267  
ACUS03 KWNS 210724  
SWODY3  
SPC AC 210723  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0223 AM CDT SUN JUN 21 2026  
 
VALID 231200Z - 241200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF  
THE CENTRAL HIGH PLAINS...  
   
..SUMMARY
 
 
SCATTERED SEVERE STORMS ARE EXPECTED ACROSS THE CENTRAL HIGH PLAINS  
ON TUESDAY WITH ISOLATED SEVERE STORMS POSSIBLE INTO THE UPPER  
MIDWEST. LARGE HAIL AND DAMAGING WIND GUSTS WILL BE THE PRIMARY  
THREATS.  
   
..SYNOPSIS
 
 
A LOW-AMPLITUDE RIDGE ACROSS THE WESTERN CONUS WILL BUILD SLOWLY  
NORTHWARD AS A TROUGH MOVES SOUTH FROM ALBERTA INTO THE NORTHERN  
PLAINS. AS THIS PATTERN CONTINUES TO EVOLVE, MID-LEVEL FLOW WILL  
STRENGTHEN ACROSS THE ROCKIES AND INTO THE PLAINS. THIS WILL RESULT  
IN STRENGTHENING LEE CYCLOGENESIS ACROSS THE SOUTHERN HIGH PLAINS.  
FARTHER EAST, A COLD FRONT WILL MOVE OFF OF THE EAST COAST DURING  
THE DAY TUESDAY.  
   
..CENTRAL HIGH PLAINS INTO THE CENTRAL PLAINS
 
 
STRENGTHENING UPSLOPE FLOW TO THE NORTH OF THE DEVELOPING LEE  
CYCLONE SHOULD RESULT IN STORM DEVELOPMENT BY MID-AFTERNOON ACROSS  
EASTERN COLORADO ON TUESDAY. AS MID-LEVEL FLOW STRENGTHENS TO NEAR  
50 KNOTS, THIS STRONG SHEAR COMBINED WITH MODERATE TO STRONG  
INSTABILITY WILL SUPPORT SUPERCELLS CAPABLE OF LARGE TO VERY LARGE  
HAIL AND SOME SEVERE WINDS. EXPECT THESE SUPERCELLS TO EVENTUALLY  
CONGEAL INTO ONE OR MORE CLUSTERS AS THEY MOVE EAST DURING THE  
EVENING, WITH AN INCREASING SEVERE WIND THREAT.  
   
..UPPER MIDWEST
 
 
A WEAK SURFACE LOW ASSOCIATED WITH THE MID-LEVEL TROUGH MOVING SOUTH  
OUT OF CANADA WILL SETTLE INTO THE UPPER MIDWEST ON TUESDAY. A COLD  
FRONT WILL EXTEND SOUTHWESTWARD FROM THIS FEATURE WITH DEWPOINTS  
INTO THE LOW 60S AHEAD OF IT. THIS SHOULD PRODUCE SUFFICIENT  
INSTABILITY FOR SCATTERED STORM DEVELOPMENT. SOME DAMAGING WIND  
GUSTS MAY BE POSSIBLE WITH THE STRONGEST STORMS.  
   
..SOUTHEAST
 
 
A COLD FRONT WILL MOVE OFF THE EAST COAST DURING THE DAY ON TUESDAY.  
MOST GUIDANCE SHOWS THE FRONT OFFSHORE BEFORE SUFFICIENT INSTABILITY  
DEVELOPS FOR A SEVERE STORM THREAT ALONG THE GEORGIA, SOUTH  
CAROLINA, AND NORTH CAROLINA COASTS. THEREFORE, HAVE NOT ADDED  
PROBABILITIES AT THIS TIME. HOWEVER, IF THE COLD FRONT SLOWS OR IF  
GREATER INSTABILITY DEVELOPS THAN CURRENTLY FORECAST, A MARGINAL  
RISK MAY BE NEEDED IN LATER OUTLOOKS.  
 
..BENTLEY.. 06/21/2026  
 

 
 
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