680  
ACUS48 KWNS 130908  
SWOD48  
SPC AC 130906  
 
DAY 4-8 CONVECTIVE OUTLOOK CORR 1  
NWS STORM PREDICTION CENTER NORMAN OK  
0406 AM CDT THU AUG 13 2026  
 
VALID 161200Z - 211200Z  
 
CORRECTED FOR TEXT  
   
..DISCUSSION
 
   
..D4/SUNDAY
 
 
STRONG TO POTENTIALLY SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP  
IN ASSOCIATION WITH A COLD FRONT THAT WILL MOVE ACROSS PARTS OF THE  
MIDWEST, OHIO VALLEY, AND NORTHERN MID-ATLANTIC ON SUNDAY.  
DEEP-LAYER SHEAR IS GENERALLY FORECAST TO REMAIN WEAK, BUT MODERATE  
UNIDIRECTIONAL WESTERLY FLOW (POTENTIALLY 30-40 KT IN THE 850-500 MB  
LAYER) WITHIN A FAVORABLY MOIST AND UNSTABLE ENVIRONMENT WILL  
SUPPORT POTENTIAL FOR MULTIPLE STORM CLUSTERS WITH WIND-DAMAGE  
POTENTIAL.  
 
UNCERTAINTY REMAINS REGARDING FRONTAL TIMING AND THE INFLUENCE (IF  
ANY) OF MCVS EMANATING FROM THE PLAINS AND MIDWEST. ALSO, GIVEN THE  
GENERALLY WEAK DEEP-LAYER SHEAR, THE MAGNITUDE OF THE SEVERE THREAT  
WILL BE STRONGLY INFLUENCED BY THE EXTENT OF PRE-CONVECTIVE HEATING  
AND STEEPENING OF LOW-LEVEL LAPSE RATES. CONFIDENCE IS TOO LOW TO  
ADD A 15% AREA AT THIS TIME, THOUGH SEVERE PROBABILITIES WILL LIKELY  
BE NEEDED LATER IN THE OUTLOOK CYCLE.  
   
..D5/MONDAY
 
 
THE FRONT WILL MOVE SOUTHEASTWARD ON MONDAY INTO PARTS OF THE  
MID-MS/LOWER OHIO VALLEYS AND MID-ATLANTIC/CAROLINAS. SCATTERED  
STORMS ARE AGAIN EXPECTED ALONG/AHEAD OF THE FRONT. SOME WEAKENING  
OF LOW/MIDLEVEL FLOW IS EXPECTED AND DEEP-LAYER SHEAR WILL REMAIN  
MODEST AT BEST, SO THE SEVERE THREAT MAY REMAIN RATHER ISOLATED.  
 
FARTHER WEST, INCREASING MOISTURE AND INSTABILITY WITHIN A MODEST  
WEST-NORTHWESTERLY FLOW REGIME COULD RESULT IN SOME SEVERE-STORM  
POTENTIAL FROM THE CENTRAL HIGH PLAINS INTO THE DAKOTAS.  
   
..D6/TUESDAY - D8/THURSDAY
 
 
PREDICTABILITY REGARDING THE UPPER-LEVEL PATTERN BEGINS TO WANE BY  
EARLY/MID NEXT WEEK. IN GENERAL, PERIODIC BOUTS OF SEVERE STORMS MAY  
CONTINUE ACROSS PARTS OF THE CENTRAL/NORTHERN PLAINS AND UPPER  
MIDWEST, ALONG THE PERIPHERY OF A PERSISTENT UPPER RIDGE. A  
LESS-ORGANIZED SEVERE THREAT MAY ALSO PERSIST NEAR THE REMNANT  
FRONTAL ZONE ACROSS PARTS OF THE SOUTHEAST/CAROLINAS.  
 
..DEAN.. 08/13/2026  
 
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