440  
ACUS02 KWNS 221731  
SWODY2  
SPC AC 221730  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1230 PM CDT THU AUG 22 2019  
 
VALID 231200Z - 241200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS  
OF SOUTHERN VIRGINIA AND NORTH CAROLINA...AND OVER PARTS OF THE  
NORTHERN AND CENTRAL HIGH PLAINS...  
   
..SUMMARY
 
 
ISOLATED/LOCAL WIND GUSTS POSSIBLY REACHING SEVERE LEVELS ARE  
POSSIBLE FRIDAY OVER PARTS OF NORTH CAROLINA AND SOUTHERN VIRGINIA,  
WHILE A LIMITED RISK FOR HAIL AND LOCALIZED STRONG GUSTS WILL ALSO  
BE POSSIBLE OVER THE NORTHERN AND CENTRAL HIGH PLAINS.  
   
..SYNOPSIS
 
 
AS AN UPPER TROUGH PROGRESSES ACROSS EASTERN CANADA AND THE  
NORTHEASTERN U.S. FRIDAY, AN ASSOCIATED/SURFACE COLD FRONT IS  
EXPECTED TO HAVE CLEARED THE NEW ENGLAND AND MID ATLANTIC COASTS BY  
THE START OF THE PERIOD. THE TRAILING PORTION OF THIS BOUNDARY,  
ARCING FROM VIRGINIA WESTWARD ACROSS THE MID SOUTH, INTO THE  
SOUTHERN PLAINS, AND THEN NORTHWESTWARD ACROSS THE CENTRAL AND  
NORTHERN HIGH PLAINS, WILL MAKE GRADUAL SOUTHWARD PROGRESS OVER THE  
EASTERN HALF OF THE COUNTRY.  
 
MEANWHILE, A SECOND/WEAKER TROUGH IS FORECAST TO CROSS THE ROCKIES,  
REACHING THE PLAINS STATES LATE. IN CONJUNCTION WITH THIS TROUGH, A  
COLD FRONT WILL CONTINUE CROSSING THE NORTHERN INTERMOUNTAIN REGION  
AND WILL EVENTUALLY REACH THE HIGH PLAINS, INTERSECTING THE  
PRIOR/REMNANT FRONT LINGERING IN LEE OF THE MOUNTAINS.  
   
..SOUTHERN VIRGINIA/NORTH CAROLINA
 
 
AFTERNOON THUNDERSTORM DEVELOPMENT IS EXPECTED FROM THE  
VIRGINIA/NORTH CAROLINA REGION WESTWARD ACROSS THE MID SOUTH/MID  
MISSISSIPPI VALLEY AREA, AS DIURNAL DESTABILIZATION OCCURS.  
ALTHOUGH A LOCAL/PULSE-TYPE SEVERE RISK MAY OCCUR WITH A FEW MORE  
INTENSE UPDRAFTS ALONG THE ENTIRE FRONTAL ZONE, WEAK SHEAR SHOULD  
HINDER UPDRAFT ORGANIZATION IN MOST AREAS.  
 
ONE AREA OF SLIGHTLY GREATER RISK -- COINCIDENT WITH SLIGHTLY  
GREATER FLOW ALOFT LINGERING ONSHORE ON THE SOUTHERN PERIPHERY OF  
THE DEPARTING UPPER SYSTEM -- IS APPARENT OVER PORTIONS OF VIRGINIA  
AND NORTH CAROLINA. HERE, MODERATE MID-LEVEL WESTERLIES MAY PROMOTE  
SLIGHTLY MORE ORGANIZED, EASTWARD-MOVING STORMS/STORM CLUSTERS, AND  
THUS SLIGHTLY GREATER SEVERE RISK AS COMPARED TO OTHER AREAS WITHIN  
THE REMNANT FRONTAL ZONE. RISK SHOULD DIMINISH DURING THE EVENING,  
AS THE AIRMASS STABILIZES DIURNALLY.  
   
..NORTHERN AND CENTRAL HIGH PLAINS
 
 
AFTERNOON STORM DEVELOPMENT IS EXPECTED -- INITIALLY OVER THE  
EASTERN WYOMING VICINITY, NEAR THE INTERSECTION OF A COLD FRONT  
CROSSING THE NORTHERN INTERMOUNTAIN REGION AND THE REMNANT FRONT/LEE  
TROUGH OVER THE HIGH PLAINS. WITH MODERATE CAPE EXPECTED TO EVOLVE  
(2000 TO 3000 J/KG ACROSS THE REGION), A FEW STRONGER STORMS -- AND  
SOME UPSCALE CLUSTERING -- IS EXPECTED. HOWEVER, SOMEWHAT LIMITED  
WESTERLY FLOW ALOFT SUGGESTS MARGINAL SHEAR IN MOST AREAS. WITH  
LOW-LEVEL SOUTHEASTERLIES EXPECTED ACROSS THE PLAINS HOWEVER, SHEAR  
MAY PROVE SUFFICIENT -- BENEATH A SMALL, SLIGHTLY ENHANCED BELT OF  
WESTERLIES INDICATED OVER THE WYOMING VICINITY -- FOR DEVELOPMENT OF  
A COUPLE OF SUPERCELLS INITIALLY, THEN POSSIBLY GROWING INTO A  
CLUSTER OF STORMS THAT MAY SHIFT OFF THE HIGHER TERRAIN. AS SUCH,  
LOCAL HAIL/WIND RISK WARRANTS CONTINUATION OF MRGL RISK, WITH SOME  
CHANCE THAT A SMALL SLGT RISK COULD BE ADDED IN FUTURE OUTLOOK  
UPDATES.  
   
..MAXIMUM RISK BY HAZARD
 
 
TORNADO: 2% - MARGINAL  
WIND: 5% - MARGINAL  
HAIL: 5% - MARGINAL  
 
..GOSS.. 08/22/2019  
 

 
 
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