Severe Thunderstorm Warning 641, NWS Greenville-Spartanburg, SC

789 
WWUS52 KGSP 211850
SVSGSP

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

NCC089-211900-
/O.CAN.KGSP.SV.W.0641.000000T0000Z-110821T1930Z/
HENDERSON NC-
250 PM EDT SUN AUG 21 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL HENDERSON COUNTY
IS CANCELLED...

THE SEVERE THUNDERSTORM MOVED SOUTHEAST AND OUT OF HENDERSON COUNTY.

LAT...LON 3524 8203 3499 8214 3513 8247 3520 8241
      3521 8239 3518 8237 3519 8236 3523 8235
      3524 8236 3525 8235 3528 8235 3530 8233
TIME...MOT...LOC 1850Z 290DEG 9KT 3519 8231

$$

NCC149-SCC045-083-211930-
/O.CON.KGSP.SV.W.0641.000000T0000Z-110821T1930Z/
SPARTANBURG SC-POLK NC-GREENVILLE SC-
250 PM EDT SUN AUG 21 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM EDT
FOR NORTHEASTERN GREENVILLE...SOUTHERN POLK AND NORTHWESTERN
SPARTANBURG COUNTIES...

AT 244 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 3 MILES SOUTH OF SALUDA...OR 8 MILES SOUTHWEST OF COLUMBUS...
MOVING EAST AT 10 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
TRYON...GOWENSVILLE...LANDRUM AND CAMPOBELLO

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 3524 8203 3499 8214 3513 8247 3520 8241
      3521 8239 3518 8237 3519 8236 3523 8235
      3524 8236 3525 8235 3528 8235 3530 8233
TIME...MOT...LOC 1850Z 290DEG 9KT 3519 8231

$$

07

378 
WWUS52 KGSP 211901
SVSGSP

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

NCC149-SCC045-083-211911-
/O.CAN.KGSP.SV.W.0641.000000T0000Z-110821T1930Z/
SPARTANBURG SC-POLK NC-GREENVILLE SC-
301 PM EDT SUN AUG 21 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN GREENVILLE...
SOUTHERN POLK AND NORTHWESTERN SPARTANBURG COUNTIES IS CANCELLED...

THE THUNDERSTORM WEAKENED BELOW SEVERE LIMITS.

LAT...LON 3524 8203 3499 8214 3513 8247 3520 8241
      3521 8239 3518 8237 3519 8236 3523 8235
      3524 8236 3525 8235 3528 8235 3530 8233
TIME...MOT...LOC 1901Z 290DEG 9KT 3518 8228

$$

07

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

.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY...CROSS THE
REGION TONIGHT...AND SETTLE JUST SOUTHEAST OF THE AREA ON MONDAY.
DRIER AIR WILL ARRIVE AS HIGH PRESSURE BUILDS OVER TO THE NORTH ON
TUESDAY. ATLANTIC MOISTURE WILL STEADILY RETURN TO THE REGION
WEDNESDAY THROUGH FRIDAY. THE PROGRESS OF TROPICAL SYSTEM IRENE WILL
NEED TO BE CLOSELY MONITORED FOR NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
LATEST WV IMAGES INDICATES A SIGNIFICANT CONVECTIVE DERIVED MID
LEVEL VORT OVER MIDDLE TN/KY. THIS FEATURE WILL PUSH ACROSS THE MTNS
AROUND MID DAY AND EAST ACROSS THE FOOTHILLS AND PIEDMONT DURING THE
AFTERNOON. VIS SATE SHOWS WIDESPREAD CLOUDS ALONG AND AHEAD OF THE
FEATURE...WITH CLOUD COVER BEGINNING TO INCREASE ACROSS THE MTNS AND
CIRRUS EAST OF THE MTNS AT 1545Z. DEWPOINTS ACROSS THE REGION ARE
EXPECTED TO RANGE IN THE U60S TO AROUND 70...PRODUCING CAPES BETWEEN
2000 TO 3000 J/KG. IT APPEARS THAT SHRA/TSRA WILL DEVELOP DURING THE
EARLY AFTERNOON AND INCREASE EAST DURING THE LATE AFTERNOON AND
EARLY EVENING. AIR MASS AND STORM MODE INFORMATION BELOW.

BASED ON SATE TREND..I WILL UPDATE THE FORECAST TO INCREASE CLOUD
COVER THROUGH TODAY. POP FORECAST WILL BE CRAFTED TO INDICATE SCT TO
NUM COVERAGE EARLY THIS AFTERNOON...THEN PUSHING EAST THIS AFTERNOON
AND EVENING AS COVERAGE DECREASES WEST. THE GOING HIGH TEMP FORECAST
APPEARS ON TRACK.

OBSERVED SOUNDINGS AT KFFC AND KGSO MODIFIED TO THIS AFTERNOON
TEMP/DEWPT INDICATES CAPES WILL LIKELY REACH BETWEEN 2500-3000 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...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. THE
CURRENT HWO LOOKS GOOD.

TONIGHT...CONVECTION SHOULD MOVE EAST OF THE CWA BY THE EARLY
MORNING HOURS. PARTIAL CLEARING SHOULD OCCUR FROM WEST TO EAST
ACROSS THE REGION. NNW WINDS WILL LIKELY DEVELOP AND
PERSIST...LIMITING THE OVERALL FOG POTENTIAL. LOW TEMPERATURES
SHOULD RANGE AROUND NORMAL.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
AS OF 215 AM SUNDAY...A PROMINENT E COAST TROUGH WILL BE IN PLACE
MON...WITH DEEP LAYER NW FLOW INTO THE REGION. ALTHOUGH THE SFC COLD
FRONT SHOULD SETTLE SE OF THE AREA THROUGH THE DAY...THE FORECAST
MODELS ARE GENERATING SOME ISOLD MTN CONVECTION IN LINGERING POST
FRONTAL BOUNDARY LAYER MOISTURE. WILL CAP ANY MTN POPS AROUND 20
PERCENT MON. TEMPS SHOULD WARM INTO THE LOWER 90S MOST AREAS OUTSIDE
OF THE MTNS IN THE NW DOWNSLOPE FLOW.

HEIGHTS WILL RECOVER SOMEWHAT INTO TUE AND DRY SFC HIGH PRESSURE
WILL BUILD OVER FROM THE N. TEMPS WILL BE NEAR NORMAL TO JUST BELOW
NORMAL IN THE COOLER THICKNESSES AND NRLY FLOW...AND DEWPOINTS
SHOULD FALL DOWN WELL INTO THE 50S.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 215 AM SUNDAY...A SHORTWAVE TROUGH WILL SHARPEN UP OVER THE
MIDWEST TUE NIGHT. MEANWHILE...LOW LEVEL FLOW WILL TURN SE ACROSS
THE FORECAST AREA THROUGH WED...ALLOWING ATLANTIC MOISTURE TO
GRADUALLY RETURN TO THE REGION. THE HANDLING OF THE ARRIVAL OF THIS
UPSTREAM TROUGH WILL PLAY A ROLE NOT ONLY IN INCREASING CONVECTIVE
COVERAGE WED THROUGH THU...BUT ALSO WITH THE EVENTUAL STEERING OF
TROPICAL SYSTEM IRENE ACROSS THE SE U.S. LATER IN THE PERIOD. FOR
NOW...WILL FEATURE CHC MTN TO SLIGHT CHC PIEDMONT POPS ON WED...THEN
RAMP UP TO MORE SOLID CHC COVERAGE THROUGHOUT ON THU AS THE
SHORTWAVE PASSES.

THE IRENE CIRCULATION WILL ALSO LIKELY PUSH NWD TOWARD FL ON
THURSDAY. THERE IS SOME CONSENSUS DEVELOPING THAT THE BELT OF BETTER
WESTERLY FLOW MAY RETREAT NE INTO NEW ENGLAND THROUGH
FRIDAY...CREATING ENOUGH OF A WEAKNESS IN THE UPPER FLOW THAT THE
IRENE REMNANTS COULD THREATEN THE WESTERN CAROLINAS AND NORTHEAST
GEORGIA BY THE WEEKEND. IN ADDITION...A COLD FRONT WILL ARRRIVE FROM
THE NW ON FRI AND LIKELY STALL IN THE VICINITY THROUGH SAT. THIS
COULD BECOME A FOCUS FOR HEAVY CONVECTIVE RAIN SHOWERS IN ADVANCE OF
THE IRENE CIRCULATION. ALL INTERESTS WILL NEED TO PAY VERY CLOSE
ATTENTION TO THIS SYSTEM THROUGH THE WEEK.

&&

.AVIATION /18Z 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...HG
NEAR TERM...NED
SHORT TERM...HG
LONG TERM...HG
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