170  
ACUS02 KWNS 221721  
SWODY2  
SPC AC 221719  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1219 PM CDT TUE SEP 22 2026  
 
VALID 231200Z - 241200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
EASTERN TN AND VICINITY...  
   
..SUMMARY  
 
STRONG TO LOCALLY SEVERE STORMS ARE POSSIBLE ACROSS PARTS OF EASTERN  
TENNESSEE AND VICINITY ON WEDNESDAY.  
   
..EASTERN TN AND VICINITY  
 
A MID/UPPER-LEVEL TROUGH WILL REMAIN IN PLACE OVER MOST OF THE EAST  
ON WEDNESDAY. A REINFORCING SHORTWAVE TROUGH AND ATTENDANT JET  
MAXIMUM ARE FORECAST TO MOVE FROM THE LOWER OHIO VALLEY TOWARD THE  
SOUTHERN APPALACHIANS THROUGH THE DAY. A NARROW ZONE OF MODERATE  
DESTABILIZATION IS EXPECTED TO DEVELOP DURING THE AFTERNOON FROM  
NORTHEAST AL INTO EASTERN TN AND SOUTHEAST KY, IN THE VICINITY OF AN  
INVERTED SURFACE TROUGH. THE APPROACHING SHORTWAVE TROUGH AND  
TERRAIN-RELATED CIRCULATIONS WILL RESULT IN THUNDERSTORM DEVELOPMENT  
DURING THE AFTERNOON.  
 
THE GREATEST STORM COVERAGE IS CURRENTLY EXPECTED IN THE VICINITY OF  
EASTERN TN, WHERE EFFECTIVE SHEAR WILL GENERALLY BE IN THE 25-30 KT  
RANGE, WITH MODESTLY ELONGATED MID/UPPER-LEVEL HODOGRAPHS. THE  
ENVIRONMENT WILL SUPPORT AT LEAST BRIEF STORM ORGANIZATION, WITH  
LOCALIZED HAIL AND STRONG/DAMAGING GUSTS POSSIBLE. A  
LEVEL-1/MARGINAL RISK HAS BEEN ADDED WHERE RELATIVE CONFIDENCE IS  
HIGHEST IN STRONG DIURNAL STORM DEVELOPMENT. DEEP-LAYER SHEAR WILL  
BE SOMEWHAT STRONGER INTO CENTRAL AL/WEST-CENTRAL GA, THOUGH  
SUBSTANTIAL MIDLEVEL DRYNESS AND WARMER TEMPERATURES ALOFT MAY TEND  
TO LIMIT STORM COVERAGE WITH SOUTHWARD EXTENT.  
   
..NORTHERN HIGH PLAINS  
 
A MID/UPPER-LEVEL SHORTWAVE TROUGH WILL MOVE ACROSS THE DAKOTAS ON  
WEDNESDAY. THE RELATIVELY EARLY TIMING OF THIS SYSTEM WILL NOT BE  
IDEAL FOR SURFACE-BASED DEVELOPMENT LATER IN THIS AFTERNOON ACROSS  
THE NORTHERN HIGH PLAINS, WHERE SOME DIURNAL DESTABILIZATION IS  
EXPECTED. ISOLATED STRONG STORM DEVELOPMENT CANNOT BE RULED OUT IN  
THIS AREA, WHILE GENERALLY WEAK ELEVATED CONVECTION IS EXPECTED  
FARTHER EAST ACROSS THE EASTERN DAKOTAS INTO MN.  
   
..SOUTHERN HIGH PLAINS  
 
RELATIVELY WIDESPREAD CONVECTION IS EXPECTED FROM EASTERN NM INTO  
THE OK/TX PANHANDLES, IN ASSOCIATION WITH A MID/UPPER-LEVEL TROUGH  
MOVING NORTHWARD OUT OF MEXICO. GENERALLY WEAK LAPSE RATES AND  
BUOYANCY ARE EXPECTED TO LIMIT SEVERE POTENTIAL, THOUGH A STRONG  
STORM OR TWO CANNOT BE RULED OUT, GIVEN THE PRESENCE OF VEERING WIND  
PROFILES AND 25-35 KT OF EFFECTIVE SHEAR.  
 
..DEAN.. 09/22/2026  
 
 
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