092  
ACUS01 KWNS 261647  
SWODY1  
SPC AC 261645  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1145 AM CDT MON MAY 26 2025  
 
VALID 261630Z - 271200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS TEXAS  
EDWARDS PLATEAU/SOUTH-CENTRAL TEXAS...  
   
..SUMMARY  
 
SEVERE THUNDERSTORMS ARE EXPECTED FROM PARTS OF THE SOUTHERN PLAINS  
EASTWARD INTO THE LOWER MISSISSIPPI VALLEY. VERY LARGE HAIL IS  
POSSIBLE IN PARTS OF WEST-CENTRAL/SOUTH-CENTRAL TEXAS INCLUDING THE  
EDWARDS PLATEAU/HILL COUNTRY, WITH SEVERE/DAMAGING WINDS BECOMING A  
GREATER CONCERN THIS AFTERNOON/EVENING.  
   
..TEXAS EDWARDS PLATEAU/HILL COUNTRY AND SOUTH-CENTRAL TEXAS  
 
POST-MCS OUTFLOW CONTINUES TO SETTLE SOUTHWARD ACROSS  
SOUTH-CENTRAL/SOUTHEAST TEXAS AT MIDDAY. STRONG DAYTIME HEATING IS  
ANTICIPATED ACROSS WEST-CENTRAL TEXAS INCLUDING THE EDWARDS PLATEAU  
VICINITY AS A WEAK UPPER TROUGH MOVES SLOWLY EASTWARD ACROSS THE  
SOUTHERN/CENTRAL PLAINS THROUGH THIS EVENING. THE FRONT AND STALLING  
COMPOSITE OUTFLOW BOUNDARY WILL INFLUENCE ANTICIPATED DEEP  
CONVECTIVE DEVELOPMENT LATER TODAY. STRONG TO LOCALLY EXTREME  
INSTABILITY WILL LIKELY DEVELOP BY PEAK AFTERNOON HEATING, WITH  
STEEP MID-LEVEL LAPSE RATES CONTRIBUTING TO THIS AMPLE BUOYANCY.  
 
CURRENT EXPECTATIONS ARE FOR MULTIPLE THUNDERSTORMS TO INITIATE  
LATER THIS AFTERNOON ALONG/NEAR THE BOUNDARIES ACROSS THE CONCHO  
VALLEY/EASTERN PERMIAN BASIN AND EDWARDS PLATEAU AND QUICKLY BECOME  
SEVERE. ALTHOUGH LOW-LEVEL WINDS ARE FORECAST TO REMAIN MODEST,  
MID/UPPER-LEVEL WEST-SOUTHWESTERLY FLOW GRADUALLY STRENGTHENING WITH  
HEIGHT SHOULD SUPPORT AROUND 40-50 KT OF EFFECTIVE BULK SHEAR. THIS  
WILL EASILY FOSTER INTENSE SUPERCELLS WITH THE INITIAL DEVELOPMENT  
THIS AFTERNOON, AND LARGE TO VERY LARGE HAIL (SOME 2+ INCHES IN  
DIAMETER) APPEARS LIKELY. SOME TORNADO POTENTIAL WILL EXIST AS WELL.  
WITH TIME, CLUSTERING/UPSCALE GROWTH IS ANTICIPATED AS THUNDERSTORMS  
SPREAD EAST-SOUTHEASTWARD TOWARD THE HILL COUNTRY AND I-35 CORRIDOR  
WITH AN INCREASING SEVERE WIND POTENTIAL INTO THIS EVENING.  
   
..LOWER MISSISSIPPI VALLEY/SOUTHEAST  
 
A WELL-ORGANIZED CONVECTIVE LINE EXTENDS LATE THIS MORNING ACROSS  
THE ARKLAMISS INTO SOUTHWEST LOUISIANA, WHICH THE MOST  
ORGANIZED/STRONGEST PORTION OF THE LINE COINCIDENT WITH AREAS  
ALONG/NORTH OF A MODIFYING RESIDUAL BOUNDARY AS A BYPRODUCT OF  
YESTERDAY'S CONVECTION. DAMAGING WIND POTENTIAL MAY MODESTLY  
INCREASE AS THE BOUNDARY LAYER DIURNALLY WARMS. FOR ADDITIONAL  
DETAILS, SEE MESOSCALE DISCUSSION 988.  
 
SOME GUIDANCE, PARTICULARLY MULTIPLE RECENT NAM RUNS (BUT EVEN RAP  
TO SOME EXTENT), IS INSISTENT THAT THE MCV NEAR THE ARKLATEX WILL  
MAINTAIN ITS INTEGRITY THROUGH THE DAY INTO TONIGHT, WITH A RELATED  
EAST-NORTHEASTWARD TRANSITION OVER THE ARKLAMISS TOWARD THE  
TENNESSEE VALLEY IN VICINITY OF THE OLD SYNOPTIC FRONT. MCS ASIDE,  
AN MCV-RELATED ENHANCED LOW/MID-LEVEL FLOW FIELD COULD INFLUENCE  
SOME SUPERCELL/TORNADO POTENTIAL LATER TODAY ACROSS MISSISSIPPI INTO  
ALABAMA, ALTHOUGH PRIOR-DAY OUTFLOW/CONVECTIVE OVERTURNING AND  
EXISTING CONVECTION ARE MAJOR POINTS OF UNCERTAINTY FOR SUCH  
POTENTIAL.  
   
..SOUTHERN/CENTRAL HIGH PLAINS  
 
A MODEST LOW-LEVEL UPSLOPE FLOW REGIME WILL PERSIST TODAY ACROSS  
PARTS OF THE SOUTHERN/CENTRAL HIGH PLAINS TO THE NORTH OF A SURFACE  
FRONT. WHILE INSTABILITY SHOULD REMAIN LIMITED, ISOLATED TO WIDELY  
SCATTERED CONVECTION SHOULD INITIALLY DEVELOP OVER THE HIGHER  
TERRAIN, BEFORE SUBSEQUENTLY SPREADING EASTWARD ACROSS THE ADJACENT  
HIGH PLAINS THROUGH THE AFTERNOON/EVENING. OCCASIONAL LARGE HAIL AND  
WINDS MAY OCCUR WITH THIS ACTIVITY, WITH SOME GUIDANCE SUGGESTING A  
SMALL CLUSTER MAY EVENTUALLY DEVELOP THIS EVENING ACROSS EASTERN NEW  
MEXICO INTO NORTHWEST TEXAS. THIS SCENARIO WILL BE REEVALUATED INTO  
MID-AFTERNOON FOR ANY POTENTIAL SLIGHT RISK UPGRADE.  
 
..GUYER/LYONS.. 05/26/2025  
 
 
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