696  
ACUS48 KWNS 050746  
SWOD48  
SPC AC 050744  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0244 AM CDT SAT SEP 05 2026  
 
VALID 081200Z - 131200Z  
   
..DISCUSSION  
 
...DAYS 4-6/TUE-THU -- CENTRAL PLAINS TO GREAT LAKES/OHIO VALLEY AND  
MID-ATLANTIC...  
 
AN UPPER SHORTWAVE TROUGH WILL SHIFT EAST ACROSS THE UPPER  
MIDWEST/GREAT LAKES AND NORTHEAST THROUGH THURSDAY. AN ASSOCIATED  
SURFACE LOW WILL MAINLY REMAIN OVER CANADA, BUT A TRAILING COLD  
FRONT WILL SWEEP ACROSS PARTS OF THE CENTRAL PLAINS AND UPPER  
MIDWEST ON TUESDAY, BEFORE CONTINUING SOUTH AND EAST INTO KANSAS AND  
ACROSS THE GREAT LAKES ON WEDNESDAY. BY THURSDAY, THE BOUNDARY IS  
EXPECTED TO CONTINUE SOUTH AND EAST ACROSS THE OHIO VALLEY AND  
MID-ATLANTIC. STRONGER LARGE-SCALE ASCENT WILL LIKELY REMAIN FOCUSED  
NEAR AND NORTH OF THE INTERNATIONAL BORDER. FURTHERMORE, THE  
CORRIDOR OF DEEPER BOUNDARY LAYER MOISTURE MAY BE SOMEWHAT LIMITED,  
ESPECIALLY TUESDAY INTO WEDNESDAY, DUE TO A PRIOR COLD FRONTAL  
PASSAGE AND SURFACE HIGH PRESSURE OVER THE MIDWEST. NEVERTHELESS,  
ENHANCED DEEP-LAYER FLOW, AND CORRIDORS OF AT LEAST MODEST  
INSTABILITY ALONG THE COLD FRONT COULD SUPPORT SOME SEVERE RISK.  
HOWEVER, CONFIDENCE IN 15 PERCENT OR GREATER COVERAGE IS LOW AT THIS  
TIME FRAME.  
   
..DAYS 7-8/FRI-SAT -- NORTHERN/CENTRAL PLAINS TO UPPER MIDWEST  
 
AT THE END OF THE PERIOD, ANOTHER UPPER SHORTWAVE TROUGH MAY DIG  
SOUTHEAST FROM THE PACIFIC NORTHWEST AND INTO THE PLAINS. ANOTHER,  
PERHAPS STRONGER, COLD FRONT COULD SWEEP ACROSS THE PLAINS AND THE  
MID/UPPER MS VALLEY. DEPENDING ON MOISTURE RETURN IN THE WAKE OF THE  
EARLIER COLD FRONTAL PASSAGE, SOME SEVERE RISK COULD DEVELOP DURING  
THE WEEKEND. FURTHERMORE, LARGE SPREAD EXISTS AMONG VARIOUS GUIDANCE  
REGARDING THE EVOLUTION OF THE THIS UPPER TROUGH, RESULTING IN  
UNCERTAINTY IN GREATER CORRIDORS OF SEVERE POTENTIAL.  
 
..LEITMAN.. 09/05/2026  
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