643  
ACUS01 KWNS 271957  
SWODY1  
SPC AC 271955  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0255 PM CDT TUE MAY 27 2025  
 
VALID 272000Z - 281200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF  
SOUTHWESTERN INTO DEEP SOUTH TEXAS...AND PARTS OF THE GULF COAST  
STATES...  
   
..SUMMARY  
 
SCATTERED STRONG TO SEVERE THUNDERSTORMS REMAIN POSSIBLE ACROSS  
PARTS OF THE SOUTHERN PLAINS TO THE SOUTHEAST. LARGE TO VERY LARGE  
HAIL AND SEVERE WINDS SHOULD BE THE MAIN THREATS ACROSS WESTERN AND  
SOUTHERN PORTIONS OF TEXAS, WITH DAMAGING WINDS THE PRIMARY CONCERN  
ACROSS THE SOUTHEAST.  
   
..20Z UPDATE  
 
THE PREVIOUS FORECAST REMAINS ON TRACK. CONSIDERATION WAS GIVEN TO  
TRIM THE SLIGHT RISK ACROSS PORTIONS OF EASTERN LA INTO SOUTHERN MS  
WITH THE PASSAGE OF AN EARLIER QLCS. HOWEVER, SURFACE OBSERVATIONS  
SHOW TEMPERATURES REACHING 90 F IN SPOTS, INDICATING ROBUST ENOUGH  
MODIFICATION OF THE BOUNDARY LAYER TO SUPPORT SOME ORGANIZED SEVERE  
POTENTIAL WITH AN EXPECTED SECOND ROUND OF STORMS THIS EVENING.  
SEVERE WIND AND HAIL IS STILL EXPECTED TO ACCOMPANY THE STRONGER  
STORMS THAT FORM TO THE LEE OF THE CENTRAL/SOUTHERN ROCKIES, WITH  
POTENTIALLY 2+ INCH HAIL POSSIBLE WITH STORMS CLOSER TO THE RIO  
GRANDE.  
 
..SQUITIERI.. 05/27/2025  
   
PREV DISCUSSION  
/ISSUED 1139 AM CDT TUE MAY 27 2025/  
   
..SOUTHEAST STATES  
 
A MODESTLY ORGANIZED QUASI-LINEAR CLUSTER PERSISTS AT MIDDAY ACROSS  
EAST-CENTRAL/SOUTHWEST ALABAMA, WITH A TRAILING MCV NEAR THE  
MISSISSIPPI AND ALABAMA BORDER. THESE STORMS WILL CONTINUE GENERALLY  
EASTWARD AND POTENTIALLY INTENSIFY ALONG THE COMPOSITE OUTFLOW  
THROUGH THE AFTERNOON INTO AREAS ALONG/SOUTH OF A FRONT ACROSS  
GEORGIA, WITH AT LEAST ISOLATED DAMAGING WIND POTENTIAL. WHILE NOT  
CERTAIN, SOME SHORT-TERM GUIDANCE SUGGESTS THAT A DEGREE OF AIR MASS  
RECOVERY AND ABATEMENT OF OUTFLOW COULD ALLOW FOR STRONG/LOCALIZED  
SEVERE STORM REDEVELOPMENT NEAR THE SYNOPTIC FRONT LATER TODAY  
FARTHER WEST ACROSS SOUTHERN MISSISSIPPI AND POSSIBLY NEARBY  
LOUISIANA.  
   
..SOUTHERN PLAINS INCLUDING WEST/SOUTH TEXAS  
 
IN THE WAKE OF LAST NIGHT'S EXTENSIVE STORMS AND PROMINENT OUTFLOW  
NOW OVER THE WESTERN GULF, SUBSTANTIAL CONVECTIVE DEVELOPMENT SHOULD  
FOCUS LATER TODAY OVER PORTIONS OF WEST/SOUTH TEXAS, AS A WEAK  
MID-LEVEL SHORTWAVE TROUGH MOVES FROM NORTHWEST/NORTH-CENTRAL MEXICO  
INTO THE SOUTHWEST AND SOUTHERN HIGH PLAINS. WEAK LOW-LEVEL UPSLOPE  
FLOW AGAINST THE HIGHER TERRAIN IN WEST TEXAS AND NORTHERN MEXICO  
MAY ALSO AID THUNDERSTORM DEVELOPMENT. MOST GUIDANCE SUGGESTS THAT  
MODERATE TO LOCALLY STRONG INSTABILITY WILL EXIST BY PEAK AFTERNOON  
HEATING, WITH STEEP MID-LEVEL LAPSE RATES ONCE AGAIN OVERSPREADING  
THE WARM SECTOR FROM HIGHER TERRAIN TO THE SOUTH/WEST.  
 
MID-LEVEL WESTERLY FLOW IS EXPECTED TO REMAIN FAIRLY MODEST, BUT  
VEERING AND GRADUAL STRENGTHENING WITH HEIGHT THROUGH MID/UPPER  
LEVELS SHOULD SUPPORT AROUND 30-40 KT OF DEEP-LAYER SHEAR.  
SLOW-MOVING SUPERCELLS POSING A THREAT FOR LARGE TO VERY LARGE HAIL  
(2+ INCHES) SHOULD BE THE MAIN THREAT WITH INITIAL DEVELOPMENT. A  
TRANSITION TO ONE OR MORE BOWING CLUSTERS WITH A GREATER SEVERE WIND  
THREAT APPEARS POSSIBLE THROUGH THE EVENING AND OVERNIGHT HOURS AS  
CONVECTION SPREADS GENERALLY SOUTHEASTWARD TOWARD AND ACROSS  
SOUTH-CENTRAL/DEEP SOUTH TEXAS INCLUDING THE RIO GRANDE VICINITY.  
   
..CENTRAL/SOUTHERN HIGH PLAINS  
 
ON THE BACK SIDE OF AN UPPER TROUGH/LOW OVER THE NORTH-CENTRAL  
STATES, ISOLATED/HIGH-BASED THUNDERSTORMS SHOULD INITIALLY FORM OVER  
THE HIGHER TERRAIN THIS AFTERNOON BEFORE SPREADING SOUTHEASTWARD  
OVER THE ADJACENT HIGH PLAINS. WHILE INSTABILITY SHOULD TEND TO  
REMAIN FAIRLY WEAK, STEEPENED LOW-LEVEL LAPSE RATES THIS  
AFTERNOON/EVENING AND SUFFICIENT DEEP-LAYER SHEAR TO SUPPORT MODEST  
UPDRAFT ORGANIZATION MAY SUPPORT OCCASIONAL HAIL AND SEVERE WIND  
GUSTS.  
 
 
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