460  
ACUS02 KWNS 211721  
SWODY2  
SPC AC 211720  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1220 PM CDT MON APR 21 2025  
 
VALID 221200Z - 231200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE  
SOUTHERN HIGH PLAINS AND INTO PARTS OF SOUTHERN KANSAS...  
   
..SUMMARY  
 
ISOLATED TO SCATTERED SEVERE THUNDERSTORMS ARE POSSIBLE ON TUESDAY  
ACROSS PORTIONS OF THE SOUTHERN PLAINS.  
   
..SYNOPSIS  
 
A MOSTLY ZONAL PATTERN WILL BE IN PLACE ACROSS THE CONUS WITH  
MULTIPLE EMBEDDED WEAK SHORTWAVE TROUGHS ON TUESDAY. ONE SUCH TROUGH  
WHICH IS FORECAST TO MOVE ACROSS NEW MEXICO DURING THE AFTERNOON MAY  
RESULT IN SOME WEAK LEE TROUGHING AND SUPPORT THE POTENTIAL FOR  
ISOLATED TO SCATTERED SEVERE STORMS ALONG THE DRYLINE TUESDAY  
AFTERNOON.  
   
..SOUTHERN HIGH PLAINS  
 
LOW-LEVEL MOISTURE WILL ADVECT NORTHWARD ACROSS WEST TEXAS AHEAD OF  
A DRYLINE TUESDAY MORNING. STRONG SURFACE HEATING WILL LEAD TO  
MODERATE TO STRONG DESTABILIZATION ALONG AND AHEAD OF THE DRYLINE.  
FORECAST SOUNDINGS SHOW A WEAKLY CAPPED AIRMASS WHICH SHOULD BE  
SUFFICIENT FOR ISOLATED TO SCATTERED THUNDERSTORM DEVELOPMENT BY MID  
TO LATE AFTERNOON AS WEAK FORCING FROM THE MID-LEVEL TROUGH  
OVERSPREADS THE DRYLINE. 30 TO 35 KNOTS OF SHEAR SHOULD SUPPORT  
HIGH-BASED, SLOW-MOVING SUPERCELLS WITH A THREAT FOR LARGE HAIL AND  
SEVERE WIND GUSTS. AN ISOLATED TORNADO THREAT MAY ALSO EXIST WHERE  
BETTER LOW-LEVEL MOISTURE IS PRESENT, FARTHER SOUTH, AND WHERE  
INTERSECTING BOUNDARIES COULD ENHANCE LOW-LEVEL VORTICITY INGESTION.  
 
UPSCALE GROWTH MAY EVENTUALLY OCCUR WITH ONE OR MORE MCSS MOVING  
EAST INTO THE EVENING AND OVERNIGHT HOURS, SUPPORTED BY A MODESTLY  
ENHANCED LOW-LEVEL JET.  
   
..NORTHERN PANHANDLE INTO KANSAS  
 
A SURFACE FRONT IS FORECAST TO EXTEND ACROSS KANSAS AND INTO THE  
OK/NORTHERN TX PANHANDLE BY TUESDAY AFTERNOON. ONLY MODEST MOISTURE  
RECOVERY WILL OCCUR THIS FAR NORTH, BUT IT MAY BE SUFFICIENT FOR  
MODERATE INSTABILITY ALONG THE FRONT BY MID-AFTERNOON. 25 TO 30  
KNOTS OF SHEAR WILL SUPPORT SOME STORM ORGANIZATION. VERY STEEP  
LAPSE RATES AND A RELATIVELY DRY PROFILE WILL SUPPORT THE POTENTIAL  
FOR ISOLATED LARGE HAIL AND SEVERE WIND GUSTS.  
   
..IA/WI/IL  
 
A STALLED FRONTAL BOUNDARY WILL BE IN PLACE ACROSS THE MID-MO VALLEY  
INTO SOUTHERN WI ON TUESDAY. MODEST MOISTURE RETURN AND PERSISTENT  
ISENTROPIC ASCENT ALONG THIS BOUNDARY MAY BE SUFFICIENT FOR ISOLATED  
THUNDERSTORM DEVELOPMENT AMID WEAK DIURNAL DESTABILIZATION. LOW TO  
MIDLEVEL FLOW WILL REMAIN RATHER WEAK, BUT RAPIDLY INCREASE ABOVE  
700 MB, SUPPORTING EFFECTIVE SHEAR MAGNITUDES GREATER THAN 40 KT.  
COLD TEMPERATURES ALOFT (-17 C NEAR 500 MB) WILL SUPPORT MLCAPE TO  
AROUND 500 J/KG, AND ISOLATED CONVECTION COULD PRODUCE SPORADIC HAIL  
OR DAMAGING WIND GUSTS.  
   
..CAROLINAS  
 
A COLD FRONT ASSOCIATED WITH A SURFACE LOW OVER QUEBEC WILL MOVE  
SOUTHEAST ACROSS THE MID-ATLANTIC AND CAROLINAS DURING THE  
AFTERNOON/EVENING. STRONG HEATING OF A MODESTLY MOIST BOUNDARY LAYER  
AHEAD OF THE FRONT WILL SUPPORT A CORRIDOR OF MLCAPE UP TO 1000-1500  
J/KG. WEAK LOW-LEVEL SOUTHWESTERLY FLOW WILL INCREASE WITH HEIGHT,  
SUPPORT EFFECTIVE SHEAR MAGNITUDES UP TO 35 KT. THIS SHOULD BE  
SUFFICIENT FOR A FEW STRONGER/ORGANIZED CELLS. STEEP LOW-LEVEL LAPSE  
RATES AND SOMEWHAT ELONGATED HODOGRAPHS SUGGEST TRANSIENT SUPERCELLS  
CAPABLE OF STRONG GUSTS AND ISOLATED HAIL WILL BE POSSIBLE. IN  
ADDITION, ANY STORMS WHICH INTERACT WITH THE SEA BREEZE COULD HAVE  
LOCALLY ENHANCED UPDRAFTS AND A PERIODICALLY GREATER LARGE  
HAIL/DAMAGING WIND THREAT.  
 
..BENTLEY.. 04/21/2025  
 
 
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