335  
ACUS48 KWNS 080726  
SWOD48  
SPC AC 080724  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0224 AM CDT TUE SEP 08 2026  
 
VALID 111200Z - 161200Z  
   
..DISCUSSION
 
   
..DAYS 4-5/FRI-SAT -- PLAINS TO THE GREAT LAKES VICINITY
 
 
SEVERE POTENTIAL COULD DEVELOP ACROSS PORTIONS OF THE PLAINS INTO  
THE UPPER MIDWEST ON DAY 4/FRIDAY AS BOUNDARY LAYER MOISTURE SPREADS  
NORTHWARD AHEAD OF A SOUTHEASTWARD-ADVANCING COLD FRONT. MODERATE TO  
STRONG DESTABILIZATION AHEAD OF THE FRONT, AND ENHANCED VERTICAL  
SHEAR COURTESY OF A MODEST UPPER SHORTWAVE TROUGH MOVING ACROSS THE  
NORTHERN PLAINS/UPPER MIDWEST VICINITY, SHOULD BE SUFFICIENT FOR  
ORGANIZED CONVECTION MAINLY FROM FRIDAY EVENING INTO EARLY SATURDAY.  
 
SOME SEVERE POTENTIAL COULD PERSIST INTO DAY 5 SATURDAY AS THE  
SURFACE FRONT STALLS OVER THE CENTRAL/SOUTHERN PLAINS VICINITY BUT  
CONTINUES EASTWARD ACROSS THE UPPER GREAT LAKES REGION. A MOIST  
BOUNDARY LAYER WILL BE IN PLACE, BUT STRONGER FLOW ALOFT WILL BECOME  
INCREASING DISPLACED TO THE NORTH OF STRONGER INSTABILITY,  
PRECLUDING 15 PERCENT DELINEATION AT THIS TIME.  
   
..DAYS 6-8/SUN-TUE
 
 
AN UPPER TROUGH OVER THE NORTHWESTERN U.S. WILL DEVELOP EASTWARD  
ACROSS THE PLAINS AND GREAT LAKES EARLY NEXT WEEK. ANOTHER COLD  
FRONT WILL MOVE ACROSS THE AREA, AND SOME SEVERE POTENTIAL COULD  
AGAIN SWEEP ACROSS THE PLAINS TO THE UPPER MIDWEST/GREAT LAKES  
VICINITY. MEDIUM RANGE FORECAST GUIDANCE GENERALLY MAINTAINS  
STRONGER INSTABILITY OFFSET FROM ENHANCED FLOW ALOFT, PARTLY DUE TO  
THE EARLY COLD FRONTAL PASSAGE IN THE DAY 4-5/FRIDAY-SATURDAY TIME  
FRAME AND STRONG SURFACE HIGH PRESSURE OVER THE GREAT LAKES IN THE  
WAKE OF THAT FRONTAL PASSAGE. TRENDS WILL BE MONITORED AND  
PROBABILITIES COULD BECOME NECESSARY IN LATER OUTLOOKS.  
 
..LEITMAN.. 09/08/2026  
 
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