Severe Thunderstorm Warning 102, NWS Greenville-Spartanburg, SC

704 
WWUS52 KGSP 262213
SVSGSP

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
613 PM EDT TUE APR 26 2011

NCC025-119-179-262223-
/O.CAN.KGSP.SV.W.0102.000000T0000Z-110426T2245Z/
CABARRUS NC-MECKLENBURG NC-UNION NC-
613 PM EDT TUE APR 26 2011

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN UNION...EASTERN
MECKLENBURG AND CABARRUS COUNTIES IN THE PIEDMONT OF NORTH CAROLINA
IS CANCELLED...

THE STORM HAS WEAKENED BELOW SEVERE LEVELS. 

LAT...LON 3519 8050 3516 8044 3487 8060 3493 8079
      3495 8080 3551 8074 3545 8033
TIME...MOT...LOC 2213Z 200DEG 24KT 3517 8058

$$

RWH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
453 PM EDT TUE APR 26 2011

.SYNOPSIS...
MOIST SOUTHERLY FLOW WILL CONTINUE ACROSS THE REGION THROUGH
TOMORROW EVENING. A COLD FRONT WILL THEN APPROACH FROM THE WEST
TOMORROW NIGHT AND MOVE EAST OF THE AREA ON THURSDAY. DRY HIGH
PRESSURE WILL DEVELOP IN THE WAKE OF THE FRONT AND REMAIN THROUGH
SATURDAY...WITH ANOTHER COLD FRONT APPROACHING FROM THE NORTHWEST
TOWARD THE BEGINNING OF NEXT WEEK.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
FOR THE LATE AFTERNOON UPDATE...POPS WILL NEED TO BE DECREASED QUITE
A BIT OVER THE MTNS FOR THE REMAINDER OF THE AFTERNOON INTO THE
EARLY EVENING. FAIRLY DENSE CIRRUS SHIELD HAS HINDERED HEATING OVER
THE HIGHER TERRAIN. IN ADDITION...DEWPOINTS HAVE ACTUALLY MIXED OUT
TO THE LOWER/MID 50S IN MANY AREAS. AS A RESULT...CAPE VALUES ARE
VERY TAME. WE WILL STILL FEATURE A CHANCE POP ALONG THE SOUTHERN
ESCARPMENT...BUT POPS WILL BE LOWERED TO SLIGHT CHANCE ACROSS THE
REMAINDER OF THE HIGH TERRAIN THROUGH 00Z. OVER THE PIEDMONT...
REMNANT SEA BREEZE BOUNDARY HAS PUSHED WELL INLAND...WITH SOME
ASSOCIATED ROBUST...ALBEIT WIDELY SCATTERED CONVECTION APPROACHING
EASTERN PORTIONS OF THE CWFA FROM THE EAST. SEVERE CELL OVER
LANCASTER COUNTY HAS SHOWN LITTLE SIGN OF WEAKENING...AND IS
BASICALLY RIDING UP THE INSTABILITY AXIS. THIS WILL PROBABLY ENTER
UNION COUNTY NC AROUND 530 PM EDT...AND SEE NO REASON WHY IT WON/T
BE SEVERE AT THAT POINT.

OTHERWISE...CONVERGENCE ALONG THE BOUNDARY IS ACTUALLY WEAKENING...
AS THE SURFACE FLOW TO ITS WEST IS QUITE BACKED. THEREFORE...WE
WON/T GO TOO CRAZY WITH PIEDMONT POPS...BUT WILL INCREASE THEM TO
40-50 OVER THE NEXT 3 HOURS.

TONIGHT...CONDITIONS APPEAR SUITABLE FOR THE DEVELOPMENT OF A WARM
CONVEYOR BELT OF UPSLOPE SHRA AND TSRA ACROSS THE ESCARPMENT. NAM
INDICATES THAT FLOW BETWEEN ATLANTIC HIGH PRESSURE AND LOW PRESSURE
OVER THE SOUTHERN MISSISSIPPI RIVER VALLEY WILL ADVECT VERY MOIST
AIR ACROSS THE SOUTHERN APPALACHIANS. NAM FORECAST SOUNDINGS SHOW PW
VALUES INCREASING OVER 1.5 INCHES... AROUND 200 PERCENT OF NORMAL.
IN ADDITION...CAPE VALUES WILL REMAIN OVER 500 J/KG AND MID TO U30S
K-INDEX ACROSS THE MTNS THROUGH THE OVERNIGHT HOURS. LFC LEVELS
ACROSS THE MTNS ARE FORECAST TO REMAIN LESS THAN 2 KFT. UPSLOPE FLOW
SHOULD AVERAGE IN THE MID 30S...ALLOWING EASY FORMATION OF SHRA AND
TSRA. GIVEN THE WIND FIELDS...WIDESPREAD INSTABILITY...HIGH MOISTURE
CONTENT...IT APPEARS THAT LINES OF CONVECTIVE CELLS WILL DEVELOP AND
CONTINUE ACROSS THE MTNS FOR MOST OF THE EVENING AND OVERNIGHT
PERIOD. AREAS UNDER THESE BANDS COULD QUICKLY SEE RAINFALL AMOUNTS
RANGE FROM 2 TO 4 INCHES. WE HAVE HIGHLIGHTED THE POTENTIAL FOR
EXCESSIVE RAIN WITH A FLASH FLOOD WATCH. LOWS WILL REMAIN WELL ABOVE
NORMAL...60S ACROSS THE MTNS TO MID 60S EAST.

WEDNESDAY...UNSTABLE UPSLOPE FLOW WILL CONTINUE ACROSS THE MTNS
THROUGH THE DAY...SUPPORTING SHRA. MOST OF THE MORNING HOURS WILL
SEE A WIDESPREAD LOW OVERCAST ACROSS THE CWA. AS THE CASE
RECENTLY...THE STRATUS WILL LIFT AND MIX TO CU BY MID DAY. WARM LLVL
THICKNESSES AND PERIODS OF INSOLATION SHOULD ALLOW TEMPS TO PEAK IN
THE MID 70S WEST TO L80S EAST. THE PRESSURE GRADIENT AHEAD OF AN
APPROACHING COLD FRONT WILL INCREASE THROUGH THE DAY. DEEPENING
MIXING AND GRADIENT SHOULD YIELD GUSTY SOUTHWEST WINDS DURING THE
AFTERNOON. BY THE LATE AFTERNOON...CAPES SHOULD RANGE BETWEEN 1000
TO 2000 J/KG. LATE AFTERNOON SHRA AND TSRA COVERAGE SHOULD RANGE
FROM LIKELY OVER THE MTNS TO SCT EAST. STRONG LLVL WIND PROFILES AND
MARGINAL INSTABILITY MAY SUPPORT A FEW SVR TSRA DURING THE AFTERNOON.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 230 PM TUESDAY...LINE OF CONVECTION AHEAD OF THE FRONT WILL BE
BEARING DOWN ON THE FCST AREA WED EVE AS THE UPPER TROF APPROACHES.
CAPE VALUES ARE EXPECTED TO DROP OFF WED EVE BUT WITH A 60KT LL SLY
JET AND SIGNIFICANT SHEAR...STRONG TSTMS ARE STILL EXPECTED WITH A
SEVERE STORM THREAT CONTINUING OVERNIGHT. THE FRONT MOVES THRU THE
AREA QUICKLY THU WITH MOST PRECIP CLEARING THE E CWA BY EARLY AFTN.
ANOTHER H5 SHORTWAVE MOVES IN THU NIGHT INTO FRI AND THERE WILL BE
SOME LOW CLOUDINESS OVER THE MTNS...BUT WITH DRY HIGH PRES BUILDING
IN FROM THE W AT THE SFC FCST REMAINS DRY. WITH LOWER THKNS VALUES
AND COOLER AIR MOVG IN HIGHS WILL BE COOLER THU-FRI BUT STILL
SLIGHTLY ABOVE AVG.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 2 PM TUESDAY...THE MEDIUM RANGE FCST BEGINS AT 00Z ON SATURDAY
WITH A STRONG H5 RIDGE BUILDING OVER THE AREA AND A BROAD UPPER TROF
DIGGING DOWN OVER THE WESTERN CONUS. THE RIDGE WILL GRADUALLY MOVE
OFFSHORE EARLY NEXT WEEK ON DAYS 6 AND 7 AS THE UPPER TROF
APPROACHES THE CWFA. THE LATEST GFS REMAINS A BIT MORE PROGRESSIVE
WITH THE UPPER LVL PATTERN AND MOVES THE UPPER TROF TO OUR DOORSTEP
ABOUT 12 HRS SOONER THAN THE SLOWER ECMWF. AT THE SFC...A DOME OF
HIGH PRESSURE WILL BE CENTERED OVER THE SE AND WILL SLOWLY BE PUSHED
OFF THE CAROLINA COAST OVER THE WEEKEND AS A WEAK COLD FRONT
APPROACHES THE FCST AREA. WINDS ARE EXPECTED TO GO FROM NEAR CALM ON
SAT TO SOUTHERLY ON SUN AND EARLY MON AND THEN VEER AROUND TO THE NW
AS THE FRONT PUSHES THRU. AS EXPECTED THE GFS IS ABOUT 12 TO 18 HRS
FASTER WITH THE FROPA. AFTER THE FROPA...MODELS HAVE ANOTHER SFC
HIGH MOVING IN ON DAY 7. I KEPT POPS BELOW 15% ON SAT INTO EARLY SUN
AND RAMP THEM UP SUN AFTERNOON/EVENING AS THE FLOW BECOMES SOUTHERLY
AND MORE MOIST. POPS THEN STEADILY INCREASE THRU THE DAY ON MONDAY
AND INTO TUES WITH THE APPROACH OF THE COLD FRONT. TEMPERATURES WILL
REBOUND TO ONE TO TWO CATEGORIES ABOVE NORMAL ON SAT AND
SUNDAY...WITH NEAR NORMAL TEMPS ANTICIPATED AFTER THE FROPA ON TUES.

&&

.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
AT KCLT...SOUTH-SOUTHWEST WILL CONTINUE ACROSS THE CLT TERMINAL
THROUGH THE TAF PERIOD. BUILDING INSTABILITY WILL SUPPORT AFTERNOON
AND EVENING SHRA AND TSRA...I WILL CARRY VCSH AND CB IN THE TAF.
AFTER SUNSET...DEEP MOISTURE WILL ADVANCE EAST TO WEST ACROSS THE
REGION. LATE TONIGHT...MVFR STRATUS WILL EXPAND ACROSS THE
REGION...LOWERING TO IFR AROUND SUNRISE WEDNESDAY. SIMILAR TO THE
PAST COUPLE OF MORNINGS...LOW CEILINGS WILL GRADUALLY RISE THROUGH
THE MORNING HOURS...IMPROVING TO MVFR BY LATE MORNING.

ELSEWHERE ACRS THE FA...SOUTH-SOUTHWEST WILL CONTINUE ACROSS THE
TERMINALS THROUGH THE TAF PERIOD. BUILDING INSTABILITY WILL SUPPORT
AFTERNOON AND EVENING SHRA AND TSRA...I WILL CARRY VCSH AND CB IN
THE TAFS. AFTER SUNSET...DEEP MOISTURE WILL ADVANCE EAST TO WEST
ACROSS THE REGION. STRONG UPSLOPE FLOW AND RICH LLVL MOISTURE WILL
RESULT IN EXPANDING UPSLOPE SHRA AND TSRA THIS EVENING AND
OVERNIGHT. LATE TONIGHT...MVFR STRATUS WILL EXPAND ACROSS THE
REGION...LOWERING TO IFR AROUND SUNRISE WEDNESDAY. SIMILAR TO THE
PAST COUPLE OF MORNINGS...LOW CEILINGS WILL GRADUALLY RISE THROUGH
THE MORNING HOURS...IMPROVING TO MVFR BY LATE MORNING.

OUTLOOK...UNSETTLED WX CONDS CONTINUE WEDNESDAY INTO WEDNESDAY NIGHT
AND PERHAPS THURSDAY MORNING AS NUMEROUS TO WIDESPREAD SHOWERS AND
EMBEDDED TSTMS ARE EXPECTED OUT AHEAD OF AN APPROACHING COLD FRONT.
DRYING CONDS WILL OVERSPREAD THE REGION LATER THURSDAY WITH FAIR WX
FRIDAY AND SATURDAY.

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR GAZ010.
NC...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR NCZ033-049-050-
     053-059-062>065-501>510.
SC...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR SCZ001>003.

&&

SYNOPSIS...JPT
NEAR TERM...JDL/NED
SHORT TERM...RB
LONG TERM...JPT
AVIATION...NED

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
325 PM EDT TUE APR 26 2011

GAZ017-018-026-028-029-NCZ035>037-048-051-052-056>058-068>072-082-
SCZ004>014-019-271930-
HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-ALEXANDER-IREDELL-DAVIE-
MADISON-SWAIN-HAYWOOD-CATAWBA-ROWAN-GRAHAM-CLEVELAND-LINCOLN-GASTON-
MECKLENBURG-CABARRUS-UNION NC-GREATER OCONEE-GREATER PICKENS-
GREATER GREENVILLE-SPARTANBURG-CHEROKEE-YORK-ANDERSON-ABBEVILLE-
LAURENS-UNION SC-CHESTER-GREENWOOD-
325 PM EDT TUE APR 26 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST GEORGIA...PIEDMONT
NORTH CAROLINA...WESTERN NORTH CAROLINA AND UPSTATE SOUTH CAROLINA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

THUNDERSTORMS ARE EXPECTED OVER THE WESTERN CAROLINAS AND
NORTHEAST GEORGIA THROUGH THIS EVENING. SOME OF THE THUNDERSTORMS
COULD BE SEVERE...WITH DAMAGING WIND GUSTS THE PRIMARY THREAT. A
FEW THUNDERSTORMS COULD ALSO PRODUCE HAIL AS LARGE AS QUARTERS.
HEAVY RAIN WILL BE POSSIBLE WITH ANY THUNDERSTORM AS WELL.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

A LINE OF STRONG TO SEVERE THUNDERSTORMS IS EXPECTED TO CROSS THE
REGION FROM THE WEST WEDNESDAY NIGHT AHEAD OF A COLD FRONT.
DAMAGING WINDS IN EXCESS OF 60 MPH WILL BE THE MAIN THREAT WITH
THESE THUNDERSTORMS...BUT LARGE HAIL WILL ALSO BE POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF LARGE
HAIL...DAMAGING WINDS...TORNADOES OR FLASH FLOODING TO OUR OFFICE.

GAZ010-NCZ033-049-050-053-059-062>065-501>510-SCZ001>003-271930-
RABUN-AVERY-YANCEY-MITCHELL-BUNCOMBE-NORTHERN JACKSON-MACON-
SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-CALDWELL MOUNTAINS-
GREATER CALDWELL-BURKE MOUNTAINS-GREATER BURKE-MCDOWELL MOUNTAINS-
EASTERN MCDOWELL-RUTHERFORD MOUNTAINS-GREATER RUTHERFORD-
POLK MOUNTAINS-EASTERN POLK-OCONEE MOUNTAINS-PICKENS MOUNTAINS-
GREENVILLE MOUNTAINS-
325 PM EDT TUE APR 26 2011

...FLASH FLOOD WATCH IN EFFECT THROUGH WEDNESDAY MORNING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST GEORGIA...WESTERN
NORTH CAROLINA AND UPSTATE SOUTH CAROLINA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   FLASH FLOOD WATCH.

THUNDERSTORMS ARE EXPECTED OVER THE WESTERN CAROLINAS AND
NORTHEAST GEORGIA THROUGH THIS EVENING. SOME OF THE THUNDERSTORMS
COULD BE SEVERE...WITH DAMAGING WIND GUSTS THE PRIMARY THREAT. A
FEW THUNDERSTORMS COULD ALSO PRODUCE HAIL AS LARGE AS QUARTERS.
HEAVY RAIN WILL BE POSSIBLE WITH ANY THUNDERSTORM AS WELL (SEE
FLASH FLOOD WATCH).

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   FLASH FLOOD WATCH.

A LINE OF STRONG TO SEVERE THUNDERSTORMS IS EXPECTED TO CROSS THE
REGION FROM THE WEST WEDNESDAY NIGHT AHEAD OF A COLD FRONT.
DAMAGING WINDS IN EXCESS OF 60 MPH WILL BE THE MAIN THREAT WITH
THESE THUNDERSTORMS...BUT LARGE HAIL WILL ALSO BE POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF LARGE
HAIL...DAMAGING WINDS...TORNADOES OR FLASH FLOODING TO OUR OFFICE.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
539 PM EDT TUE APR 26 2011

NCZ071-082-262230-
MECKLENBURG-UNION-
539 PM EDT TUE APR 26 2011

...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN MECKLENBURG AND
WESTERN UNION COUNTIES THROUGH 630 PM EDT...

AT 535 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR MINERAL SPRINGS...OR 10 MILES SOUTHWEST OF
MONROE...MOVING NORTH AT 25 MPH.

THIS STORM WILL BE NEAR...
  MONROE...
  STALLINGS...
  UNIONVILLE...
  MINT HILL...

DIME SIZE HAIL...AND WIND GUSTS UP TO 40 MPH ARE EXPECTED WITH THIS
STORM.

INTENSE LIGHTNING IS OCCURRING WITH THIS STORM. IF OUTDOORS...STAY
AWAY FROM ISOLATED HIGH OBJECTS SUCH AS TREES. MOVE INDOORS IF
POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS AND AVOID
USING TELEPHONES UNLESS IT IS AN EMERGENCY. TRY TO UNPLUG UNNECESSARY
ELECTRICAL APPLIANCES BEFORE THE THUNDERSTORM APPROACHES.

LAT...LON 3483 8061 3488 8080 3494 8079 3495 8080
      3534 8069 3527 8066 3519 8052 3519 8049
      3517 8045

RWH