Severe Thunderstorm Warning 46, NWS Raleigh, NC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
230 PM EDT FRI APR 7 2006

.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...

GFS APPEARS TO BE HANDLING CONVECTION ACROSS WESTERN SECTIONS OF
TN/KY BETTER THAN NAM AT 18Z. EXTRAPOLATION OF MODEL SUGGEST
CONVECTION THREAT INCREASING ACROSS NW SECTIONS OF CENTRAL NC AFTER
06Z. THUS DELAYED POP INITIATION A FEW HOURS FROM PREVIOUS FORECAST.
OTHERWISE EXPECT MILD AND BREEZY CONDITIONS OVERNIGHT.

SATURDAY...A LINE OF CONVECTIVE SHOWERS IS EXPECTED TO CROSS THE
MOUNTAINS NEAR DAYBREAK...AND WILL CONTINUE EAST DURING THE LATE
MORNING...EARLY AFTERNOON HOURS. INITIALLY...INSTABILITY WILL BE
LIMITED ACROSS THE WESTERN CWA DUE TO TIMING...HOWEVER RR QUAD
DIVERGENCE REGION...INCREASING PVA...AND 850 JET WILL SUSTAIN
WIDESPREAD SHOWERS WITH SCATTERED THUNDER. FURTHER DESTABILIZATION
IS EXPECTED WITH THE LINE OF CONVECTION  BECOME BETTER ORGANIZED
FROM 15-18Z AS THE LINE MOVES EAST INTO THE CENTRAL PIEDMONT AND
COASTAL PLAIN REGION AND ENCOUNTERS HIGHER DEWPOINT AIR.
SBCAPE OF 1500-2000 J/KG...50-65KT 0-6KM DEEP SHEAR...AND
MID-LEVEL LAPSE RATES 6 TO 7...WILL SUPPORT STRONG UPDRAFTS CAPABLE
OF PRODUCING LARGE HAIL (WET BULB  9.5-10.3KFT) AND DAMAGING WIND
GUSTS. SPCS CURRENT SLIGHT RISK OUTLOOK AREAS ALONG AND EAST OF
I-95 LINES UP WELL WITH ABOVE PARAMETERS. TORNADO RISK APPEARS
MINIMAL...HOWEVER LOW-LEVEL SHEAR/HELICITY COULD BE ENHANCED BY THE
DEVELOPMENT OF A MESO-LOW THAT BOTH THE GFS/NAM ARE INDICATING WILL
DEVELOP. STORMS SHOULD BE EXITING THE EASTERN CWA BY 21Z WITH
RESIDUAL SHOWERS ENDING WEST TO EAST BY 03Z. WILL CONTINUE TREND OF
MOST HIGHS TO OCCUR EARLY IN THE DAY. GRADUAL CLEARING FROM WEST TO
EAST OVERNIGHT WITH LOWS 40 TO 45.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...

MODERATING AIRMASS THROUGH THE PERIOD AS CANADIAN HIGH BUILDS OVER
THE MID ATLANTIC REGION AND THEN OFF THE EAST COAST BY MIDWEEK. NO
SIGNIFICANT RAINFALL EXPECTED WITH LATE WEDNESDAY/EARLY THURSDAY
SYSTEM WITH ABSENCE OF GULF OR ATLANTIC MOISTURE FEED AND DYNAMICS
CONFINED TO THE NORTH. WARMER THURSDAY AND FRIDAY AS AMPLIFYING MID
AND UPPER RIDGE BUILDS OVER THE EASTERN SEABOARD.

&&

.AVIATION...

VFR CONDITIONS THROUGH 10Z AS CEILINGS REMAIN AOA 8K FT AND
VISIBILITY IS UNRESTRICTED. LOW LEVEL AIRMASS WILL REMAIN WELL MIXED
WITH SUSTAINED S-SW WIND 15-20KTS THROUGH EARLY EVENING...GRADUALLY
DECREASING TO 10-15KTS AFTER 01Z.

APPROACHING COLD FRONT WILL INCREASE THREAT FOR CONVECTION ACROSS
THE INT/GSO TERMINALS BY 10Z...AND ACROSS RDU TERMINAL BY 14Z.
CONVECTION WILL LIKELY HOLD OFF AT FAY AND RWI UNTIL 16Z.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

SHORT TERM...LOCKLEAR/WSS
LONG TERM...LOCKLEAR
AVIATION...WSS