071  
ACUS01 KWNS 211231  
SWODY1  
SPC AC 211230  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0730 AM CDT SAT MAR 21 2026  
 
VALID 211300Z - 221200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE SOUTHERN APPALACHIANS/SOUTHEAST...  
   
..SUMMARY
 
 
ISOLATED STRONG TO SEVERE THUNDERSTORMS MAY PRODUCE MARGINALLY  
SEVERE HAIL AND DAMAGING WINDS THIS AFTERNOON AND EVENING ACROSS  
PARTS OF THE SOUTHERN APPALACHIANS/SOUTHEAST.  
   
..SOUTHERN APPALACHIANS/SOUTHEAST
 
 
WITH UPPER RIDGING PERSISTING OVER THE SOUTHWEST AND NORTHERN MEXICO  
TODAY, A SUBTLE MID-LEVEL SHORTWAVE TROUGH WILL MOVE SOUTHEASTWARD  
FROM THE MID MS VALLEY/MID-SOUTH THIS MORNING TOWARDS THE SOUTHERN  
APPALACHIANS VICINITY BY THIS EVENING. AT THE SURFACE, A WEAK FRONT  
DRAPED GENERALLY EAST-WEST ACROSS THE OH VALLEY SHOULD LIFT  
NORTHWARD AS A WARM FRONT THROUGH THE AFTERNOON, WITH MODEST  
LOW-LEVEL MOISTURE ADVANCING NORTHWARD ACROSS PARTS OF THE LOWER MS  
VALLEY, TN VALLEY, AND SOUTHEAST.  
 
LARGE-SCALE ASCENT ASSOCIATED WITH THE SHORTWAVE TROUGH SHOULD  
REMAIN RATHER WEAK, BUT DAYTIME HEATING AND OROGRAPHIC CIRCULATIONS  
OVER THE SOUTHERN APPALACHIANS MAY AID ISOLATED THUNDERSTORM  
DEVELOPMENT BY MID TO LATE AFTERNOON (AROUND 20-22Z). MOST GUIDANCE,  
WITH THE EXCEPTION OF THE NAM, SUGGESTS THAT BOUNDARY-LAYER MOISTURE  
WILL REMAIN QUITE LIMITED THIS AFTERNOON, WITH SURFACE DEWPOINTS  
GENERALLY IN THE 40S TO LOW 50S. EVEN SO, WEAK INSTABILITY/STEEPENED  
LOW-LEVEL LAPSE RATES MAY SUPPORT OCCASIONAL STRONG TO DAMAGING  
DOWNDRAFT WINDS WITH ANY THUNDERSTORMS THAT CAN DEVELOP FROM EASTERN  
TN INTO PARTS OF THE CAROLINAS. AROUND 25-30 KT OF EFFECTIVE BULK  
SHEAR MAY ALSO AID MODEST UPDRAFT ORGANIZATION AND MARGINALLY SEVERE  
HAIL WITH THE STRONGEST CORES. THE ISOLATED SEVERE THREAT SHOULD  
WANE THROUGH THE EVENING WITH THE LOSS OF DAYTIME HEATING.  
 
..GLEASON/KERR.. 03/21/2026  
 

 
 
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