206  
ACUS01 KWNS 301935  
SWODY1  
SPC AC 301934  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0234 PM CDT FRI SEP 30 2016  
 
VALID 302000Z - 011200Z  
 
...THERE IS A MRGL RISK OF SVR TSTMS ACROSS PORTIONS OF ERN  
INDIANA/OH/WRN WV...  
 
...THERE IS A MRGL RISK OF SVR TSTMS ACROSS PARTS OF SRN VA AND INTO  
NC/EXTREME NERN SC...  
   
..SUMMARY
 
 
A FEW STRONG TO LOCALLY SEVERE THUNDERSTORMS REMAIN POSSIBLE TODAY  
ACROSS PORTIONS OF VIRGINIA AND NORTH CAROLINA AS WELL AS THE OHIO  
RIVER VALLEY.  
   
..DISCUSSION
 
 
NO SUBSTANTIVE CHANGES ARE BEING MADE TO THE OUTLOOK ATTM...WITH  
ONLY MINOR LINE ADJUSTMENTS APPEARING NECESSARY. RISK FOR A SEVERE  
STORM OR TWO WILL LINGER INTO EARLY EVENING ACROSS PORTIONS OF  
WV/OH/INDIANA...AS WELL AS PORTIONS OF THE VA AND NC VICINITY.  
 
..GOSS.. 09/30/2016  
   
PREV DISCUSSION
 
/ISSUED 1129 AM CDT FRI SEP 30 2016/  
   
..NC THROUGH VA
 
 
AS OF MID DAY A QUASI-STATIONARY FRONT /PORTIONS OF WHICH HAVE BEEN  
CONVECTIVELY REINFORCED/ EXTENDS FROM NERN NC WSWWD TO A WEAK LOW  
PRESSURE AREA IN WRN NC. A COLD FRONT EXTENDS FROM ERN SC NWWD INTO  
CNTRL NC WHERE IT INTERSECTS THE STATIONARY FRONT. WIDESPREAD CLOUDS  
AND SCATTERED ONGOING STORMS CONTINUE THROUGH MUCH OF WARM  
SECTOR...BUT CLOUD BREAKS IN WAKE OF EARLY STORMS WILL RESULT IN AT  
LEAST MODEST BOUNDARY LAYER DESTABILIZATION...ESPECIALLY FROM NRN NC  
INTO A PORTION OF SRN VA. WEAK MID-LEVEL LAPSE RATES SHOULD LIMIT  
MLCAPE TO AOB 1500 J/KG WITH THE STRONGER INSTABILITY OVER ERN NC.  
STORMS DEVELOPING WITHIN AN ARC FROM ERN NC NWWD THROUGH WCNTRL VA  
WILL CONTINUE NWD INTO THE AFTERNOON. STRONGEST STORM WITH SUPERCELL  
STRUCTURES REMAINS OVER NCNTRL NC AND MAY CONTINUE TO POSE A  
SHORT-TERM THREAT FOR MAINLY HAIL AND STRONG WIND GUSTS...BUT A  
BRIEF TORNADO CANNOT BE RULED OUT.  
 
IN WAKE OF ONGOING ARC OF STORMS...ADDITIONAL CONVECTION MAY DEVELOP  
WHERE THE SFC-LAYER IS DESTABILIZING IN VICINITY OF A NW-SE ORIENTED  
OUTFLOW BOUNDARY ACROSS NWRN THROUGH CNTRL NC AND NWD INTO SCNTRL  
VA. HOWEVER...WV IMAGERY SHOWS A ZONE OF SIGNIFICANT DRYING ALOFT  
SPREADING NWD...AND THIS WAS SAMPLED BY THE 12Z GSO RAOB. WEAK  
MID-LEVEL LAPSE RATES AND SUBSTANTIAL DRY AIR ALOFT MAY TEND TO  
REDUCE UPDRAFT STRENGTH THROUGH ENTRAINMENT...LIMITING OVERALL  
SEVERE POTENTIAL. NEVERTHELESS...A CONDITIONAL RISK FOR FEW STRONG  
TO SEVERE STORMS WILL REMAIN POSSIBLE INTO THE AFTERNOON GIVEN 40+  
KT EFFECTIVE SHEAR AND VEERING LOW-LEVEL WIND PROFILES SUPPORTIVE OF  
UPDRAFT ROTATION.  
   
..OH VALLEY AREA
 
 
THUNDERSTORMS CONTINUE DEVELOPING IN AN ARC WITHIN UPPER LOW  
CIRCULATION ACROSS CNTRL OH. DIABATIC WARMING OF THE BOUNDARY LAYER  
WITHIN ZONE OF CLEARING IN VICINITY OF THE STORMS MAY RESULT IN SOME  
INTENSIFICATION DURING THE AFTERNOON. COOL TEMPERATURES ALOFT AND  
DIABATIC WARMING WILL CONTRIBUTE TO WEAK BUOYANCY WHERE EFFECTIVE  
SHEAR IS SUPPORTIVE OF A FEW STORMS TO DEVELOP UPDRAFT ROTATION  
WHICH MAY PROMOTE A THREAT FOR SMALL TO MARGINALLY SEVERE HAIL AND  
PERHAPS A BRIEF TORNADO.  
 

 
 
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