[MCD] SWOMCD

Mon Apr 3 18:38:18 UTC 2006

ACUS11 KWNS 031836
SWOMCD
SPC MCD 031836 
NCZ000-VAZ000-032030-

MESOSCALE DISCUSSION 0421
NWS STORM PREDICTION CENTER NORMAN OK
0136 PM CDT MON APR 03 2006

AREAS AFFECTED...SRN VA...NRN NC

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 031836Z - 032030Z

STORM INITIATION WILL BECOME INCREASINGLY LIKELY FROM NRN NC INTO
SRN VA AS DESTABILIZATION OCCURS THIS AFTERNOON. THE ENVIRONMENT
WILL BECOME FAVORABLE FOR SUPERCELLS WITH A POTENTIAL FOR
TORNADOES...LARGE HAIL AND WIND DAMAGE. A WW MAY BE NEEDED BY MID TO
LATE AFTERNOON ACROSS THE REGION.

WATER VAPOR IMAGERY CURRENTLY SHOWS A STRONG UPPER-LEVEL TROUGH
ENTERING THE APPALACHIAN MTNS. LARGE-SCALE ASCENT WILL MARKEDLY
INCREASE AS THE TROUGH BEGINS TO AFFECT THE FOOTHILLS OF VA AND NC
THIS AFTERNOON. IN ADDITION...VISIBLE IMAGERY SHOWS CUMULUS
BEGINNING TO FORM ALONG A MESOSCALE THERMAL AXIS EXTENDING NWD FROM
GREENSBORO NC TO ROANOKE VA. ALTHOUGH THE AREA REMAINS CAPPED AND
WEAKLY UNSTABLE...DESTABILIZATION WILL CONTINUE DUE TO SFC HEATING.
IN ADDITION...LOW-LEVEL CONVERGENCE SHOULD BECOME ENHANCED LATE THIS
AFTERNOON WHICH COMBINED INCREASING ASCENT FROM THE WEST SHOULD
SUPPORT STORM INITIATION. INITIATION WOULD BE MOST LIKELY ALONG THE
THERMAL AXIS IN THE 20Z TO 22Z TIMEFRAME.

CLEARING ON VISIBLE IMAGERY SHOULD ALLOW MODERATE INSTABILITY TO
DEVELOP BY LATE AFTERNOON WHICH COMBINED WITH 50 KT OF VERTICAL
SHEAR WILL BE FAVORABLE FOR SUPERCELLS. IN ADDITION...A 40 KT
LOW-LEVEL JET CURRENTLY FORMING OVER NRN NC EVIDENT ON OBJECTIVE
ANALYSIS COMBINED WITH BACKED SFC WINDS ALONG THE NC-VA STATE-LINE
WILL BE INCREASINGLY FAVORABLE FOR TORNADOES AS SUPERCELLS DEVELOP
AND TRACK EWD INTO SE VA AND NE NC BY EARLY THIS EVENING. LARGE HAIL
AND WIND DAMAGE WILL ALSO BE LIKELY WITH SUPERCELLS AS LAPSE RATES
STEEPEN DUE TO THE APPROACH OF THE UPPER-LEVEL TROUGH.

..BROYLES.. 04/03/2006

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...AKQ...MHX...LWX...RAH...RNK...GSP...

35347698 35117848 35227996 35768049 36148061 36778064
37198032 37557918 37557731 37377641 36837607 36217602
35727610 