Special Weather Statement, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
244 PM EDT SAT AUG 6 2011

.SYNOPSIS...
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE SOUTH ON
SUNDAY...THOUGH ANOTHER WEAK FRONT MAY STALL OVER THE MOUNTAINS LATE
SUNDAY AND REMAIN THERE TO START THE WEEK.  THE FRONT GETS PUSHED
SOUTH OF OUR AREA IN MID WEEK AS HIGH PRESSURE FROM THE NORTH BRINGS
SOME DRIER WEATHER.

&&

.NEAR TERM /THROUGH SUNDAY/...
AS OF 145 PM...CONVECTION HAS FINALLY INITIATED ACRS THE NC MTNS
WITHIN LAST COUPLE OF HOURS. LAPS ANALYSIS SHOWS PLENTY OF SBCAPE
VERY MOIST BL. DEEP WLY FLOW (15-20 KTS) IS ENUF TO PUSH THE STORMS
SLOWLY EAST FROM THE MTNS INTO THE PIEDMONT THIS AFTN AND EVENING.
LIKELY POPS STILL LOOKS GOOD. THE NAM BUFKIT MBE VELOCITIES ARE VERY
SLOW ACRS THE PIEDMONT. SO POTENTIAL FOR TRAINING STORMS EXISTS. AND
GIVEN PWATS STILL OVER 2.00 INCHES...A SMALL HEAVY RAIN THREAT STILL
EXISTS TODAY. SEVERE THREAT IS STILL LOW...BUT WITH FREEZING LEVELS
DOWN TO 14.5 TO 15 KFT WITH SOME FLOW...IT IS A LITTLE HIGHER THAT
LAST FEW DAYS.

REST OF TONIGHT...QUASI-ZONAL FLOW ACRS THE NORTHERN TIER OF THE
CONUS CONTINUES. GUIDANCE IN AGREEMENT ON A 700 MB JETLET TRACKING
ACRS THE OHIO VALLEY OVERNIGHT. VERY GOOD MOISTURE FLUX AND
LINGERING INSTBY MAY SUSTAIN CONVECTION UPSTREAM THRU THE NIGHT.
CONVECTION HAS BEEN ONGOING ALL DAY ACRS CENTRAL KY/TN...AND THE
DEBRIS MOISTURE FROM THAT CLUSTER WILL WORK INTO THE CWFA. SO MOSTLY
CLOUDY SKIES EXPECTED WITH DWINDLING CONVECTION EXPECTED. SOME
UPSTREAM PRECIP MAY MOVE INTO THE NC MTNS BEFORE DAYBREAK. LOWS WILL
CONTINUE TO BE MILD UNDER CLOUDS AND HUMIDITY (UPR 60S MTNS AND
LWR-MID 70S PIEDMONT).

SUNDAY...OVERALL W/NWLY FLOW CONTINUES TO STRENGTHEN AS TROFINESS
AMPLIFIES SLIGHTLY OVER THE NORTHEAST STATES. A WEAKENING MCV IS
PROGGED TO TRACK THRU THE CWFA DURING THE AFTN. SLIGHTLY BETTER
DOWNSLOPE EAST OF THE MTNS MAY MIX DWPTS INTO THE MID 60S...BUT
STILL EXPECT AT LEAST SCATTERED CONVECTION TO DEVELOP (POSSIBLY
NUMEROUS SHWRS/TSTMS IN THE MTNS). HYDRO CONCERNS SHUD BE LOWER WITH
THE INCREASED FLOW...BUT SEVERE THREAT WILL CONTINUE (MAINLY ISOLD
WET MICROBURSTS). TEMPS BACK INTO THE UPR 80S MTN VLYS AND MID-UPR
90S PIEDMONT...BUT MIXED DWPTS SHUD KEEP HEAT INDEX BELOW 105.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
AS OF 100 PM SAT...THE UPPER LEVEL JET STREAM SHOULD STRETCH
FROM THE OH VALLEY TO SRN NEW ENGLAND SUN NIGHT THROUGH TUE AS A
BROAD BUT SHALLOW TROUGH DEVELOPS OVER THE E. THIS WILL ALLOW
RIPPLES OF UPPER DIVERGENCE AND OCCASIONAL SHORTWAVES TO CROSS THE
FORECAST AREA...ESPECIALLY THE NRN TIER...THROUGH THE PERIOD. THE
PROFILES DO SHOW SOME MID AND UPPER DRYING IN THE WNW FLOW ON SUN
NIGHT AND MON. HOWEVER...UPSTREAM MCS DEVELOPMENT OVER THE MIDWEST
IS VERY LIKELY AND THE SRN APPALACHIANS WILL SIT SQUARELY DOWNSTREAM
OF ANY ACTIVITY IN THE WNW FLOW ALOFT. WILL THUS NEED SOLID WRN MTN
CHC POPS THROUGH THE PERIOD. A SFC TROUGH WILL REMAIN ACROSS THE
PIEDMONT MON THROUGH TUE...BUT PRECIP CHANCES WILL BE MORE DIURNAL
IN NATURE THERE...AND GENERALLY IN THE LOWER CHANCE RANGE. IN THE
IMPROVING WESTERLY FLOW ALOFT...20 TO 30 KT OF 6 KM BULK SHEAR COULD
BE REALIZED AT TIMES. SOME ORGANIZATION OF DISCRETE CONVECTIVE CELLS
COULD BE POSSIBLE ACROSS FOOTHILL AND PIEDMONT AREAS EACH AFTERNOON
IF THIS SHEAR MATERIALIZES. HEAT INDEX VALUES COULD APPROACH 105
ALONG THE SE FRINGE MON AFTN...BUT TEMPS SHOULD BE A CATEGORY COOLER
ON TUE IF A WEAK FRONTAL ZONE LAYS OVER INTO THE AREA FROM THE NW AS
EXPECTED.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 230 PM SATURDAY...THE GFS AND ECMWF CONTINUE TO BE IN FAIRLY
GOOD AGREEMENT WITH THE UPPER LEVEL TROFINESS OVER THE EASTERN PART
OF THE NATION.  FOR THE SECOND HALF OF THE UPCOMING WEEK.  THE
SURFACE FRONT WILL PUSH SOUTH OF THE AREA TUESDAY NIGHT WITH A
SECONDARY FRONT COMING DOWN FROM THE NORTH ON WEDNESDAY BUT LITTLE
IF ANY MOISTURE WILL BE PRESENT.  GENERALLY DRY WEATHER IS EXPECTED
INTO NEXT WEEKEND. THE GFS HOLDS OFF THE MOISTURE UNTIL FRIDAY THEN
BRINGS IN MINOR VORTS FROM THE WEST ALONG WITH ITS EASTERN GULF LOW.
THE ECMWF KEEPS ALL DRY OVER OUR REGION UNTIL LATE SATURDAY BUT
MOISTURE IS NOT AS ROBUST AS IN THE GFS.  MOISTURE WILL CONTINUE TO
INCREASE AHEAD THE NEXT APPROACHING COLD FRONT WHICH WILL ARRIVE
FROM THE NORTHWEST NEXT SUNDAY.  TEMPERATURES WILL BE ABOVE NORMAL
BY ONE TO TWO CATEGORIES THROUGH THE PERIOD.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
AT KCLT...CIGS SHUD LIFT TO VFR BY 18Z...WITH VFR CONDITIONS
EXPECTED INTO THE EVENING. THE EXCEPTION WILL BE SHRA AND
TSRA...WHICH ARE STILL EXPECTED TO BECOME NUMEROUS ACRS THE AREA
LATE AFTN AND EVENING. THEY ARE NOT ORGANIZED SUCH THAT NO TEMPO CAN
BE MADE YET. BUT THE MAIN WINDOW OF GREATEST COVERAGE IS EXPECTED TO
BE 20Z TO 02Z. OVERNIGHT...THERE WILL BE PLENTY OF MID-UPR LEVEL
CLOUDINESS WHICH SHUD LIMIT FOG DEVELOPMENT. BUT CONSENSUS AMONGST
GUIDANCE IS FOR MVFR HZ TO DEVELOP BY DAYBREAK SUNDAY. WINDS WILL BE
LIGHT OR CALM AND FAVOR A SWLY DIRECTION THRU THE PERIOD.

ELSEWHERE...ALL SITES EXPECTED TO BE VFR BY 18Z...WITH MAIN CONCERN
GOING FORWARD BEING CONVECTION. DEEP CONVECTION THIS AFTERNOON
EXPECTED TO BECOME NUMEROUS BEFORE DISSIPATING THIS EVENING. AT TIME
OF ISSUANCE...STORMS FILLING IN JUST WEST OF KAVL. SO CONFIDENCE
HIGH ENUF FOR DIRECT IMPACT TO ADD TEMPO IFR IN TSRA. STORMS WILL
ROLL OFF THE MTNS TO AFFECT THE UPSTATE SITES AND KHKY IN THE 19 TO
02Z TIME FRAME. MID LEVEL CLOUDINESS WILL LINGER THRU THE OVERNIGHT
AND LIMIT LATE NIGHT VSBY RESTRICTIONS (FOR NOW JUST HAVE MVFR AT
KAVL).

OUTLOOK...MOISTURE WILL GRADUALLY DIMINISH INTO EARLY NEXT WEEK AS
LOW LEVEL FLOW TURNS TOWARD THE WEST. HOWEVER...CHANCES FOR ISOLATED
TO WIDELY SCATTERED AFTERNOON/EVENING SHOWERS/TS WILL REMAIN THROUGH
THE PERIOD.

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...DEO
NEAR TERM...ARK
SHORT TERM...HG
LONG TERM...DEO
AVIATION...ARK

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
417 AM EDT SAT AUG 6 2011

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-070830-
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-
417 AM EDT SAT AUG 6 2011

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

.DAY ONE...TODAY AND TONIGHT.

SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP OVER THE REGION TODAY. STORMS SHOULD MOVE A LITTLE MORE
QUICKLY TODAY THAN THEY DID ON FRIDAY. HOWEVER...THE AIRMASS OVER
THE WESTERN CAROLINAS AND NORTHEAST GEORGIA REMAINS EXTREMELY
MOIST AND SOME THUNDERSTORMS WILL PRODUCE LOCALLY EXCESSIVE
RAINFALL. A FEW STORMS MAY ALSO PRODUCE SMALL AREAS OF DAMAGING
WINDS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

A WEAK FRONT WILL STALL OVER THE MOUNTAINS ON SUNDAY. THE FRONT WILL
PROVIDE A FOCUS FOR SCATTERED THUNDERSTORMS SUNDAY AND MONDAY.
SOME OF THE THUNDERSTORMS MAY BECOME SEVERE AND PRODUCE DAMAGING
WINDS.

.SPOTTER INFORMATION STATEMENT...

NONE.

14

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
106 PM EDT SAT AUG 6 2011

NCZ064-065-061745-
HENDERSON-TRANSYLVANIA-
106 PM EDT SAT AUG 6 2011

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN TRANSYLVANIA AND
WESTERN HENDERSON COUNTIES THROUGH 145 PM EDT...

AT 105 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES NORTHWEST OF BREVARD...MOVING EAST AT 15
MPH.

THIS STORM WILL BE NEAR...
  BREVARD...
  ETOWAH...

PEA SIZE HAIL AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM. THE THUNDERSTORM WILL PRODUCE VERY HEAVY RAINFALL AS WELL.

LAT...LON 3516 8250 3515 8254 3516 8254 3516 8256
      3518 8289 3530 8289 3532 8287 3532 8284
      3532 8283 3537 8279 3540 8250

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
211 PM EDT SAT AUG 6 2011

NCZ053-065-061845-
BUNCOMBE-HENDERSON-
211 PM EDT SAT AUG 6 2011

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN HENDERSON AND
SOUTHWESTERN BUNCOMBE COUNTIES THROUGH 245 PM EDT...

AT 211 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES SOUTHWEST OF CANDLER...OR 12 MILES
SOUTHWEST OF DOWNTOWN ASHEVILLE...MOVING EAST AT 15 MPH.

THIS STORM WILL BE NEAR...
  I-26 AT I-40...
  AVERY CREEK...
  BILTMORE FOREST...

PEA SIZE HAIL AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM. HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS.

LAT...LON 3559 8242 3537 8245 3542 8274 3544 8278
      3547 8280 3553 8278 3554 8276 3556 8278
      3557 8277 3560 8280 3561 8280

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
305 PM EDT SAT AUG 6 2011

NCZ065-508>510-061930-
EASTERN POLK-GREATER RUTHERFORD-HENDERSON-POLK MOUNTAINS-
305 PM EDT SAT AUG 6 2011

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL RUTHERFORD...EASTERN
HENDERSON AND POLK COUNTIES THROUGH 330 PM EDT...

AT 302 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR LAKE ADGER...OR 6 MILES NORTH OF COLUMBUS...
MOVING EAST AT 5 MPH.

THIS STORM WILL BE NEAR...
  LAKE ADGER...
  LAKE ADGER...

PEA SIZE HAIL...AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM. A PERIOD OF HEAVY RAIN CAN ALSO BE EXPECTED.

LAT...LON 3546 8199 3521 8198 3524 8233 3542 8234
      3543 8228 3540 8226 3540 8224 3540 8219
      3544 8215

RB

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
331 PM EDT SAT AUG 6 2011

SCZ006-007-062000-
GREATER GREENVILLE-SPARTANBURG-
331 PM EDT SAT AUG 6 2011

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL GREENVILLE AND WESTERN
SPARTANBURG COUNTIES THROUGH 400 PM EDT...

AT 327 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR HAYWOOD MALL...OR 5 MILES EAST OF DOWNTOWN
GREENVILLE...MOVING EAST AT 5 MPH.

THIS STORM WILL BE NEAR...
  SHOPS AT GREENRIDGE...
  SHOPS AT GREENRIDGE...
  PELHAM ROAD AT I-85...
  FIVE FORKS...

PEA SIZE HAIL...AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM. A PERIOD OF HEAVY RAIN CAN ALSO BE EXPECTED.

LAT...LON 3475 8242 3493 8242 3496 8212 3475 8211
      3475 8212 3478 8215 3474 8217

RB

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
343 PM EDT SAT AUG 6 2011

NCZ506-508-062015-
EASTERN MCDOWELL-GREATER RUTHERFORD-
343 PM EDT SAT AUG 6 2011

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN RUTHERFORD AND
SOUTHEASTERN MCDOWELL COUNTIES THROUGH 415 PM EDT...

AT 340 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES SOUTHWEST OF THERMAL CITY...OR 7 MILES
NORTHWEST OF RUTHERFORDTON...MOVING EAST AT 20 MPH.

THIS STORM WILL BE NEAR...
  THERMAL CITY...
  SPINDALE...
  BOSTIC...

PEA SIZE HAIL...AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM. A PERIOD OF HEAVY RAIN CAN ALSO BE EXPECTED.

LAT...LON 3535 8170 3534 8171 3535 8208 3538 8211
      3550 8211 3557 8205 3559 8183 3558 8182
      3558 8180 3559 8180 3559 8178 3561 8173

RB

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
406 PM EDT SAT AUG 6 2011

NCZ070-071-SCZ009-062030-
GASTON-MECKLENBURG-YORK-
406 PM EDT SAT AUG 6 2011

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN YORK...SOUTHERN GASTON
AND SOUTHWESTERN MECKLENBURG COUNTIES THROUGH 430 PM EDT...

AT 405 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR CROWDERS...OR 6 MILES SOUTH OF GASTONIA...
MOVING EAST AT 10 MPH.

THIS STORM WILL BE NEAR...
  GASTONIA...
  CRAMERTON...

PEA SIZE HAIL...AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM. A PERIOD OF HEAVY RAIN CAN ALSO BE EXPECTED.

LAT...LON 3527 8098 3505 8100 3509 8133 3527 8131

RB