Damaging Wind in Virginia, June 4, 2001

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG, VA
1015 AM EDT MON JUN 4 2001

WILL UPDATE ZONES TO RAISE POPS FOR AT LEAST THE WRN HALF OF THE
CWA.  THUNDERSTORM COMPLEX OVER ERN KY IS ADVANCING EAST AND WILL
RESULT IN CATAGORICAL POPS FOR OUR WRN COUNTIES EARLY THIS
AFTERNOON...WITH LIKELY POPS FOR THE NRV.

A WARM FRONT WAS LOCATED W-E ACROSS SRN KY AND INTO NC THIS MORNING.
THIS FEATURE WILL BE THE FOCUS FOR REGENERATIVE MCS COMPLEX FEATURES
THE NEXT SEVERAL DAYS.  FLOW ALOFT SUPPORTS FAST MOVING BOW ECHO
TYPE DEEP CONVECTION.  PAST RAINFALL (6-8 INCHES ACROSS THE CWA THE
LAST 3 WEEKS) ALSO SUGGEST POTENTIAL FOR FLASH FLOODING.  WILL ISSUE
A SWO/SPS TO ADDRESS THESE CONCERNS. AN ESF MAY ALSO BE NEEDED TO
HEIGHTEN CONCERN FOR HEAVY RAIN THREAT AND POTENTIAL FOR RIVER
FLOODING.

GOOD DSCNS FROM BOTH SPC AND NESDIS THIS MORNING.  HERE THEY ARE FOR
YOUR PERUSAL.

SPC DSCN FOR THE LOWER OHIO VALLEY INTO NORTH CAROLINA...

ONGOING MCS FROM MISSOURI INTO KENTUCKY WILL LIKELY WEAKEN DURING
THE MORNING AS IT SHIFTS EAST OF LOW LEVEL JET AXIS.
HOWEVER...DIURNAL HEATING SHOULD DESTABILIZE AIRMASS SOUTH OF
OUTFLOW BOUNDARIES WITH THUNDERSTORMS DEVELOPING/INCREASING IN
INTENSITY BY THE EARLY AFTERNOON HOURS.  12Z OBSERVED 700-500 MB
WESTERLY FLOW OF 30-40 KNOTS AT BNA/GSO/MHX SUGGEST THAT BOW ECHOES
WITH DAMAGING WINDS AND LARGE HAIL WILL BE POSSIBLE DURING THE
AFTERNOON AND EARLY EVENING HOURS.

HEAVY RAINFALL DSCN FROM NESDIS...

SATELLITE ANALYSIS AND TRENDS...THE LATEST SAT IMAGERY INDICATES
COOLING CB TOPS ACROSS CENT AND ERN KY WITH VERY HVY RAINFALL RATES
NOW INDICATED. LATEST GOES-DPI PWS ARE NEAR 1.75 IN SRN KY AND THIS
SUPPORTS RAIN RATES THAT CAN EXCEED 3/HR GIVEN TOPS TO NR -70C.
EARLY VIS INDICATES A FEW OVERSHOOTING TOPS WHICH SUPPORTS RAIN
BURST ACTIVITY. SO VERY HVY RAINFALL AMTS ARE FEASIBLE IN A VERY
SHORT PERIOD OF TIME.

ON THE MESOSCALE...THE DEVELOPING CB TOPS ARE MERGING TO FORM AN MCS
WHICH ALL SEEMS TO BE THE RESULT OF A WEAK S/W IN THE WV IMAGERY
MOVING IN CENT KY. GIVEN THE FACT THERE IS A BAROCLINIC ZONE IN TN
AND NC AND A MODEST 850 LLJ ROLLING NWD ACROSS AHEAD OF THE WEAK
S/W....THE CURRENT COLD TOPS HAVE SUPPORT TO LAST THROUGH MUCH OF
THE MORNING AS THEY MOVE SEWD.

AREAS ACROSS ERN KY...SW VA AND NE TN IN GENERAL HAVE LOW FFG VALUES
AND WILL BE IN THE PATH OF THE MCS THIS MORNING. EXCESSIVE RAINFALL
AMTS SEEM PROBABLE AT LEAST ON A LOCAL BASIS DUE TO THE VERY HIGH PW
ENVIRONMENT.

.RNK...
NC...NONE.
VA...NONE.
WV...NONE.

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NCZ001>006-018-019-VAZ007-009>020-022>024-032>035-043>046-058-059-
WVZ042>045-042200-
SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BLACKSBURG VA
1208 PM EDT MON JUN 4 2001

...SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING...

THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS LATER TODAY.
ISOLATED SEVERE WEATHER IS POSSIBLE BETWEEN 4:00 PM AND MIDNIGHT.
THE MAIN THREAT IS DAMAGING WINDS.

THE GREATEST POTENTIAL FOR THUNDERSTORM DEVELOPMENT WILL BE ACROSS
AREAS SOUTH AND WEST OF ROANOKE VIRGINIA.  A WARM FRONT STRETCHES
FROM SOUTHERN KENTUCKY TO WESTERN NORTH CAROLINA...AND THIS WILL BE
THE FOCUS FOR THUNDERSTORM FORMATION THIS AFTERNOON.

SKYWARN ACTIVATION MAY BE REQUIRED IN NORTH CAROLINA...BUT IS NOT
ANTICIPATED FOR VIRGINIA.

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