Special Weather Statement, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
756 PM EDT TUE AUG 21 2012

.SYNOPSIS...
WEAK LOW PRESSURE WILL TRACK SLOWLY EAST ALONG A FRONTAL BOUNDARY
THAT LAYS ACROSS THE CAROLINAS...REACHING THE COAST ON THURSDAY.
HIGH PRESSURE WILL THEN SETTLE IN ACROSS THE SOUTHEAST AND REMAIN
INTO NEXT WEEK.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
AS OF EARLY EVENING...ISOLATED SHOWER ACTIVITY CONTINUES ON THE
EASTERN FRINGE...MAINLY S OF CLT...BUT MORE ACTIVITY HAS DEVELOPED
OFF THE BLUE RIDGE ACROSS THE UPSTATE AND SRN FOOTHILLS OF NC. WILL
HAVE TO AMEND PRECIP CHANCES ONCE AGAIN TO ACCOUNT FOR THIS. EXPECT
THE BROKEN BAND E OF THE BLUE RIDGE TO CONTINUE TO PRECIPITATE UNTIL
AN HOUR OR SO AFTER SUNSET AND ANY REMAINING INSTABILITY IS USED UP.
MOST OF THIS WILL BE SHOWERS...BUT A FEW RUMBLES WILL NOT BE RULED
OUT IN THE TALLER CONVECTION. TEMPS ARE OKAY AWAY FROM LOCATIONS
THAT HAVE BEEN RAIN COOLED.

REMAINDER OF PREVIOUS DISCUSSION...

THE TROF AXIS PUSHES INTO THE MTNS OVERNIGHT AND LITTLE IN THE WAY
OF COUPLED FORCING IS NOTED ON THE CROSS SECTIONS. EXPECT THE LLVL
CLOUD COVER TO DIMINISH WITH THE LOSS OF HEATING AND CLEARING CONDS
ACROSS THE MTNS TO PRODUCE PERHAPS SOME DENSE FG BY DAYBREAK. LOWS
SHOULD BE A FEW DEGREES BELOW NORMAL.

ON WEDNESDAY...THE UPPER TROF BECOMES A BIT MORE DISORGANIZED AS IT
PUSHES INTO THE CWFA. BOTH THE GFS AND NAM INDICATE A SIGFNT
WEAKENING OF Q/VECT CONVERGENCE DURING THE DAY AND ONCE AGAIN NO
REAL CONNECTION TO ANY OR MINIMAL LLVL OMEGA. THERE WILL STILL BE
SOME MOISTURE AND ENOUGH MECH LIFT ACROSS THE MTNS FOR ISOL
-SHRA...AND PERHAPS A COUPLE TSTMS BY THE AFTERNOON. MOST AREAS
OUTSIDE THE MTNS SHOULD REMAIN DRY AS WELL...BUT CANNOT RULE OUT A
FEW SHOWERS ACROSS THE ERN ZONES WHERE UPPER ENERGY WAVES COULD
SUPPORT ISOL -SHRA IN A MOSTLY STABLE ENVIRONMENT. WITH NE/LY
MAINTAINED...HIGH TEMPS SHOULD REMAIN A CAT OR SO BELOW NORMAL.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 230 PM EDT TUESDAY...MODELS SHOW WEAK UPPER TROUGH MOVING
ACROSS THE CAROLINAS MID TO LATE WEEK. BETTER VORTICITY ADVECTION
LOOKS TO BE EAST OF THE CWA BY THE BEGINNING OF THE SHORT TERM
PERIOD. NOT MUCH SEEN IN TERMS OF MID/UPPER FEATURES DURING THE
PERIOD...LEAVING DIURNAL SHOWERS/STORMS AS THE MAIN CONCERN THU AND
FRI. BETTER INSTABILITY ON THURSDAY PER NAM SOUNDINGS...BUT WEAK
EASTERLY FLOW DOES SET UP BY FRIDAY WHICH HELPS MOISTEN THE COLUMN.
WIDESPREAD PRECIP THUS SEEMS MORE LIKELY ON FRIDAY.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 230 PM EDT TUESDAY...SURFACE RIDGE OVER EASTERN SEABOARD WILL
PERSIST THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK...THOUGH IT
APPEARS TO GRADUALLY WEAKEN. EASTERLY FLOW OVER THE CAROLINAS AND
RESULTING UPGLIDE COULD BRING SOME CLOUDS/PRECIP OVER THE
WEEKEND...MAINLY SATURDAY. DECENT WINDS SEEN ON 300K ISENTROPIC
SURFACE BUT CONDENSATION PRESSURE DEFICITS ARE FAIRLY HIGH. SOME
INDICATION OF A SURFACE BOUNDARY PUSHING THROUGH THE AREA TUESDAY
AND AN INCREASE IN MOISTURE BEHIND IT. THIS WARRANTS INCREASED POPS
FOR TUE/TUE NIGHT.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...NO FLIGHT RESTRICTIONS ARE EXPECTED OVER THE NEXT 24 HRS.
DEEPER CONVECTION SHOULD REMAIN W/NW AND S OF KCLT THROUGH MID
EVENING. THERE COULD BE A BRIEF PERIOD OF FOG OR LOW CLOUDS AROUND
DAYBREAK ON WEDNESDAY GIVEN A LIGHT EASTERLY FLOW OVERNIGHT BUT THE
CHANCES OF THIS HAPPENING APPEAR TOO LOW TO INCLUDE IN THE TAF RIGHT
NOW. INSTEAD...HAVE KEPT THE LOWER CLOUDS SCATTERED IN THE 040 TO
050 RANGE. AFTER SUNRISE...A LIGHT NE FLOW WILL PERSIST THROUGH THE
DAY WITH SCATTERED TO BROKEN VFR LOW CLOUDS. EXPECT A FEW MORE
SHOWERS AROUND IN THE AFTERNOON BUT THE CHANCE REMAINS TOO LOW TO
INCLUDE AT THIS TIME.

ELSEWHERE...AN AREA OF DEEP CONVECTION OVER METRO GREENVILLE WILL
KEEP MVFR/IFR VIS/CEILING RESTRICTIONS NEARBY THROUGH 02Z OR SO.
AFTERWARD...EXPECT SOME MVFR FOG DEVELOPMENT IN RAIN COOLED AIR. VIS
COULD BE VARIABLE AS FOG COMES AND GOES. THIS SHOULD DIMINISH A BIT
TOWARD DAYBREAK. THE OTHER TAF SITES WILL ALSO HAVE THE CHANCE OF A
FOG RESTRICTION IN THE MORNING. KAVL GETS A PREVAILING MVFR AS
CONFIDENCE IS HIGHER...WHEREAS KAND/KHKY ONLY GET A TEMPO. WINDS
WILL COME UP FROM THE NE AFTER DAYBREAK WITH GENERALLY VFR LOW CLOUD
CEILINGS DURING THE DAY.

OUTLOOK...ISOLATED AFTN TSTMS ARE EXPECTED THURSDAY AND FRIDAY...
MAINLY OVER THE MTNS. MORNING FOG IS LIKELY IN THE FRENCH BROAD
VALLEY AND A BRIEF PERIOD OF MORNING FOG IS POSSIBLE AT SOME OF THE
FOOTHILL AND PIEDMONT TAF SITES JUST ABOUT ANY DAY.

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...PAT
NEAR TERM...PM/SBK
SHORT TERM...JW
LONG TERM...JW
AVIATION...PM

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
340 PM EDT TUE AUG 21 2012

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-222000-
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-
340 PM EDT TUE AUG 21 2012

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SCATTERED THUNDERSTORMS WILL OCCUR THIS AFTERNOON...MAINLY EAST OF
THE MOUNTAINS. THESE STORMS MAY PRODUCE TORRENTIAL RAINFALL AND
OCCASIONAL LIGHTNING. URBAN AREAS AND OTHER POORLY DRAINED AREAS
SHOULD MONITOR FOR POSSIBLE FLASH FLOODING FOLLOWING HEAVY RAIN.

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

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

WIMBERLEY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
918 PM EDT TUE AUG 21 2012

NCZ035-036-056-220145-
ALEXANDER-CATAWBA-IREDELL-
918 PM EDT TUE AUG 21 2012

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN CATAWBA...SOUTHERN
ALEXANDER AND WESTERN IREDELL COUNTIES THROUGH 945 PM EDT...

AT 914 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES EAST OF ST. STEPHENS...OR 6 MILES EAST OF
HICKORY...MOVING NORTH AT 5 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  ST. STEPHENS...
  CONOVER...

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

LAT...LON 3579 8097 3562 8126 3569 8137 3583 8132
      3591 8101

CSH

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
941 PM EDT TUE AUG 21 2012

NCZ035-036-056-220215-
ALEXANDER-CATAWBA-IREDELL-
941 PM EDT TUE AUG 21 2012

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN CATAWBA...SOUTHEASTERN
ALEXANDER AND WESTERN IREDELL COUNTIES THROUGH 1015 PM EDT...

AT 938 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES SOUTHWEST OF LOOKOUT SHOALS LAKE...OR 8
MILES NORTHEAST OF NEWTON...MOVING NORTHEAST AT 20 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  LOOKOUT SHOALS LAKE...
  STONY POINT...

SMALL HAIL...WIND GUSTS UP TO 40 MPH AND TORRENTIAL RAIN ARE EXPECTED
WITH THIS STORM.

FREQUENT LIGHTNING IS OCCURRING WITH THIS STORM. IF OUTDOORS...TRY TO
GET INDOORS OR INTO A HARD TOPPED VEHICLE. OTHERWISE...STAY AWAY FROM
OPEN AREAS AND ISOLATED HIGH OBJECTS SUCH AS TREES. WHEN INDOORS...
STAY AWAY FROM WINDOWS AND DOORS AND AVOID USING WIRED ELECTRONIC
DEVICES. TRY TO UNPLUG UNNECESSARY APPLIANCES BEFORE THE STORM
APPROACHES.

LAT...LON 3582 8121 3591 8103 3583 8092 3572 8094
      3564 8119 3572 8131

CSH