408  
ACUS48 KWNS 020848  
SWOD48  
SPC AC 020847  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0347 AM CDT THU OCT 02 2025  
 
VALID 051200Z - 101200Z  
   
..DISCUSSION
 
 
MEDIUM-RANGE GUIDANCE INDICATES THAT BLOCKING WITHIN THE WESTERLIES  
ACROSS THE MID-LATITUDE EASTERN PACIFIC WILL REMAIN PROMINENT INTO  
THE MIDDLE TO LATTER PORTION OF NEXT WEEK. HOWEVER, ONE MID-LEVEL  
HIGH FORMING OFF THE PACIFIC COAST THIS WEEKEND MAY BE RELATIVELY  
SHORT-LIVED, AND SUBSEQUENT DEVELOPMENTS OFF THE PACIFIC INTO NORTH  
AMERICA REMAIN UNCLEAR, BASED ON RATHER LARGE SPREAD APPARENT IN THE  
MODEL OUTPUT.  
 
EARLY IN THE PERIOD, A STILL NOTABLE, BUT PERHAPS WEAKENING,  
MID-LEVEL SHORT WAVE PERTURBATION, AND ASSOCIATED COMPACT SURFACE  
CYCLONE, MAY QUICKLY MIGRATE FROM THE EASTERN DAKOTAS THROUGH  
NORTHWESTERN ONTARIO DURING THE DAY SUNDAY. IN THE PRESENCE OF  
SEASONABLY STRONG AND SHEARED LOWER/MID-TROPOSPHERIC WIND FIELDS,  
THERE APPEARS AT LEAST SOME POTENTIAL FOR RENEWED STRONG TO SEVERE  
THUNDERSTORM DEVELOPMENT, MAINLY ACROSS PARTS OF NORTH CENTRAL  
MINNESOTA THROUGH THE WESTERN LAKE SUPERIOR VICINITY BY SUNDAY  
EVENING. HOWEVER, MOSTLY DUE TO A CONTINUING LACK OF BETTER  
LOW-LEVEL MOISTURE RETURN, POTENTIAL FOR DESTABILIZATION SUPPORTIVE  
OF MORE THAN A RELATIVELY ISOLATED/MARGINAL SEVERE RISK STILL SEEMS  
LOW OR AT LEAST UNCERTAIN.  
 
ELSEWHERE, THERE APPEARS AT LEAST SOME SIGNAL FOR INCREASING  
CONVECTIVE POTENTIAL AHEAD OF AN AMPLIFYING SHORT WAVE TROUGH AND  
ASSOCIATED COLD FRONT ADVANCING SOUTHEAST OF THE LOWER GREAT LAKES  
REGION, WHICH COULD IMPACT THE NORTHEASTERN URBAN CORRIDOR BY LATE  
WEDNESDAY. AT THIS POINT, THIS APPEARS MOST NOTABLE IN ECMWF/ECENS  
RELATED OUTPUT, COMPARED TO OTHER MODEL OUTPUT, AT A PERIOD OF  
INCREASING MODEL SPREAD AND LOW PREDICTABILITY.  
 
..KERR.. 10/02/2025  
 
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