFIC LOW (INCLUDING COLDEST 500 MB TEMPERATURES  
WARMING ABOVE -24 C) WILL GENERALLY REMAIN OFFSHORE THROUGH THIS  
PERIOD. WHILE IT MAY TEND TO PIVOT AWAY FROM COASTAL AREAS  
NEAR/SOUTH OF SAN FRANCISCO BAY, AND SLOWLY TOWARD SOUTHERN  
CALIFORNIA COASTAL AREAS FRIDAY NIGHT, THE LEADING EDGE OF STRONGER  
FORCING FOR ASCENT/COOLING ALOFT SUPPORTIVE OF LOW-TOPPED  
THUNDERSTORM DEVELOPMENT APPEARS LIKELY TO REMAIN WELL WEST OF THE  
SOUTHERN CALIFORNIA COASTAL WATERS THROUGH 12Z SATURDAY.  
 
POTENTIAL FOR THUNDERSTORM DEVELOPMENT FRIDAY THROUGH FRIDAY NIGHT  
APPEARS LARGELY CONFINED TO A PLUME OF LOWER LATITUDE EASTERN  
PACIFIC MOISTURE RETURN, ADVECTING AHEAD OF THE LOW INTO THE  
SOUTHERN PERIPHERY OF THE STRONGER MID-LATITUDE WESTERLIES. MODELS  
SUGGEST THAT THIS MAY CONTRIBUTE TO DEVELOPING LAYERS OF WEAK  
CONDITIONAL INSTABILITY ROOTED IN THE LOWER/MID-TROPOSPHERIC, ACROSS  
THE SOUTHERN CALIFORNIA COAST THROUGH PORTIONS OF THE SOUTHERN  
SIERRA NEVADA AND MOJAVE DESERT, GREAT BASIN, NORTHERN ROCKIES, AND  
NORTHERN GREAT PLAINS. WEAK CONVECTION BECOMING BRIEFLY CAPABLE OF  
PRODUCING A FEW LIGHTNING STRIKES MAY NOT BE ENTIRELY OUT OF THE  
QUESTION ANYWHERE WITHIN THIS CORRIDOR. HOWEVER, DUE TO LIKELY  
SPARSE COVERAGE AND RATHER LOW PREDICTABILITY, PROBABILITIES FOR  
THUNDERSTORMS STILL APPEAR GENERALLY LESS THAN 10 PERCENT.  
 
..KERR.. 11/13/2025  
 

 
 
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