860  
ACUS01 KWNS 051632  
SWODY1  
SPC AC 051630  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1130 AM CDT THU JUN 05 2025  
 
VALID 051630Z - 061200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF  
THE SOUTHERN AND CENTRAL PLAINS...  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE  
NORTHEAST...  
   
..SUMMARY
 
 
SCATTERED SEVERE THUNDERSTORMS ARE EXPECTED ACROSS THE SOUTHERN AND  
CENTRAL PLAINS INTO TONIGHT. SEVERAL TORNADOES (SOME POSSIBLY  
STRONG), LARGE TO VERY LARGE HAIL, AND SEVERE GUSTS ARE POSSIBLE.  
SEVERE GUSTS ARE ALSO POSSIBLE OVER PARTS OF THE NORTHEAST THIS  
AFTERNOON.  
   
..SOUTHERN HIGH PLAINS
 
 
MORNING SURFACE ANALYSIS DEPICTS A CONVECTIVELY REINFORCED  
QUASI-STATIONARY SURFACE BOUNDARY EXTENDING ACROSS NORTH-CENTRAL TX  
WESTWARD THROUGH THE TX SOUTH PLAINS TO SOUTHEAST/EAST-CENTRAL NM.  
THIS BOUNDARY MAY HAVE A TENDENCY OF MOVING SLOWLY NORTHWARD AS A  
WARM FRONT OVER THE HIGH PLAINS LATER THIS AFTERNOON -- IN RESPONSE  
TO AN APPROACHING MIDLEVEL IMPULSE AND GRADUALLY DEEPENING LEE  
CYCLONE OVER SOUTHEAST CO. ALONG/IMMEDIATELY SOUTH OF THIS BOUNDARY  
(OVER THE TX SOUTH PLAINS), DEEP/RICH BOUNDARY-LAYER MOISTURE (UPPER  
60S/LOWER 70S DEWPOINTS) IS IN PLACE, WITH IMPRESSIVE MOISTURE  
SAMPLED BY THE 12Z MAF SOUNDING (15.8 G/KG MEAN MIXING RATIO).  
PERSISTENT CLOUD COVERAGE WILL TEND TO SHELTER THIS MOISTURE FROM  
DIURNALLY DRIVEN BOUNDARY-LAYER MIXING THROUGH THE AFTERNOON, WHILE  
HEATING IN CLOUD BREAKS WILL STILL YIELD STRONG SURFACE-BASED  
INSTABILITY (UPWARDS OF 3000 J/KG MLCAPE). AS A LOW-AMPLITUDE  
IMPULSE AND RELATED JET STREAK ADVANCE EAST-NORTHEASTWARD ACROSS THE  
CENTRAL HIGH PLAINS, PERIPHERAL LARGE-SCALE ASCENT WILL AID IN  
SCATTERED THUNDERSTORM DEVELOPMENT ACROSS EAST-CENTRAL/SOUTHEAST NM  
INTO THE TX SOUTH PLAINS -- FOCUSED NEAR THE INTERSECTION OF THE  
NORTHWARD-MOVING WARM FRONT AND LEE TROUGH. AROUND 50-60 KT OF  
EFFECTIVE SHEAR AND THE MODEST LARGE-SCALE ASCENT WILL FAVOR  
DISCRETE SUPERCELLS, INITIALLY POSING A RISK OF VERY LARGE HAIL.  
HOWEVER, A STRENGTHENING EVENING LOW-LEVEL JET ATOP THE BACKED  
LOW-LEVEL FLOW NEAR THE BOUNDARY WILL SUPPORT ENLARGING CLOCKWISE  
HODOGRAPHS (300+ M2/S2 EFFECTIVE SRH). GIVEN THE DEEP/RICH MOISTURE  
AND ENHANCED HELICITY, A FOCUSED CORRIDOR FOR TORNADOES (SOME  
POSSIBLY STRONG) IS EVIDENT OVER THE TX SOUTH PLAINS -- WHERE  
10-PERCENT TORNADO PROBABILITIES WERE ADDED. LOCALIZED UPSCALE  
GROWTH INTO ORGANIZED CLUSTERS IS EXPECTED INTO WESTERN NORTH TEXAS  
THIS EVENING, WHERE A SWATH OF SEVERE WIND IS POSSIBLE.  
 
FATHER SOUTH FROM THE TX SOUTH PLAINS TO PARTS OF THE TX TRANS-PECOS  
VICINITY, DEEP BOUNDARY-LAYER MIXING AMID LOWER/MIDDLE 60S DEWPOINTS  
WILL CONTRIBUTE TO MODERATE-STRONG SURFACE-BASED INSTABILITY, WITH A  
LONG (ALBEIT STRAIGHTER) HODOGRAPH AWAY FROM THE SURFACE BOUNDARY.  
THIS WILL ALSO SUPPORT INTENSE DISCRETE/SEMI-DISCRETE SUPERCELLS,  
THOUGH THE PRIMARY CONCERN HERE WILL BE VERY LARGE HAIL (POSSIBLY 3+  
INCHES).  
   
..CENTRAL HIGH PLAINS INTO THE SOUTHERN PLAINS
 
 
IN THE LEFT-EXIT REGION OF A 40-50-KT MIDLEVEL JET STREAK IMPINGING  
ON THE CENTRAL HIGH PLAINS, THUNDERSTORM DEVELOPMENT IS EXPECTED  
AHEAD OF A GRADUALLY DEEPENING LEE CYCLONE OVER SOUTHEASTERN CO THIS  
AFTERNOON. DIURNAL HEATING (WITHIN CLOUD BREAKS) OF A MOIST AIR MASS  
(LOWER 60S DEWPOINTS) WILL YIELD MODERATE SURFACE-BASED INSTABILITY  
AHEAD OF DEVELOPING STORMS. GIVEN AROUND 50 KT OF EFFECTIVE SHEAR  
(CHARACTERIZED BY A LONG/GENERALLY STRAIGHT HODOGRAPH), SEVERAL  
SEMI-DISCRETE SUPERCELL CLUSTERS ARE EXPECTED. LARGE HAIL AND SEVERE  
WIND GUSTS ARE EXPECTED, THOUGH THE RICH/SHELTERED BOUNDARY-LAYER  
MOISTURE AND SUFFICIENT LOW-LEVEL STREAMWISE VORTICITY FOR  
ESTABLISHED RIGHT-MOVER CELLS WILL SUPPORT A COUPLE TORNADOES AS  
WELL. WITH TIME, STORMS WILL SPREAD EAST-SOUTHEASTWARD INTO  
NORTHWEST OK -- WHERE UPSCALE GROWTH INTO AN MCS SEEMS INCREASINGLY  
LIKELY. THIS WILL FAVOR AN INCREASED RISK OF A SWATH OF SEVERE WIND  
GUSTS INTO THE OVERNIGHT HOURS.  
   
..NORTHEAST
 
 
WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED ALONG/AHEAD OF A COLD  
FRONT DRAPED ACROSS THE REGION THIS AFTERNOON. VISIBLE SATELLITE  
IMAGERY SHOWS A MOIST/DESTABILIZING AIR MASS AHEAD OF THE FRONT,  
WHERE MODERATE SURFACE-BASED INSTABILITY IS EXPECTED. THE WARM/MOIST  
AIR MASS, COMBINED WITH AROUND 30 KT OF EFFECTIVE SHEAR, SHOULD  
PROMOTE A FEW LOOSELY ORGANIZED CLUSTERS CAPABLE OF PRODUCING WIND  
DAMAGE -- AIDED BY THE STEEPENING BOUNDARY-LAYER LAPSE RATES.  
 
..WEINMAN/SMITH.. 06/05/2025  
 

 
 
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