812  
ACUS01 KWNS 191954  
SWODY1  
SPC AC 191953  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0253 PM CDT TUE MAY 19 2026  
 
VALID 192000Z - 201200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE LOWER  
OHIO VALLEY INTO THE LOWER GREAT LAKES...AND PARTS OF CENTRAL/SOUTH  
TEXAS...  
   
..SUMMARY  
 
SCATTERED SEVERE THUNDERSTORMS WILL BE POSSIBLE TODAY FROM THE  
SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY/MID-SOUTH, OHIO  
VALLEY, AND LOWER GREAT LAKES. DAMAGING WINDS AND HAIL WILL BE THE  
PRIMARY THREATS. A GREATER THREAT FOR LARGE TO VERY LARGE HAIL  
SHOULD EXIST ACROSS PARTS OF WEST-CENTRAL TEXAS.  
   
..20Z UPDATE  
 
THE PRIMARY CHANGE TO THE FORECAST WAS TO INCREASE WIND  
PROBABILITIES IN PARTS OF SOUTH TEXAS. CONVECTION WITHIN THE ROLLING  
PLAINS SHOULD CONTINUE TO DEVELOP THIS AFTERNOON ALONG A SLOWLY  
MOVING COLD FRONT. GIVEN THE MOISTURE SURGE AHEAD OF THIS ACTIVITY,  
IT SEEMS PLAUSIBLE THAT COLD POOL DEVELOPMENT WILL BE ROBUST ENOUGH  
TO SUPPORT CONTINUED DEVELOPMENT SOUTHWARD INTO THE OVERNIGHT.  
RECENT HRRR GUIDANCE AND THE ECMWF SUPPORT THIS POSSIBILITY.  
ELSEWHERE, ONLY MINOR CHANGES WHERE MADE BASED ON CURRENT  
OBSERVATIONS.  
 
..WENDT.. 05/19/2026  
   
PREV DISCUSSION  
/ISSUED 1119 AM CDT TUE MAY 19 2026/  
   
..OH VALLEY AND LOWER GREAT LAKES  
 
DEEP SOUTHWESTERLY FLOW IS PRESENT TODAY FROM SOUTHERN IL INTO MUCH  
OF THE OH VALLEY AND NY. VISIBLE SATELLITE IMAGERY SHOWS MOSTLY  
CLEAR SKIES IN THE REGION, ALLOWING STRONG DESTABILIZATION AND  
STEEPENING LOW-LEVEL LAPSE RATES. THE RESULT WILL BE A RATHER LARGE  
ZONE OF FAVORABLE ENVIRONMENT FOR STRONG/DAMAGING WIND GUSTS THIS  
AFTERNOON WITH ANY ORGANIZED CONVECTION. GIVEN THE CONTINUED TREND  
IN MORNING MODEL GUIDANCE OF SCATTERED CLUSTERS OF STORMS IN THIS  
CORRIDOR, THE SLGT RISK AREA HAS BEEN MAINTAINED.  
   
..SOUTH-CENTRAL TX  
 
A WARM/MOIST AND UNSTABLE AIR MASS WILL DEVELOP THIS AFTERNOON  
ACROSS PARTS OF WEST-CENTRAL TX. SCATTERED THUNDERSTORM DEVELOPMENT  
IS EXPECTED ALONG A COLD FRONT SAGGING INTO THE REGION. WITH WEAK  
SUPERCELLS STRUCTURES POSSIBLE. THESE STORMS WILL TRACK  
SOUTHEASTWARD THROUGH THE LATE AFTERNOON/EVENING WITH A LARGE HAIL  
THREAT. EVENTUAL UPSCALE GROWTH INTO BOWING STRUCTURES MAY EXTEND  
THE SEVERE RISK OVERNIGHT INTO SOUTH-CENTRAL TX.  
   
..EAST TX/LA/AR  
 
WIDESPREAD OVERNIGHT CONVECTION CONTINUES TO BUILD SOUTHEASTWARD  
ACROSS SOUTHEAST OK AND WESTERN AR. THIS ACTIVITY WILL PERSIST MUCH  
OF THE DAY AND SPREAD ACROSS MUCH OF AR/EAST TX/NORTHERN LA, IN A  
REGION OF RELATIVELY WEAK VERTICAL SHEAR AND POOR LAPSE RATES.  
STORMS MAY OCCASIONALLY POSE A RISK OF GUSTY/DAMAGING WINDS, BUT THE  
OVERALL THREAT APPEARS MARGINAL.  
 
 
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