141  
ACUS02 KWNS 170603  
SWODY2  
SPC AC 170602  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0102 AM CDT SAT MAY 17 2025  
 
VALID 181200Z - 191200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS NORTHERN  
OKLAHOMA AND MUCH OF CENTRAL AND EASTERN KANSAS...  
   
..SUMMARY  
 
SEVERE THUNDERSTORMS CAPABLE OF ALL SEVERE HAZARDS ARE EXPECTED ON  
SUNDAY ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS.  
   
..SYNOPSIS  
 
A MID-LEVEL SHORTWAVE TROUGH WILL MOVE FROM THE SOUTHWEST INTO THE  
CENTRAL PLAINS ON SUNDAY AS THE BROADER TROUGH DEVELOPS ACROSS THE  
INTERMOUNTAIN WEST. BY 00Z MONDAY, A ~992MB LEE CYCLONE WILL DEVELOP  
ALONG THE KS/CO BORDER. A WARM FRONT WILL EXTEND FROM THIS SURFACE  
LOW INTO NORTHERN KANSAS/SOUTHERN NEBRASKA BY SUNDAY EVENING AND  
WILL REMAIN MOSTLY STATIONARY ACROSS THE SOUTHEAST. A DRYLINE WILL  
EXTEND FROM CENTRAL KANSAS TO THE SOUTHERN PLAINS.  
   
..KANSAS AND NORTHERN OKLAHOMA  
 
A VERY MOIST AIRMASS WILL BE IN PLACE EAST OF THE DRYLINE ON SUNDAY  
WITH LOW 70S DEWPOINTS FORECAST ACROSS MUCH OF TEXAS, OKLAHOMA, AND  
SOUTHERN KANSAS AHEAD OF THE SURFACE BOUNDARY. AS TEMPERATURES WARM,  
STRONG TO VERY STRONG INSTABILITY IS FORECAST TO DEVELOP. AS THE  
MID-LEVEL SHORTWAVE TROUGH EMERGES ACROSS THE PLAINS, SYNOPTIC-SCALE  
ASCENT WILL COMBINE WITH THE INCREASING INSTABILITY TO DECREASE  
INHIBITION ACROSS MUCH OF THE DRYLINE. FORECAST GUIDANCE SHOWS  
LIMITED CONVERGENCE ALONG THE DRYLINE IN OKLAHOMA AND TEXAS DURING  
THE DAY SUNDAY WITH THE BETTER CONVERGENCE FOCUSED ACROSS KANSAS.  
THEREFORE, CONFIDENCE IS HIGHER FOR STORMS ACROSS CENTRAL AND  
SOUTHERN KANSAS AND PERHAPS INTO NORTHERN OKLAHOMA.  
 
ANY STORMS WHICH DEVELOP WILL BE SUPERCELLULAR WITH A THREAT FOR  
VERY LARGE HAIL AND TORNADOES, PARTICULARLY BY LATER IN THE EVENING  
AS THE LOW-LEVEL JET STRENGTHENS. WHILE CONFIDENCE IS HIGHER IN  
STORMS ACROSS THE ENHANCED RISK AREA, STORM EVOLUTION REMAINS  
UNCLEAR. 00Z CAM GUIDANCE HAS WIDE VARIATIONS IN THE NORTHEASTWARD  
PROGRESSION OF THE SURFACE WARM FRONT WHICH WILL SIGNIFICANTLY  
IMPACT STORM DEVELOPMENT ON SUNDAY. A MORE DISCRETE STORM MODE WOULD  
LIKELY POSE A GREATER VERY LARGE HAIL AND TORNADO THREAT, WHILE MORE  
WIDESPREAD STORM DEVELOPMENT WOULD LIKELY FAVOR DEVELOPMENT INTO A  
MCS WHICH COULD POSE A GREATER SEVERE WIND THREAT ACROSS EASTERN  
KANSAS AND INTO MISSOURI.  
 
DESPITE THE UNCERTAINTIES, THE ENHANCED (LEVEL 3 OF 5) RISK SEEMS  
APPROPRIATELY PLACED WHERE SEVERE STORMS ARE MOST LIKELY. THE 10%  
TORNADO PROBABILITIES DO NOT EXTEND TO THE NORTHERN EXTENT OF THE  
ENHANCED DUE TO THE AFOREMENTIONED UNCERTAINTIES IN THE WARM FRONTAL  
POSITION. HOWEVER, ELEVATED HAIL WILL REMAIN A THREAT NORTH OF THE  
WARM FRONT.  
   
..OKLAHOMA/TEXAS  
 
A DRYLINE WILL BE IN PLACE ACROSS WESTERN OKLAHOMA AND NORTH TEXAS  
FOR MUCH OF THE DAY SUNDAY. CONVERGENCE WILL BE MOSTLY WEAK ALONG  
THE OKLAHOMA DRYLINE FOR MUCH OF THE DAY WITH BETTER CONVERGENCE  
FARTHER SOUTH IN TEXAS, FARTHER FROM THE BETTER UPPER-LEVEL FORCING.  
HOWEVER, BY THE EVENING, CONVERGENCE WILL INCREASE SOMEWHAT WHICH  
COULD RESULT IN ISOLATED SUPERCELL DEVELOPMENT AS THE LOW-LEVEL JET  
INTENSIFIES DURING THE EVENING. THE ENVIRONMENT ACROSS OKLAHOMA AND  
NORTH TEXAS WILL BE VERY VOLATILE WITH A CONDITIONAL THREAT FOR  
INTENSE SUPERCELLS CAPABLE OF VERY LARGE HAIL AND STRONG TORNADOES.  
   
..NORTHEAST CO/SOUTHWEST NEBRASKA VICINITY  
 
BY SUNDAY AFTERNOON, LOW TO MID 60S DEWPOINTS WILL ADVECT WESTWARD  
AROUND THE SURFACE LOW INTO NORTHWEST KANSAS, NORTHEAST COLORADO,  
AND SOUTHWEST NEBRASKA. MODERATE TO STRONG INSTABILITY IS FORECAST  
AHEAD OF THE DRYLINE WHICH WILL AID IN SUPERCELL DEVELOPMENT BY THE  
AFTERNOON. A NARROW CORRIDOR OF INSTABILITY WILL BE THE PRIMARY  
LIMITING FACTOR TO THE TORNADO THREAT IN AN OTHERWISE VERY FAVORABLE  
STP ENVIRONMENT. IT APPEARS SUPERCELLS WILL LIKELY BE NORTH OF THE  
BOUNDARY BEFORE MATURING WHICH WILL SUPPORT A PRIMARY THREAT FOR  
LARGE HAIL. HOWEVER, IF A STORM CAN RAPIDLY MATURE AS IT DEVELOPS  
OFF THE DRYLINE, IT COULD POSE A TORNADO THREAT GIVEN THE FAVORABLE  
LOW-LEVEL SHEAR ACROSS THE REGION.  
   
..MID MISSISSIPPI VALLEY TO THE SOUTHEAST  
 
ISOLATED THUNDERSTORMS ARE POSSIBLE ALONG A STALLED FRONTAL ZONE  
THAT WILL EXTEND FROM THE MID-MISSISSIPPI VALLEY TO THE SOUTHEAST.  
MODERATE TO STRONG INSTABILITY WILL BE IN PLACE WITHIN A MODERATELY  
SHEARED ENVIRONMENT. FORCING WILL BE WEAK ALONG THE FRONT WITH  
NEUTRAL TO PERHAPS SLIGHTLY RISING HEIGHTS ALOFT. HOWEVER, FORECAST  
SOUNDINGS SHOW MINIMAL INHIBITION AND THEREFORE, ISOLATED  
DEVELOPMENT IS POSSIBLE. A GREATER SEVERE THREAT COULD MATERIALIZE  
FROM A REMNANT MCV/MCS WHICH WILL LIKELY EVOLVE FROM DAY 1/SATURDAY  
CONVECTION ACROSS NORTH TEXAS. IF THIS MAINTAINS ALONG THE FRONTAL  
ZONE INTO THE LATE MORNING ON SUNDAY, IT COULD PROVIDE A FOCUSED  
REGION OF GREATER SEVERE WEATHER THREAT SUNDAY AFTERNOON ACROSS  
AL/GA.  
 
..BENTLEY.. 05/17/2025  
 
 
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