164  
ACUS48 KWNS 120837  
SWOD48  
SPC AC 120835  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0335 AM CDT WED AUG 12 2026  
 
VALID 151200Z - 201200Z  
   
..DISCUSSION
 
   
..D4/SATURDAY
 
 
MOST GUIDANCE DEPICTS ONE OR MORE MIDLEVEL VORTICITY MAXIMA CRESTING  
THE UPPER RIDGE AND MOVING ACROSS THE UPPER MIDWEST/GREAT LAKES  
REGION ON SATURDAY. HOWEVER, THERE IS CONSIDERABLE SPREAD REGARDING  
THE TIMING OF THESE FEATURES AND THE NORTHWARD EXTENT OF SUBSTANTIAL  
DESTABILIZATION. THE GENERAL PATTERN SUGGESTS SOME POTENTIAL FOR MCS  
DEVELOPMENT ACROSS PARTS OF THE MIDWEST/GREAT LAKES REGION, BUT  
UNCERTAINTY REGARDING THE FAVORED CORRIDOR PRECLUDES ADDITION OF 15%  
PROBABILITIES AT THIS TIME.  
   
..D5/SUNDAY
 
 
EXTENDED-RANGE GUIDANCE IS IN GENERAL AGREEMENT DEPICTING A COLD  
FRONT THAT WILL MOVE ACROSS PARTS OF THE MIDWEST, GREAT LAKES, OHIO  
VALLEY, AND NORTHEAST ON SUNDAY. THIS FRONT WILL IMPINGE UPON A  
RESERVOIR OF RICH MOISTURE AND MODERATE TO LOCALLY STRONG BUOYANCY,  
WHICH COULD RESULT IN A SEVERE-THUNDERSTORM THREAT ALONG/AHEAD OF  
THE FRONT. SUBSTANTIAL TIMING DIFFERENCES REMAIN REGARDING THE  
FRONT, BUT SEVERE PROBABILITIES MAY EVENTUALLY BE NEEDED FOR THIS  
SCENARIO.  
   
..D6/MONDAY - D7/TUESDAY
 
 
A SIMILAR UPPER-LEVEL PATTERN IS EXPECTED TO PERSIST INTO EARLY NEXT  
WEEK, WITH WEST-NORTHWESTERLY MIDLEVEL FLOW EXTENDING FROM THE  
NORTHERN PLAINS INTO THE MIDWEST/GREAT LAKES AND  
NORTHEAST/MID-ATLANTIC. THIS PATTERN WILL CONTINUE TO FAVOR AT LEAST  
AN ISOLATED SEVERE THREAT, WITH LOW-PREDICTABILITY MCS POTENTIAL.  
 
..DEAN.. 08/12/2026  
 
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