558  
ACUS01 KWNS 211617  
SWODY1  
SPC AC 211615  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1115 AM CDT THU MAY 21 2026  
 
VALID 211630Z - 221200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND  
EVENING OVER PARTS OF EASTERN COLORADO....  
   
..SUMMARY  
 
THUNDERSTORMS CAPABLE OF PRODUCING LARGE HAIL AND ISOLATED SEVERE  
GUSTS SHOULD OCCUR ACROSS PARTS OF THE CENTRAL/SOUTHERN HIGH PLAINS  
THIS AFTERNOON AND EVENING. A TORNADO OR TWO MAY ALSO OCCUR.  
   
..HIGH PLAINS  
 
WATER VAPOR IMAGERY SHOWS AN UPPER TROUGH MOVING ACROSS WESTERN  
WY/CO. THIS FEATURE WILL SPREAD WEAK/BROAD LARGE SCALE FORCING FOR  
ASCENT ACROSS MUCH OF THE HIGH PLAINS FROM SD TO NM THIS AFTERNOON.  
AT THE SURFACE, SOUTHERLY LOW LEVEL WINDS HAVE RESULTED IN AN AXIS  
OF 40S/50S DEWPOINTS ALONG THIS CORRIDOR. LOW CLOUDS ARE SLOWLY  
ERODING, WHICH SHOULD RESULT IN MODERATE CAPE VALUES AND AID IN THE  
DEVELOPMENT OF WIDELY SCATTERED AFTERNOON THUNDERSTORMS.  
 
ISOLATED STORMS WILL LIKELY FORM FIRST OVER PARTS OF EASTERN NM.  
THIS ACTIVITY WILL BUILD SLOWLY EASTWARD TOWARD WEST TX WITH A RISK  
OF LARGE HAIL.  
 
BY MID/LATE AFTERNOON, STORMS WILL LIKELY DEVELOP OFF THE RATON AND  
PALMER RIDGES, SPREADING EASTWARD TOWARD WESTERN KS THIS EVENING.  
SHEAR PROFILES IN THIS AREA WILL BE STRONGER THAN FARTHER SOUTH,  
SUPPORTING LONGER-LIVED STORMS CAPABLE OF LARGE HAIL, DAMAGING  
WINDS, AND PERHAPS A TORNADO OR TWO.  
 
AN ISOLATED CELL OR TWO MAY ALSO PRODUCE OCCASIONAL SEVERE HAIL OVER  
PARTS OF EASTERN WY AND INTO THE BLACK HILLS REGION LATER THIS  
AFTERNOON.  
   
..CAROLINAS/VA  
 
CLEAR SKIES ARE LEADING TO STRONG HEATING OVER PARTS OF SOUTHERN VA  
INTO PART OF NC/SC. SCATTERED AFTERNOON THUNDERSTORMS ARE EXPECTED  
TO FORM IN THIS ZONE, WITH STEEP LOW-LEVEL LAPSE RATES AND  
SUFFICIENT CAPE SUPPORTING A RISK OF GUSTY/DAMAGING WINDS IN THE  
STRONGEST CELLS.  
 
..HART/LYONS.. 05/21/2026  
 
 
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