733  
ACUS01 KWNS 230558  
SWODY1  
SPC AC 230557  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1257 AM CDT SAT MAR 23 2019  
 
VALID 231200Z - 241200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL  
OK INTO NORTH-CENTRAL TX...  
   
..SUMMARY
 
 
ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS PORTIONS OF  
CENTRAL OKLAHOMA INTO NORTH-CENTRAL TEXAS LATE THIS AFTERNOON INTO  
EARLY EVENING. LARGE HAIL AND DAMAGING WIND WOULD BE THE PRIMARY  
THREAT WITH ANY SEVERE STORM THAT DEVELOPS.  
   
..SYNOPSIS
 
 
A MID/UPPER-LEVEL TROUGH WILL MOVE NORTHEASTWARD FROM THE  
CENTRAL/SOUTHERN PLAINS INTO THE UPPER MIDWEST TODAY INTO TONIGHT,  
AS AN UPSTREAM UPPER TROUGH MOVES INTO THE GREAT BASIN AND INTERIOR  
NORTHWEST. AT THE SURFACE, A WEAK CYCLONE WILL MOVE FROM THE CENTRAL  
HIGH PLAINS INTO THE UPPER MIDWEST BY SUNDAY MORNING, WHILE A LEE  
TROUGH/WEAK CYCLONE WILL PERSIST OVER THE SOUTHERN HIGH PLAINS AS  
MODERATE MIDLEVEL WESTERLY FLOW IS MAINTAINED OVER THE SOUTHERN  
ROCKIES.  
   
..CENTRAL/EASTERN OK...NORTH-CENTRAL/NORTHEAST TX
 
 
WEAK ELEVATED CONVECTION IS LIKELY TO BE ONGOING ACROSS OK AND NORTH  
TX THIS MORNING. THIS ACTIVITY MAY PERSIST ACROSS EASTERN  
OK/NORTHEAST TX INTO THE AFTERNOON, BUT THE I-35 CORRIDOR ACROSS  
OK/TX WILL LIKELY BEGIN TO CLEAR OUT BY MIDDAY DUE TO SUBSIDENCE IN  
THE WAKE OF THE MIDLEVEL TROUGH MOVING ACROSS KS. MODEST LOW-LEVEL  
MOISTURE RETURN TO THE EAST OF A WEAK PACIFIC COLD FRONT/EFFECTIVE  
DRYLINE WILL ALLOW FOR DEWPOINTS TO RISE INTO THE MID 50S ACROSS  
CENTRAL OK TO AROUND 60 INTO NORTH TX. IN CONJUNCTION WITH DIURNAL  
HEATING, THESE DEWPOINTS WILL BE SUFFICIENT TO SUPPORT MLCAPE OF  
500-1500 J/KG, GIVEN RELATIVELY COLD TEMPERATURES ALOFT (-15C TO  
-18C AT 500 MB). MODEST LOW-LEVEL SOUTH-SOUTHEASTERLY FLOW VEERING  
TO MODERATE WESTERLY FLOW ALOFT WILL SUPPORT EFFECTIVE SHEAR OF  
40-50 KT, SUFFICIENT TO SUPPORT A CONDITIONAL RISK OF ORGANIZED  
CONVECTION.  
 
A CONSIDERABLE AMOUNT OF UNCERTAINTY REMAINS REGARDING THE COVERAGE  
OF SURFACE-BASED CONVECTION ALONG/AHEAD OF THE DRYLINE LATE THIS  
AFTERNOON INTO THIS EVENING. LARGE-SCALE SUPPORT APPEARS NEUTRAL AT  
BEST, WITH LOW-LEVEL CONVERGENCE LIKELY TO BE MODEST ALONG THE  
DRYLINE. MOST HREF MEMBERS FAIL TO SUSTAIN SURFACE-BASED CONVECTION  
ALONG/AHEAD OF THE DRYLINE, BUT THE LATEST NAM/GFS/ECMWF CONTINUE TO  
GENERATE CONVECTIVE PRECIPITATION NEAR AND AFTER 00Z. GIVEN THE  
POTENTIAL FOR ISOLATED SUPERCELL DEVELOPMENT LATE THIS AFTERNOON OR  
EARLY EVENING ALONG OR JUST WEST OF THE I-35 CORRIDOR, A HIGHLY  
CONDITIONAL MARGINAL RISK FOR HAIL/WIND HAS BEEN INTRODUCED WITH  
THIS OUTLOOK.  
 
REGARDLESS OF DEVELOPMENT ALONG THE DRYLINE, THERE IS SOMEWHAT  
GREATER CONFIDENCE IN THE DEVELOPMENT OF ELEVATED CONVECTION TONIGHT  
ACROSS EASTERN OK INTO NORTHEAST TX, AS ISENTROPIC LIFT INCREASES IN  
RESPONSE TO A MODEST INTENSIFICATION OF THE LOW-LEVEL JET. ELEVATED  
BUOYANCY MAY BE SUFFICIENT TO SUPPORT SOME HAIL WITH THIS ACTIVITY,  
THOUGH STORMS LATE TONIGHT ACROSS THIS AREA ARE EXPECTED TO LARGELY  
REMAIN SUBSEVERE.  
   
..KS
 
 
A CONDITIONALLY FAVORABLE ENVIRONMENT FOR ORGANIZED CONVECTION WILL  
ALSO LIKELY DEVELOP INTO PORTIONS OF SOUTH-CENTRAL/SOUTHEAST KS,  
THOUGH WITH SIMILAR UNCERTAINTY REGARDING INITIATION AND LESS  
BUOYANCY COMPARED TO AREAS FURTHER SOUTH, THE MARGINAL HAS NOT BEEN  
EXTENDED INTO KS AT THIS TIME. FURTHER NORTH INTO NORTH-CENTRAL KS,  
STORM COVERAGE IS LIKELY TO BE GREATER IN CLOSER PROXIMITY TO THE  
MIDLEVEL LOW. WHILE BUOYANCY WILL WEAKER IN THIS AREA, COLD MIDLEVEL  
TEMPS MAY SUPPORT SOME HAIL RISK, AND A MARGINAL RISK MAY BE  
REQUIRED IF A MODEST AMOUNT OF DIURNAL HEATING APPEARS LIKELY THIS  
AFTERNOON.  
 
..DEAN/NAUSLAR.. 03/23/2019  
 

 
 
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