Severe Thunderstorm Warning 34, NWS Raleigh, NC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
245 PM EDT MON MAY 21 2001

ETA/AVN DEPICTING GOOD AGREEMENT WITH EACH OTHER CONCERNING TIMING
OF FRONTAL PASSAGE TUE WHILE NGM IS THE SLOWEST. MODELS ALSO
DISPLAYING FAIRLY GOOD RUN-TO-RUN CONTINUITY.

CLOUDS HAVE HUNG TOUGH THUS FAR ACROSS CENTRAL NC WITH MORE
PROMINENT BREAKS OCCURRING IN SC.  INFRA RED SATELLITE LOOP DEPICTS
MINOR UPPER LEVEL DISTURBANCE MOVING NORTHEAST OUT OF TN VALLEY
TOWARD NORTHERN MID ATLANTIC. THIS FEATURE HELPING TO
TRIGGER/SUSTAIN CONVECTION SW OF CENTRAL NC. AS THIS FEATURE
CONTINUES TO LIFT NE...EXPECT TO SEE CONVECTIVE COVERAGE
INCREASE...ESPECIALLY OVER NW PIEDMONT.

ETA 300MB DIVERGENCE PATTERN ALIGNS WELL WITH CONVECTION OCCURRING
AT 12Z AND VERIFIED WELL WITH EASTERN U.S. CONVECTION AT 18Z. IN
ADDITION ...LOW LEVEL SURFACE PARAMETERS HAS THETA-E
MAXIMUMINSTABILITY AXIS ALIGNED W-E ACROSS SOUTHERN
PIEDMONT/SANDHILLS. ETA DEPICTS SMALL AREA OF DIFFLUENCE ALOFT OVER
AREA AT 06Z...AND WITH FAVORABLE SURFACE PARAMETERS IN
PLACE...BELIEVE THAT CONVECTION MAY LINGER/DEVELOP PAST SUNSET
ACROSS CENTRAL NC.

ON TUE...FRONTAL PASSING REGION DURING PRIME HEATING. WITH AIR MASS
SUFFICIENTLY MOIST AND RATHER DEEP 35-40 KNOT WIND FILED OVER
REGION. GOOD POTENTIAL FOR T-STORMS. WIND PROFILE SUGGEST THAT
STORMS MAY FORM INTO BOW ECHOES THUS DAMAGING WINDS WILL BE THE
SEVERE WEATHER THREAT.  MAY ISSUE SWO WITH THIS PACKAGE TO HEIGHTEN
AWARENESS.

DRIER AIR ADVECTS INTO REGION TUE NIGHT...SETTING UP FOR NICE
WEATHER WED.  MAY SUNSHINE AND WEST-SW LOW LEVEL FLOW SUGGEST HIGH
TEMPS NEAR OR SLIGHTLY ABOVE GUIDANCE.

.EXTENDED FORECAST...UNSETTLED AND COOL WEATHER FOR THE PERIOD. NO
INTERNET SO UNABLE TO INTERROGATE MEDIUM RANGE MODELS.
UPPER CUT-OFF LOW REMAINS OVER EASTERN CONUS SLOWLY MOVING EAST.
MODEL TRENDS THIS RUN SLOWER THAN PREVIOUS RUN AS UPPER RIDGE REMAINS
OVER WEST COAST...NOT MUCH FORCING TO PUSH UPPER LOW EAST. EXPECT
SEVERAL S/WS TO ROTATE ACROSS CWA...EAST SIDE OF UPPER LOW AS IT
PROGRESSES SLOWLY EAST. AT THE SURFACE...HIGH CENTERED OVER NEW ENGLAND
NOSING INTO NCAROLINA DURING THURSDAY (WEDGE-LIKE FEATURE) AS ASSOCIATED
FRONT MOVES EAST INTO TENNESSEE VALLEY LATE THURSDAY...MOVING INTO THE
CWA ON FRIDAY. FRONTAL BOUNDARY LINGERS THROUGH SATURDAY. AVN A BIT
FASTER THAN LAST NIGHTS MRF AS IT MOVES FRONT EAST OF AREA 12Z
SATURDAY. SO WILL MENTION CHANCE FOR SHOWERS MAINLY IN THE AFTERNOON
THURSDAY. CHANCE FRIDAY AND SATURDAY. ANOTHER BOUNDARY CROSSES THE
AREA SUNDAY (PER LAST NIGHTS MRF) BUT MOISTURE LIMITED. SO WILL GO
PARTLY CLOUDY FOR SUNDAY AND MONDAY. TEMPERATURES WILL BE UNSEASONABLY
COOL MUCH OF THE PERIOD.

RDU 68/83/60/79 4710                     GSO 68/78/55/76 57-0
                     FAY 70/86/63/80 4730

.RAH...NONE.

WSS/RA

NCZ007>011-021>028-038>043-073>078-083>086-088-089-220915-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RALEIGH NC
420 PM EDT MON MAY 21 2001

ALAMANCE-ANSON-CHATHAM-CUMBERLAND-DAVIDSON-DURHAM-EDGECOMBE-FORSYTH-
FRANKLIN-GRANVILLE-GUILFORD-HALIFAX-HARNETT-HOKE-JOHNSTON-LEE-
MONTGOMERY-MOORE-NASH-ORANGE-PERSON-RANDOLPH-RICHMOND-SAMPSON-
SCOTLAND-STANLY-VANCE-WAKE-WARREN-WAYNE-WILSON-

...RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL NORTH CAROLINA
TUESDAY...

.SKYWARN SPOTTERS...
SKYWARN ACTIVATION MAY BE REQUIRED ACROSS THE TRIAD REGION BY
MID-DAY...AND IN THE TRIANGLE AND SANDHILLS REGIONS TUESDAY
AFTERNOON.  SPOTTERS ARE ENCOURAGED TO REPORT THREATENING WEATHER OF
ANY KIND TO THE NATIONAL WEATHER SERVICE.

.SYNOPTIC PATTERN...
A STRONG COLD FRONT WILL CROSS CENTRAL NORTH CAROLINA TUESDAY
AFTERNOON. A VERY MOIST AND UNSTABLE AIR MASS WILL SUPPORT THE
DEVELOPMENT OF THUNDERSTORMS AHEAD OF THE FRONT.

.HAZARDOUS WEATHER DETAILS...
THE PRIMARY SEVERE WEATHER THREAT FROM THE STORMS WILL BE DAMAGING
WINDS.  THE THREAT FOR SEVERE THUNDERSTORMS COULD REACH THE TRIAD
REGION AS WELL AS AREAS AROUND WADESBORO AND ASHEBORO BY 12 NOON.
FOR AREAS AROUND THE TRIANGLE AND THE SANDHILLS...THE THREAT FOR
SEVERE STORMS WILL BE GREATEST DURING THE EARLY AND MID AFTERNOON
HOURS. FOR LOCATIONS IN THE COASTAL PLAIN INCLUDING ROCKY MOUNT
...WILSON AND GOLDSBORO...THE THREAT OF SEVERE STORMS SHOULD HOLD
OFF UNTIL LATE AFTERNOON.  MOST OF THE STORMS SHOULD BE EAST OF
CENTRAL NORTH CAROLINA BY SUNSET.

STAY TUNED TO NOAA WEATHER RADIO FOR ADDITIONAL STATEMENTS.

WSS

NCZ007>011-021>028-038>043-073>078-083>086-088-089-220915-

SEVERE WEATHER OUTLOOK FOR CENTRAL NORTH CAROLINA...CORRECTION TO
TITLE
NATIONAL WEATHER SERVICE RALEIGH NC
420 PM EDT MON MAY 21 2001

ALAMANCE-ANSON-CHATHAM-CUMBERLAND-DAVIDSON-DURHAM-EDGECOMBE-FORSYTH-
FRANKLIN-GRANVILLE-GUILFORD-HALIFAX-HARNETT-HOKE-JOHNSTON-LEE-
MONTGOMERY-MOORE-NASH-ORANGE-PERSON-RANDOLPH-RICHMOND-SAMPSON-
SCOTLAND-STANLY-VANCE-WAKE-WARREN-WAYNE-WILSON-

...RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL NORTH CAROLINA
TUESDAY...

.SKYWARN SPOTTERS...
SKYWARN ACTIVATION MAY BE REQUIRED ACROSS THE TRIAD REGION BY
MID-DAY...AND IN THE TRIANGLE AND SANDHILLS REGIONS TUESDAY
AFTERNOON.  SPOTTERS ARE ENCOURAGED TO REPORT THREATENING WEATHER OF
ANY KIND TO THE NATIONAL WEATHER SERVICE.

.SYNOPTIC PATTERN...
A STRONG COLD FRONT WILL CROSS CENTRAL NORTH CAROLINA TUESDAY
AFTERNOON. A VERY MOIST AND UNSTABLE AIR MASS WILL SUPPORT THE
DEVELOPMENT OF THUNDERSTORMS AHEAD OF THE FRONT.

.HAZARDOUS WEATHER DETAILS...
THE PRIMARY SEVERE WEATHER THREAT FROM THE STORMS WILL BE DAMAGING
WINDS.  THE THREAT FOR SEVERE THUNDERSTORMS COULD REACH THE TRIAD
REGION AS WELL AS AREAS AROUND WADESBORO AND ASHEBORO BY 12 NOON.
FOR AREAS AROUND THE TRIANGLE AND THE SANDHILLS...THE THREAT FOR
SEVERE STORMS WILL BE GREATEST DURING THE EARLY AND MID AFTERNOON
HOURS. FOR LOCATIONS IN THE COASTAL PLAIN INCLUDING ROCKY MOUNT
...WILSON AND GOLDSBORO...THE THREAT OF SEVERE STORMS SHOULD HOLD
OFF UNTIL LATE AFTERNOON.  MOST OF THE STORMS SHOULD BE EAST OF
CENTRAL NORTH CAROLINA BY SUNSET.

STAY TUNED TO NOAA WEATHER RADIO FOR ADDITIONAL STATEMENTS.

WSS