Special Weather Statement, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1236 PM EDT SAT JUL 23 2011

.SYNOPSIS...
AN UPPER LEVEL RIDGE WILL CONTINUE TO DOMINATE THE WEATHER THROUGH
MONDAY. A TROUGH OF LOW PRESSURE WILL DEVELOP ALONG THE EAST COAST
THE FIRST PART OF THE WEEK... BUT WILL BE QUICKLY REPLACED WITH A
RIDGE OF HIGH PRESSURE ONCE AGAIN LATE IN THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
SYNOPTIC FEATURES AFFECTING OUR WEATHER TODAY ARE ONLY NOMINALLY
DIFFERENT THAN THE PAST FEW DAYS...FEATURING STRONG RIDGING ALOFT
AND SFC LEE TROUGHING. OBSERVED LLVL THICKNESS VALUES AND 85H TEMPS
WOULD INDICATE MAX TEMPS IN THE MID TO UPPER 90S ACRS THE
FTHLS/PIEDMONT. AGAIN...WITH THE 12 UTC NAM KEYING ON A DOWNWARD
MIXING OF BLYR DWPTS THIS AFTERNOON BANKING ON A LOWERING OF SFC
DWPTS REGIONWIDE...KEEPING MAX APPARENT TEMPS OF 105 DEG F LIMITED
TO THE GOING HEAT ADVISORY AREA.

THE RUC/S DEPICTION OF WEAK VORT AIDING IN CENTRAL APPALACHIAN TSTM
DEVELOPMENT ATTM IS PROGGED TO SINK ESE TODAY. WHILE EXPECTING
TERRAIN TO AID IN THE MOST TSTM CVRG THIS AFTERNOON...THERE IS
SUPPORT FROM THE 12 UTC NAM...RUC HRRR AND WRF-ARW THAT TSTM
ACTIVITY WILL BE OF GREATER CVRG INTO THE NC PIEDMONT THAN
YSTDY...PERHAPS THE RESULT OF SLIGHTLY BETTER LIFT FROM
AFOREMENTIONED VORT. WOULD EXPECT TSTM MODE TO BE OF THE PULSE
VARIETY AGAIN TODAY...FEATURING ISOLATED GUSTY WIND AND ISOLATED
HEAVY RAIN.

DEEP CONVECTION SHOULD DISSIPATE SOON AFTER THE LOSS OF HEATING AND
ANOTHER WARM AND MUGGY NIGHT IS ON TAP.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AT 2 AM EDT SATURDAY...AN UPPER TROUGH WILL DEVELOP ALONG THE EAST
COAST SUNDAY AND MONDAY...LOWERING HEIGHTS ACROSS OUT AREA...WHILE A
STRONG RIDGE REMAINS TO OUR WEST. A WARM AND MOIST AIR MASS WILL
REMAIN OVER OUR AREA...WITH LEE TROUGHING EAST OF THE MOUNTAINS. A
COLD FRONT MOVES SOUTHEAST OUT OF THE OH RIVER VALLEY MONDAY...REACH
NC BY MONDAY NIGHT. SCATTERED CONVECTION IS EXPECTED SUNDAY
AFTERNOON AND EVENING AS CAPE APPROACHES 1000 J/KG. CONVECTIVE
CHANCES WILL BE GREATER ON MONDAY AS THE TROUGH AMPLIFIES AND THE
COLD FRONT APPROACHES. TEMPERATURES WILL BE QUITE WARM ON SUNDAY...
THEN START TO DROP BY MONDAY AS HEIGHTS FALL...BUT WILL STILL BE A
CATEGORY OR TWO ABOVE NORMAL.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 1220 PM SATURDAY...THE 0600 UTC RUN OF THE GFS WAS A LITTLE
DEEPER THAN THE 00 UTC ECMWF WITH THE TROF OVER NEW ENGLAND AND THE
MID ATLANTIC STATES TUE-WED. AS A RESULT THE GFS PUSHES A TROUGH
WELL SOUTH OF THE REGION BY TUE NIGHT. IT/S REALLY NOT MUCH OF A
FRONT IN THAT THE UPSTREAM AIRMASS IS JUST AS HOT AS THE AIRMASS
AHEAD IT...JUST DRIER AS IT ORIGINATES OVER THE MID-CONTINENT. SOUTH
OF THE BNDRY THE AIRMASS IS MUCH MORE MOIST. IN FACT...THE GFS SPINS
UP SEVERAL VORTICITY CENTERS ALONG THE BNDRY WHICH APPEAR TO TAKE ON
TROPICAL CHARACTERISTICS. PER THE GFS...ALL OF THESE FEATURES WILL
BE SOUTH OF THE FA WITH THE RIDGE HOLDING SWAY OVER THE FA. IN
FACT...THE GFS ENSEMBLE STRENGTHENS THE RIDGE MORE BY NEXT FRI AND
SAT THAN DOES THE OPERATIONAL RUN...AN INDICATION THAT WE WILL HAVE
ANOTHER ROUND OVER VERY HOT CONDITIONS LATE IN THE EXTENDED.

THE OPERATIONAL EC IS SIMILAR OVERALL...THOUGH IT DOESN/T PUSH THE
BNDRY AS FAR SOUTH. THIS IDEA IS ALSO SUPPORTED BY THE GFS ENSEMBLE.
IT DEVELOPS IT/S OWN VORTICITY CENTER ON THE TAIL END OF THE FRONT
WHICH IS ACCOMPANIED BY PLENTY OF PCPN. WHILE FARTHER NORTH...THIS
FEATURE APPEARS THAT IT WILL STAY WELL WEST OF THE FA. LATE IN THE
PERIOD IT ALSO STRENGTHENS THE RIDGE IMPLYING A RETURN OF THE VERY
HOT CONDITIONS. AND EVEN WHILE WED/THU MAY NOT BE QUITE AS
HOT...BOTH DAYS WILL STILL HAVE ABOVE NORMAL TEMPERATURES...SO WE
REALLY WON/T GET MUCH OF A BREAK. ONLY ISLD TSTMS ARE EXPECTED WED
AND THU...WITH A LITTLE BETTER COVERAGE FRI AND SAT OVER THE MTNS.
THERE IS A SMALL CHANCE OF MUCH BETTER COVERAGE ONE OR TWO DAYS
DURING THE EXTENDED IF ONE OF THOSE MCV/S ALONG THE FRONT FORMS OVER
OUR FA...BUT THE CHANCES OF THIS LOOK RATHER SLIM AND IT SHOULD BE
MAINLY DRY.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AT KCLT...THERE WILL REMAIN THE SMALL POSSIBILITY OF A TSTM
AFFECTING THE TERMINAL FROM MID-AFTERNOON TO EARLY EVENING...ENUF
OF A CHANCE TO CONTINUE TO MENTION CB. SW WINDS ABT 8 KTS TO BECOME
LIGHT THIS EVENING AS LINGERING CONVECTIVE AND HIGH CLOUDS DIMINISH.
UNLESS IT RAINS THIS AFTERNOON...DO NOT EXPECT ANY PRE-DAWN VSBY
ISSUES.

ELSEWHERE ACRS THE FA...TSTMS ARE EXPECTED TO BE SCATTERED MAINLY
ACRS WESTERN NC INTO EARLY EVENING WITH ISOLATED ACTIVITY ELSEWHERE.
OVERNIGHT...UNLESS IT RAINS AT ONE OF THE UPSTATE SC TERMINALS OR
KHKY...ANY VSBY ISSUES DURING THE PRE-DAWN HOURS WILL NOT BE WORSE
THAN BRIEF MVFR. IT RAINED JUST BRIEFLY AT KAVL FRIDAY AFTERNOON AND
STILL THE RESULT WAS AN EXTENSIVE PERIOD OF IFR...THERE IS MORE THAN
JUST TOKEN SUPPORT FOR A PERIOD OF IFR FROM THE LATEST GUIDANCE AND
WILL PLAN ON FCSTG AS SUCH.

OUTLOOK...DOMINANT MID LEVEL RIDGE WILL REMAIN OVER THE REGION THIS
WEEKEND. ISOLD TO SCATTERED TSRA ARE POSSIBLE EACH AFTERNOON AND
EVENING...MAINLY OVER THE HIGH TERRAIN. AREAS OF RAIN COULD BE
FOLLOWED BY PATCHES OF EARLY MORNING FOG. THE RIDGE WILL BREAK DOWN
A BIT EARLY NEXT WEEK AND THE BEST CONVECTIVE COVERAGE IS EXPECTED
MONDAY EVENING AS A FRONTAL BOUNDARY MOVES INTO THE REGION.

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...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR GAZ029.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ037-057-
     070>072-082.
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ009-011>014-
     019.

&&

SYNOPSIS...JAT
NEAR TERM...BSH/CSH
SHORT TERM...JAT
LONG TERM...JAT
AVIATION...BSH/CSH

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
533 AM EDT SAT JUL 23 2011

GAZ010-017-018-026-028-NCZ033-035-036-048>053-056-058-059-062>065-
068-069-501>510-SCZ001>008-010-241000-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-AVERY-ALEXANDER-IREDELL-
MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-CATAWBA-GRAHAM-
NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-
CLEVELAND-LINCOLN-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-ANDERSON-
533 AM EDT SAT JUL 23 2011

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

.DAY ONE...TODAY AND TONIGHT.

THUNDERSTORMS ARE IN THE FORECAST FOR TODAY AND TONIGHT. THE MAIN
HAZARD FROM THESE THUNDERSTORMS WILL BE CLOUD TO GROUND LIGHTNING.

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

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

GAZ029-NCZ037-057-070>072-082-SCZ009-011>014-019-241000-
ELBERT-DAVIE-ROWAN-GASTON-MECKLENBURG-CABARRUS-UNION NC-YORK-
ABBEVILLE-LAURENS-UNION SC-CHESTER-GREENWOOD-
533 AM EDT SAT JUL 23 2011

...HEAT ADVISORY IN EFFECT FROM NOON TODAY TO 8 PM EDT THIS
EVENING...

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

.DAY ONE...TODAY AND TONIGHT.

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

   HEAT ADVISORY.

THUNDERSTORMS ARE IN THE FORECAST FOR TODAY AND TONIGHT. THE MAIN
HAZARD FROM THESE THUNDERSTORMS WILL BE CLOUD TO GROUND LIGHTNING.

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

HEAT AND HUMIDITY ARE EXPECTED TO PRODUCE HEAT INDEX VALUES OF 105
OT 107 DEGREES SUNDAY AFTERNOON IN THE PIEDMONT.

.SPOTTER INFORMATION STATEMENT...

NONE.

07

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1208 PM EDT SAT JUL 23 2011

NCZ505-231645-
MCDOWELL MOUNTAINS-
1208 PM EDT SAT JUL 23 2011

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL MCDOWELL COUNTY THROUGH
1245 PM EDT...

AT 1159 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR BUSICK...OR 10 MILES NORTHWEST OF MARION...
MOVING EAST AT 15 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO WOODLAWN.

PEA SIZE HAIL...AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM.

FREQUENT 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 3584 8205 3580 8203 3572 8203 3574 8219
      3576 8216 3580 8216 3585 8209

MCAVOY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1249 PM EDT SAT JUL 23 2011

NCZ503>506-231715-
BURKE MOUNTAINS-EASTERN MCDOWELL-GREATER BURKE-MCDOWELL MOUNTAINS-
1249 PM EDT SAT JUL 23 2011

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL MCDOWELL AND WESTERN
BURKE COUNTIES THROUGH 115 PM EDT...

AT 1243 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES EAST OF WOODLAWN...OR 8 MILES NORTH OF
MARION...MOVING SOUTHEAST AT 5 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO LAKE
  JAMES...WOODLAWN...TABLE ROCK AND NEBO.

WIND GUSTS UP TO 40 MPH ARE EXPECTED WITH THIS STORM.

FREQUENT 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 3585 8176 3570 8181 3573 8209 3586 8200

MCAVOY