121  
ACUS01 KWNS 211938  
SWODY1  
SPC AC 211937  
 
DAY 1 CONVECTIVE OUTLOOK CORR 1  
NWS STORM PREDICTION CENTER NORMAN OK  
0237 PM CDT SAT MAR 21 2026  
 
VALID 212000Z - 221200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE  
SOUTHERN APPALACHIANS TO THE CAROLINAS...  
 
CORRECTED FOR GEOGRAPHIC AREA HEADLINE  
   
..SUMMARY
 
 
ISOLATED STRONG TO SEVERE THUNDERSTORMS MAY PRODUCE MARGINALLY  
SEVERE HAIL AND DAMAGING WINDS THIS AFTERNOON AND EVENING FROM THE  
SOUTHERN APPALACHIANS INTO THE CAROLINAS.  
   
..20Z UPDATE
 
 
THE PREVIOUS FORECAST (SEE BELOW), REMAINS ON TRACK. PLEASE SEE  
MESOSCALE DISCUSSION 283 FOR SHORT-TERM INFORMATION ON THE SEVERE  
THREAT ACROSS PORTIONS OF THE SOUTHERN APPALACHIANS.  
 
..SQUITIERI.. 03/21/2026  
   
PREV DISCUSSION
 
/ISSUED 1129 AM CDT SAT MAR 21 2026/  
   
..SOUTHERN APPALACHIANS INTO THE CAROLINAS
 
 
RECENT SATELLITE IMAGERY SHOWS A SOMEWHAT SUBTLE AND BROAD SHORTWAVE  
TROUGH PROGRESSING SOUTHEASTWARD THROUGH THE MS VALLEY, ALONG THE  
FAR NORTHEAST PERIPHERY OF THE UPPER RIDGING COVERING MUCH OF THE  
SOUTHWEST AND SOUTHERN PLAINS. LIMITED LOW-LEVEL MOISTURE PRECEDES  
THIS WAVE, WITH RECENT SURFACE ANALYSIS SAMPLING DEWPOINTS RANGING  
FROM THE UPPER 50S ACROSS MUCH OF AL TO THE MID 40S ACROSS MUCH OF  
THE CAROLINAS. MODEST LOW-LEVEL MOISTURE ADVECTION IS ANTICIPATED  
TODAY AHEAD OF THIS WAVE. HOWEVER, THIS ADVECTION WILL BE COUNTERED  
BY DIURNAL MIXING, AND THE GENERAL EXPECTATION IS FOR DEWPOINTS TO  
BE IN THE UPPER 40S/LOW 50S FROM EASTERN TN INTO THE CAROLINAS AS  
THE WAVE MOVES IN THE AREA THIS AFTERNOON. EVEN WITH THIS LIMITED  
LOW-LEVEL MOISTURE, COOL MID-LEVEL TEMPERATURES AND ASSOCIATED STEEP  
MID-LEVEL LAPSE RATES WILL SUPPORT WEAK BUOYANCY AND THE POTENTIAL  
FOR ISOLATED TO WIDELY SCATTERED THUNDERSTORMS THIS AFTERNOON AND  
EARLY EVENING.  
 
LARGE-SCALE ASCENT WILL BE MODEST, SUPPORTING AN INITIALLY MORE  
CELLULAR, LOOSELY ORGANIZED STORM MODE. THIS REGION WILL BE ON THE  
SOUTHERN PERIPHERY OF THE STRONGER MID-LEVEL FLOW, LIKELY RESULTING  
IN SUFFICIENT SHEAR FOR ORGANIZATION WITHIN ANY DEEPER, MORE  
PERSISTENT UPDRAFTS. AS SUCH, UPDRAFTS ARE EXPECTED TO GRADUALLY  
INTENSIFY AS THEY MOVE INTO THE WESTERN AND CENTRAL CAROLINAS.  
MARGINALLY SEVERE HAIL IS POSSIBLE WITH THE STRONGEST CORES. A TREND  
TOWARDS A MORE LINEAR/LINE SEGMENT MODE IS EXPECTED WITH TIME, AND  
PERSISTENT STEEP LOW-LEVEL LAPSE RATES MAY SUPPORT OCCASIONAL STRONG  
TO DAMAGING DOWNDRAFT WINDS AS WELL. THE ONSET OF NOCTURNAL  
BOUNDARY-LAYER STABILIZATION SHOULD RESULT IN A DECREASING SEVERE  
THREAT AS THE STORMS MOVE INTO THE COASTAL CAROLINAS.  
 

 
 
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