699  
ACUS01 KWNS 191244  
SWODY1  
SPC AC 191242  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0742 AM CDT SAT APR 19 2025  
 
VALID 191300Z - 201200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
WEST-CENTRAL TEXAS...  
   
..SUMMARY  
 
SCATTERED SEVERE THUNDERSTORMS ARE LIKELY FROM PARTS OF TEXAS INTO  
SOUTHERN MISSOURI, MAINLY THIS AFTERNOON AND EVENING. LARGE TO VERY  
LARGE HAIL, DAMAGING WINDS, AND A FEW TORNADOES ALL APPEAR POSSIBLE.  
ISOLATED TO SCATTERED DAMAGING WINDS MAY ALSO OCCUR ACROSS PORTIONS  
OF THE OHIO VALLEY INTO THE NORTHEAST.  
   
..SOUTHERN PLAINS TO THE OZARKS  
 
MULTIPLE BANDS/CLUSTERS OF CONVECTION ARE ONGOING THIS MORNING FROM  
PARTS OF EASTERN OK NORTHEASTWARD TO THE OZARKS AND MID MS VALLEY.  
MUCH OF THIS ACTIVITY SHOULD REMAIN ELEVATED, WITH ISOLATED  
HAIL/WIND POTENTIAL IN THE SHORT TERM. IN THE WAKE OF THESE  
THUNDERSTORMS, AN UPPER TROUGH/LOW WILL EJECT FROM THE SOUTHWEST  
ACROSS THE SOUTHERN HIGH PLAINS THROUGH THE PERIOD. A FRONT SHOULD  
GENERALLY REMAIN STALLED ACROSS THE SOUTHERN PLAINS AND TOWARDS THE  
OZARKS TODAY, AS SURFACE CYCLOGENESIS OCCURS OVER FAR WEST TX. AS  
LARGE-SCALE ASCENT SPREADS EASTWARD OVER THE SOUTHERN HIGH PLAINS,  
ADDITIONAL ROBUST THUNDERSTORMS WILL LIKELY DEVELOP BY MID AFTERNOON  
ALONG/NEAR THE FRONT, AND A DRYLINE EXTENDING SOUTHWARD ACROSS WEST  
TX INTO NORTHERN MEXICO.  
 
DAYTIME HEATING OF A MOIST LOW-LEVEL AIRMASS, COMBINED WITH THE  
PRESENCE OF STEEP MID-LEVEL LAPSE RATES, ARE EXPECTED TO SUPPORT  
MODERATE INSTABILITY ACROSS THE WARM SECTOR, WITH PEAK MLCAPE VALUES  
POTENTIALLY REACHING UP TO 1500-2500 J/KG. STRONG DEEP-LAYER SHEAR  
AROUND 50-70 KT WILL SUPPORT INTENSE UPDRAFT ORGANIZATION WITH  
CONVECTION THAT DEVELOPS ALONG/NEAR THE FRONT AND DRYLINE THIS  
AFTERNOON. INITIAL SUPERCELLS WILL LIKELY POSE A THREAT FOR VERY  
LARGE HAIL AROUND 2-3 INCHES IN DIAMETER, ALONG WITH DAMAGING WINDS.  
BY EARLY EVENING, CONVECTIVE MODE SHOULD BECOME MESSIER AS A  
GRADUALLY STRENGTHENING LOW-LEVEL JET AND THE FRONT ENCOURAGE  
THUNDERSTORM INTERACTIONS/MERGERS. STILL, A CONTINUED LARGE HAIL AND  
DAMAGING WIND THREAT WILL LIKELY PERSIST FOR MUCH OF THE EVENING.  
STRENGTHENING LOW-LEVEL SHEAR IN TANDEM WITH THE INCREASING  
LOW-LEVEL JET SHOULD ALSO SUPPORT SOME THREAT FOR A FEW TORNADOES  
WITH ANY SUPERCELLS/CLUSTERS THAT CAN REMAIN SURFACE BASED THIS  
EVENING. GIVEN INCREASED CONFIDENCE IN MULTIPLE INTENSE SUPERCELLS  
DEVELOPING THIS AFTERNOON, AN ENHANCED RISK HAS BEEN INTRODUCED  
ACROSS PARTS OF WEST-CENTRAL TO WESTERN NORTH TX WITH THIS UPDATE.  
   
..MID MISSISSIPPI/OHIO VALLEYS TO THE NORTHEAST  
 
INSTABILITY IS EXPECTED TO REMAIN FAIRLY WEAK ALONG/AHEAD OF THE  
SURFACE FRONT EXTENDING FROM SOUTHERN MO ACROSS THE OH VALLEY AND  
INTO THE NORTHEAST. EVEN SO, STRONG WEST-SOUTHWESTERLY WINDS THROUGH  
LOW/MID-LEVELS MAY SUPPORT A THREAT FOR ISOLATED TO SCATTERED  
SEVERE/DAMAGING WINDS AS THE BOUNDARY LAYER GRADUALLY DESTABILIZES  
THROUGH THE DAY. MULTIPLE ONGOING CLUSTERS OF ELEVATED CONVECTION  
FROM THE OZARKS TO THE MID MS AND LOWER OH VALLEYS MAY BECOME  
SURFACE BASED OVER THE NEXT SEVERAL HOURS WITH FILTERED DAYTIME  
HEATING. HAVE THEREFORE EXPANDED THE SLIGHT RISK FOR DAMAGING WINDS  
NORTHEASTWARD ACROSS THESE AREAS IN A NARROW ZONE ALONG/NEAR THE  
FRONT.  
 
A RATHER STRONG MID-LEVEL JET WILL OVERSPREAD THE NORTHERN  
MID-ATLANTIC INTO THE NORTHEAST TODAY, AS AN UPPER TROUGH DEVELOPS  
EASTWARD OVER THE GREAT LAKES AND EASTERN CANADA. ALTHOUGH LOW-LEVEL  
MOISTURE IS FORECAST TO REMAIN LIMITED, COLD TEMPERATURES ALOFT  
SHOULD AID IN MODEST DESTABILIZATION BY EARLY AFTERNOON IN A NARROW  
CORRIDOR ALONG/AHEAD OF THE EASTWARD-MOVING COLD FRONT. DEEP-LAYER  
SHEAR WILL BE STRONG ENOUGH TO CONDITIONALLY SUPPORT SUPERCELLS,  
ALTHOUGH THERE SHOULD BE A TENDENCY FOR CONVECTION THAT DEVELOPS  
ALONG THE FRONT TO BECOME MORE LINEAR WITH TIME. BASED ON RECENT  
GUIDANCE TRENDS, HAVE EXPANDED THE MARGINAL RISK FOR HAIL/DAMAGING  
WIND POTENTIAL EASTWARD ACROSS THESE AREAS. GREATER SEVERE WIND  
PROBABILITIES MAY BE NEEDED IF CONFIDENCE INCREASES IN A ORGANIZED  
CLUSTER DEVELOPING.  
 
..GLEASON/BROYLES.. 04/19/2025  
 
 
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