Severe Thunderstorm Warning 642, NWS Greenville-Spartanburg, SC

464 
WWUS52 KGSP 211947
SVSGSP

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
347 PM EDT SUN AUG 21 2011

GAC105-119-147-212015-
/O.CON.KGSP.SV.W.0642.000000T0000Z-110821T2015Z/
ELBERT GA-FRANKLIN GA-HART GA-
347 PM EDT SUN AUG 21 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR HART...EASTERN FRANKLIN AND NORTHWESTERN ELBERT COUNTIES...

AT 342 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR CARNESVILLE...MOVING EAST AT 10 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
FRANKLIN SPRINGS...VANNA...ROYSTON...REED CREEK...NUBERG...LAVONIA...
HARTWELL...DEWY ROSE...CANON...BOWMAN AND BOWERSVILLE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PEOPLE IN THE PATH OF THIS STORM SHOULD BE ALERT FOR LARGE HAIL AND
DAMAGING WINDS. FREQUENT LIGHTNING AND LOCALLY HEAVY RAIN CAN OCCUR
WITH ANY THUNDERSTORM. SEEK SHELTER INDOORS AWAY FROM WINDOWS AND
DOORS UNTIL THE STORM PASSES.

&&

LAT...LON 3406 8295 3410 8304 3414 8306 3417 8311
      3423 8308 3426 8313 3423 8318 3426 8330
      3447 8326 3448 8288 3445 8286
TIME...MOT...LOC 1947Z 281DEG 10KT 3433 8323

$$

07

351 
WWUS52 KGSP 212010
SVSGSP

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
410 PM EDT SUN AUG 21 2011

GAC105-119-147-212020-
/O.EXP.KGSP.SV.W.0642.000000T0000Z-110821T2015Z/
ELBERT GA-FRANKLIN GA-HART GA-
410 PM EDT SUN AUG 21 2011

...THE SEVERE THUNDERSTORM WARNING FOR HART...EASTERN FRANKLIN AND
NORTHWESTERN ELBERT COUNTIES WILL EXPIRE AT 415 PM EDT...

THE THUNDERSTORM WEAKENED BELOW SEVERE LIMITS.

LAT...LON 3406 8295 3410 8304 3414 8306 3417 8311
      3423 8308 3426 8313 3423 8318 3426 8330
      3447 8326 3448 8288 3445 8286
TIME...MOT...LOC 2010Z 281DEG 10KT 3432 8315

$$

07

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
243 PM EDT SUN AUG 21 2011

.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION TONIGHT...AND SETTLE JUST
SOUTHEAST OF THE AREA ON MONDAY. DRIER AIR WILL ARRIVE AS HIGH
PRESSURE BUILDS TO THE NORTHWEST ON TUESDAY. ATLANTIC MOISTURE WILL
THEN STEADILY RETURN TO THE REGION DURING THE LATER PART OF THE
WEEK. THE PROGRESS OF TROPICAL SYSTEM IRENE WILL NEED TO BE CLOSELY
MONITORED FOR NEXT WEEKEND.

&&

.NEAR TERM /THROUGH MONDAY/...
LATEST WV IMAGES INDICATES A SIGNIFICANT CONVECTIVE DERIVED MID
LEVEL VORT OVER EXTREME WESTERN NC. THIS FEATURE WILL PUSH ACROSS
THE FOOTHILLS AND PIEDMONT DURING THE REST OF THE AFTERNOON...MOVING
EAST BY EARLY EVENING. VIS SATE SHOWS WIDESPREAD MID AND HIGH CLOUDS
ALONG AND AHEAD OF THE FEATURE. AT 18Z...CU REMAINS LARGELY LIMITED
TO NE GA AND JUST EAST OF THE CLT METRO AREA. DEWPOINTS ACROSS THE
REGION ARE EXPECTED TO RANGE IN THE U60S TO AROUND 70...PRODUCING
CAPES BETWEEN 2500 TO 3500 J/KG. IT APPEARS THAT SHRA/TSRA WILL
GRADUALLY DEVELOP AND INCREASE IN COVERAGE BETWEEN 20Z TO 0Z. AIR MASS
AND STORM MODE INFORMATION BELOW.

I WILL FORECAST LIKELY POPS ACROSS THE HIGH ELEVATIONS ALONG THE
EASTERN SLOPES AND ALONG THE I-85 CORRIDOR FROM KGMU EAST TO CLT
LATE THIS AFTERNOON AND EARLY EVENING. ELSEWHERE...I WILL FORECAST
SOLID CHC POPS THROUGH 2Z.

OBSERVED SOUNDINGS AT KFFC AND KGSO MODIFIED TO AFTERNOON TEMP/DEWPT
INDICATES CAPES WILL LIKELY REACH BETWEEN 2500-3500 J/KG. FZL ON
BOTH SOUNDINGS ARE SLIGHTLY ABOVE 15 KFT WITH WBZ BETWEEN 12 TO 13
KFT. SATELLITE BLENDED TOTAL PW AND SOUNDINGS INDICATE VALUES
BETWEEN 1.5 TO 1.8 INCHES. IN ADDITION...FORECAST SOUNDINGS INDICATE
INCREASING MID LEVEL FLOW AROUND 20 TO 30 KTS WITH SWEAT VALUES
BETWEEN 200-300. WIND PROFILES FAVOR THE DEVELOPMENT OF MULTICELL
STORMS...LIKELY SW TO NE ORIENTED LINES OF STORMS...STORM MOTIONS
EAST. GIVEN THE STORM STRUCTURE...WIND FIELDS...DCAPE AROUND 1000
J/KG...AND MODERATE INSTABILITY...IT APPEARS THAT SEVERAL DAMAGING
WIND EVENTS WILL OCCUR THROUGH EARLY EVENING. HIGH FREEZING LEVELS
MAY LIMIT LARGE HAIL EVENT TO ONLY A FEW. IN ADDITION...PW ABOVE 125
PERCENT AND RECENT HEAVY RAINFALL MAY RESULT IN PATCHES OF EXCESSIVE
RUNOFF.

TONIGHT...DEEP CONVECTION SHOULD MOVE EAST OF THE CWA BY MID
EVENING. MODELS TIME A WEAK COLD FRONT TO MOVE NW TO SE ACROSS THE
CWA LATE TONIGHT AND EARLY MONDAY MORNING. PARTIAL CLEARING BEHIND
THE FRONT SHOULD OCCUR FROM WEST TO EAST. NNW WINDS WILL
LIKELY DEVELOP AND PERSIST...LIMITING THE OVERALL FOG POTENTIAL. LOW
TEMPERATURES SHOULD RANGE AROUND NORMAL. EXPECT PATCHES OF LOW
UPSLOPE CLOUDS AND ISO SHRA/TSRA TO REMAIN ACROSS THE WESTERN SLOPES
THROUGH DAYBREAK.

MONDAY...THE COLD FRONT WILL COMPLETLEY MOVE SOUTH OF THE
CWA...RESULTING IN A STEADY FALL IN DEWPOINTS. HOWEVER...DAYTIME
HEATING AND CONVERGENCE ALONG THE FRONT MAY SUPPORT A FEW SHRA/TSRA
ACROSS THE UPPER SAVANNAH RIVER VALLEY AND SOUTHERN UPSTATE...I WILL
FORECAST 20 POPS. OTHERWISE...TEMPS WILL WARM QUICKLY WITH MOSTLY TO
PARTLY SUNNY CONDITIONS. HIGHS MAY VERIFY 2 TO 4 DEGREES ABOVE
TODAY/S VALUES.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 130 PM SUNDAY...THE SHORT TERM FCST PICKS UP AT 00Z ON TUESDAY
WITH THE AXIS OF THE UPPER TROF LOCATED TO OUR NORTHEAST AND A STEEP
UPPER RIDGE COVERING THE WESTERN TWO THIRDS OF THE CONUS. HEIGHTS
ARE EXPECTED TO RISE THRU THE PERIOD AS THE UPPER TROF LIFTS TO THE
NE AND THE UPPER RIDGE MAINTAINS ITS STRENGTH TO OUR WEST. ON
WED..MODELS GENERATE A FAIRLY POTENT LOOKING H5 SHORTWAVE OVER THE
GREAT LAKES AND PROPAGATE IT TOWARDS THE FCST AREA WED
AFTERNOON/EVENING. ITS LOOKING LIKE THE SW MIGHT PASS TO FAR TO THE
NORTH TO PROVIDE MUCH IN THE WAY OF DYNAMIC LIFTING OVER THE CWFA
BUT OF COURSE IT COULD TRACK FARTHER TO THE SOUTH.

ON TUESDAY...A SFC HIGH WILL RIDGE DOWN FROM THE NW BRINGING COOLER
AND DRIER NORTHERLY LOW LVL FLOW WITH MOSTLY CLEAR SKIES AND TEMPS
RIGHT AROUND CLIMO. ON WEDNESDAY...THE SFC HIGH GETS PUSHED OFF THE
EASTERN SEABOARD AND OUR BOUNDARY LAYER FLOW VEERS AROUND TO THE NE
AND THEN EAST. THIS SHOULD PROVIDE SOME INCREASED LOW TO MID LVL
MOISTURE...HOWEVER AT THIS POINT MOST OF THE MODEL GUIDANCE IS
SUGGESTING THAT ANY MOISTURE SURGE WILL BE MODEST THRU 00Z THURS.
THERE WILL LIKELY BE A BROAD AREA OF UPPER LVL DIVERGENCE OVER THE
FCST AREA WED AFTERNOON/EVENING...HOWEVER MOST OF THE LIFT COULD BE
GENERATED TO OUR NORTH. I DO RAMP POPS UP FROM THE LATE MORNING
HOURS THRU THE EVENING WITH AT LEAST A SLIGHT CHANCE OVER MOST OF
THE CWFA AT SOME POINT...YET I DOUBT WE WILL SEE ANY WIDESPREAD
CONVECTION. TEMPS ARE EXPECTED TO BE A DEGREE OR TWO COOLER THAN THE
PREVIOUS DAY...WITH THE LOWER ELEVATIONS REACHING THE UPPER 80S AND
THE LOWER 80S IN THE MT VALLEYS.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 215 PM SUNDAY...THE MEDIUM RANGE PART OF THE FORECAST WILL
CONTINUE TO FOCUS UPON THE FATE OF IRENE NEXT WEEKEND. BEFORE THE
STORM MAKES ITS APPROACH FROM THE SOUTH...WE WILL HAVE TO DEAL WITH
SOME MINOR CONCERNS LATE IN THE WEEK...MADE MORE COMPLICATED BY THE
PRESENCE OF IRENE. THE TREND IN THE GUIDANCE IS TO SHEAR APART A
SHORT WAVE DROPPING DOWN FROM THE NORTHWEST ON WEDNESDAY NIGHT AS A
COL REGION DEVELOPS OVER THE CAROLINAS WITH IRENE MOVING NORTH OF
CUBA. THIS WILL LIKELY HALT THE PROGRESS OF A SURFACE FRONT AND
CAUSE IT TO STALL ON THE W SIDE OF THE MTNS ON THURSDAY. IF THAT
HAPPENS...WE WILL LOSE SOME OF THE IMPETUS FOR SHOWER AND
THUNDERSTORM ACTIVITY FOR THURSDAY AND FRIDAY. IN FACT...THE MODELS
RETAIN SOME WEAK HIGH PRESSURE ACROSS THE WESTERN CAROLINAS IN
BETWEEN THE FRONT W OF THE MTNS AND IRENE TO THE S. THIS WOULD ALSO
BE MORE UNFAVORABLE FOR CONVECTION. BOTTOM LINE IS THINGS ARE
LOOKING SOMEWHAT DRIER FOR THURSDAY AND FRIDAY AND PRECIP CHANCES
WILL BE DIMINISHED...WHILE TEMPS ARE NUDGED UP A BIT.

FOR SATURDAY AND SUNDAY...THE LATEST GUIDANCE CONTINUES TO MOVE A
LOW OF TROPICAL ORIGIN SOMEWHERE ACROSS THE CAROLINAS...BUT THERE IS
A GREAT DEAL OF UNCERTAINTY REGARDING THE TRACK. SOMETHING FARTHER
WEST LIKE THE 00Z ECMWF WOULD RESULT IN A SIGNIFICANT AMOUNT OF RAIN
AND A HIGH POTENTIAL FOR FLOODING...WHILE A TRACK SIMILAR TO THE 12Z
GFS MIGHT ONLY AFFECT THE WRN PIEDMONT. THE FORECAST WILL CONTAIN A
40-50 PERCENT CHANCE OF RAIN WHICH IS MORE OF A MEASURE OF THE
UNCERTAINTY IN THE LOW TRACK. OBVIOUSLY IF THE LOW TAKES A WESTERN
TRACK WE ARE LOOKING AT CERTAIN HEAVY RAIN...BUT EVEN THE EASTERN
TRACK WOULD REQUIRE A CATEGORICAL POP AROUND CHARLOTTE. THE BEST
ADVICE FOR NOW IS FOR ALL INTERESTS ACROSS THE WESTERN CAROLINAS AND
NORTHEAST GEORGIA TO MONITOR THE FORECAST FOR NEXT WEEKEND.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...WIDESPREAD HIGH CLOUDS WILL GRADUALLY MOVE
EAST LATER THIS AFTERNOON. EXPECTED CU TO INCREASE ACROSS THE REGION
THROUGH 19Z...FOLLOWED BY SHRA/TSRA AN HOUR OR TWO LATER. IT APPEARS
THAT GREATEST PERIOD FOR TSRA WILL OCCUR BETWEEN 22Z AND 02Z. I WILL
INCLUDE A CB MENTION AT ALL TAF SITES...WITH TEMPOS FOR ALL SITES
EXCEPT HKY AND AVL. A WEAK COLD FRONT IS EXPECTED TO SWEEP NW TO SE
ACROSS THE REGION TONIGHT AND EARLY MONDAY MORNING. AFTER
FROPA...WINDS WILL FAVOR A DIRECTION BETWEEN 340 TO 010 DEGREES
AROUND 8 KTS. DWPTS WILL LIKELY FALL OVERNIGHT THROUGH MONDAY. FOG
WILL REMAIN LIMITED TO AREAS OF RAINFALL OR WITHIN THE VALLEYS.

OUTLOOK...DRIER CONDITIONS ARE EXPECTED BEHIND A COLD FRONT ON
MONDAY AND TUESDAY. MORE UNSETTLED WEATHER IS EXPECTED TO RETURN BY
MID WEEK AS ANOTHER COLD FRONT STALLS OVER THE AREA. MORNING FOG
WILL BE POSSIBLE...ESP IN MTN VALLEYS AND WHERE RAIN FALLS THE DAY
BEFORE.

AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...

WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

&&

SYNOPSIS...JPT
NEAR TERM...NED
SHORT TERM...JPT
LONG TERM...PM
AVIATION...NED

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
453 AM EDT SUN AUG 21 2011

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-220900-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-AVERY-ALEXANDER-
IREDELL-DAVIE-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-CATAWBA-
ROWAN-GRAHAM-NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA-
HENDERSON-CLEVELAND-LINCOLN-GASTON-MECKLENBURG-CABARRUS-UNION NC-
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-GREATER OCONEE-
GREATER PICKENS-GREATER GREENVILLE-SPARTANBURG-CHEROKEE-YORK-
ANDERSON-ABBEVILLE-LAURENS-UNION SC-CHESTER-GREENWOOD-
453 AM EDT SUN AUG 21 2011

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

.DAY ONE...TODAY AND TONIGHT.

SHOWERS AND THUNDERSTORMS WILL DEVELOP IN AND NEAR THE MOUNTAINS
THIS AFTERNOON...AND THEN MOVE EASTWARD THROUGH THE PIEDMONT
DURING THE LATE AFTERNOON AND EVENING HOURS. SOME OF THESE
THUNDERSTORMS MAY BECOME SEVERE...PRODUCING DAMAGING WIND GUSTS
AND HAIL AS LARGE AS QUARTERS. THE THUNDERSTORMS WILL ALSO PRODUCE
FREQUENT LIGHTNING AND TORRENTIAL RAINFALL. ANY LOCATIONS AFFECTED
BY MULTIPLE THUNDERSTORMS COULD SEE LOCALIZED FLOODING.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

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

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
231 PM EDT SUN AUG 21 2011

NCZ065-509-510-SCZ003-007-211915-
EASTERN POLK-GREENVILLE MOUNTAINS-HENDERSON-POLK
MOUNTAINS-SPARTANBURG-
231 PM EDT SUN AUG 21 2011

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN GREENVILLE...
NORTHWESTERN SPARTANBURG...SOUTHERN HENDERSON AND SOUTHERN POLK
COUNTIES THROUGH 315 PM EDT...

AT 227 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR TUXEDO...OR 7 MILES SOUTH OF
HENDERSONVILLE...MOVING EAST AT 20 MPH.

THIS STORM WILL BE NEAR...
  NORTH SALUDA RESERVOIR...
  TRYON...
  LANDRUM...

SMALL HAIL...AND WIND GUSTS OF 40 TO 50 MPH ARE EXPECTED WITH THIS
STORM.

LAT...LON 3525 8200 3501 8207 3505 8222 3506 8222
      3506 8224 3515 8257 3532 8251

07

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
248 PM EDT SUN AUG 21 2011

GAZ018-026-028-211930-
FRANKLIN-HART-STEPHENS-
248 PM EDT SUN AUG 21 2011

...A STRONG THUNDERSTORM WILL AFFECT FRANKLIN...SOUTHEASTERN STEPHENS
AND WESTERN HART COUNTIES THROUGH 330 PM EDT...

AT 243 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES WEST OF CARNESVILLE...MOVING EAST AT 10
MPH.

THIS STORM WILL BE NEAR...
  MARTIN...
  CARNESVILLE...
  CANON...

SMALL HAIL...AND WIND GUSTS OF 40 TO 50 MPH ARE EXPECTED WITH THIS
STORM.

LAT...LON 3426 8313 3423 8317 3424 8325 3430 8338
      3432 8340 3443 8339 3452 8335 3446 8294
      3423 8306 3422 8308

07

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
305 PM EDT SUN AUG 21 2011

SCZ014-211945-
CHESTER-
305 PM EDT SUN AUG 21 2011

...A STRONG THUNDERSTORM WILL AFFECT EASTERN CHESTER COUNTY THROUGH
345 PM EDT...

AT 300 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES NORTHEAST OF CHESTER...MOVING EAST AT 10
MPH.

THIS STORM WILL BE NEAR...
  RICHBURG...

SMALL HAIL...AND WIND GUSTS OF 40 TO 50 MPH ARE EXPECTED WITH THIS
STORM.

LAT...LON 3468 8087 3465 8089 3457 8088 3465 8127
      3482 8124 3482 8089 3479 8087 3477 8086
      3474 8087 3469 8085

07