Special Weather Statement, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1007 PM EDT THU JUL 19 2012

.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN AND MOVE SOUTH TODAY. THIS WILL ALLOW
A FRONTAL BOUNDARY OVER THE OHIO VALLEY TO DROP SOUTH...INTO THE
CAROLINAS EARLY SATURDAY. THE FRONT WILL REMAIN OVER OR JUST SOUTH
OF THE REGION THROUGH THE WEEKEND AND DISSIPATE ON MONDAY.

&&

.NEAR TERM /THROUGH FRIDAY/...
AS OF 10 PM...ALTHOUGH CONVECTION HAS BECOME MUCH LESS ORGANIZED
ALONG PUSHING SOUTH ACROSS WESTERN NC...MODERATE INSTABILITY AND A
VERY MOIST AIR MASS IS STILL SUPPORTING SCATTERED TO NUMEROUS
CONVECTIVE CELLS ALONG THE I-40 CORRIDOR LATE THIS EVENING. LIKELY
POPS HAVE THEREFORE BEEN EXPANDED FURTHER SOUTH AND EAST...ALMOST TO
THE I-85 CORRIDOR IN NC. THE BEST COLD POOL FORCING IS OCCURRING
ACROSS THE NC FOOTHILLS ATTM. AS THIS ACTIVITY CONTINUES TO EXPAND
TOWARD THE SOUTHERN FOOTHILLS AND SOUTHWEST PIEDMONT...IT WILL
ENCOUNTER AN AIR MASS THAT WAS OVERTURNED FAIRLY WELL BY LATE
AFTERNOON/EARLY EVENING CONVECTION...SO IM STILL NOT CONFIDENT
ENOUGH TO RAISE POPS ABOVE A TOKEN CHANCE ALONG THE I-85 CORRIDOR.
THE SEVERE WEATHER POTENTIAL REMAINS QUITE LOW WITH THIS ACTIVITY...
AS THE MORE ROBUST INSTABILITY IS WELL TO OUR WEST. NEVERTHELESS...
AN ISOLATED PULSE SEVERE STORMS CANNOT BE RULED OUT.

A COLD FRONT WILL APPROACH FROM THE NORTH ON FRIDAY...WHILE A PAIR
OF SHORTWAVES MOVES INTO THE BASE OF THE TROUGH. POPS AND QPF WILL
BE SIGNIFICANTLY HIGHER ON FRIDAY IN ADVANCE OF THE FRONT.
INSTABILITY WILL BE SUFFICIENT FOR SEVERE THUNDERSTORMS AGAIN...AND
WITH UNIDIRECTIONAL SHEAR PRESENT...SOME ORGANIZATION IS POSSIBLE...
ESPECIALLY IN THE PIEDMONT. WITH BETTER STEERING FLOW AND MOVING
STORMS...ANY HEAVY PRECIPITATION AMOUNTS WOULD BE FROM TRAINING OR
REPEATING CELLS. MAXIMUM TEMPERATURES WILL BE NEAR NORMAL...AS
ENOUGH BREAK IN CLOUD COVER WILL PERMIT HEATING TO OCCUR.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 235 PM THURSDAY...SHORT WAVE TROF WITH A SERIES OF ENERGY
MAXES REMAINS OVER THE AREA FRI NITE AND SAT. SFC COLD FRONT BECOMES
STALLED ACROSS THE AREA AS WELL. THE ENERGY MAXES AND RIGHT ENTRANCE
REGION OF THE UPPER JET WILL PROVIDE SOME SYNOPTIC SCALE FORCING AND
UPPER DIVERGENCE WHILE THE FRONT PROVIDES LOW LEVEL CONVERGENCE.
STILL EXPECT A DIURNAL TREND TO THE CONVECTION...BUT THE COPIOUS
MOISTURE AND LARGE SCALE FORCING SHUD KEEP AT LEAST SOME ACTIVITY
GOING MUCH OF THE NIGHT FRI NITE. NUMEROUS COVERAGE IS EXPECTED
AGAIN FOR SATURDAY FOR THE SAME REASONS...AS IS THE LINGERING
COVERAGE OVERNIGHT. HOWEVER...AREAS OUTSIDE OF THE WRN MOUNTAINS
COULD SEE BETTER COVERAGE. LOWS WILL BE NEAR NORMAL...BUT HIGHS WILL
BE BELOW NORMAL WITH MORE CLOUDS EARLIER PRECIP ONSET.

THE SHORT WAVE TROF MOVES EAST OF THE AREA SUNDAY...BUT A SHEAR AXIS
WILL REMAIN IN ITS PLACE. THE FRONT WILL BEGIN TO WASH OUT...BUT A
WEAK BOUNDARY WILL LIKELY LINGER. LOOKS LIKE COVERAGE COULD BE A
LITTLE LESS THAN SATURDAY WITH LESS UPPER SUPPORT...BUT SHUD BE AT
LEAST SCT. LOWS WILL BE A TAD COOLER...BUT HIGHS SHUD REBOUND TO
JUST BELOW NORMAL.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 215 PM THURSDAY...A WEAK TROF WILL KEEP A SPLIT OVER THE AREA
BETWEEN THE WEST-CENTRAL CONUS RIDGE AND THE BERMUDA RIDGE. AT THE
SFC...A LEE TROF AND COPIOUS LOW LEVEL MOISTURE WILL BE OVER THE
AREA. THIS WILL LEAD TO SCT DIURNAL TSRA AND NEAR TO SLIGHTLY ABOVE
NORMAL TEMPS. ON TUE AND WED...SHORT WAVES MOVING THRU THE NRN
STREAM FLOW HELP CARVE OUT AN UPPER TROF OVER THE EAST COAST. AT THE
SFC...LOW LEVEL MOISTURE AND THE LEE TROF REMAIN IN PLACE FOR TUE
WHILE A BACK DOOR COLD FRONT APPROACHES ON WED. AGAIN...GIVEN THE
MOISTURE...INSTABILITY AND WEAK FORCING...GENERALLY SCT DIURNAL
CONVECTION IS EXPECTED BOTH DAYS. TEMPS WILL INCREASE TO ABOVE
NORMAL BY WED. THE TROF MOVES OFF THE COAST THU AND RIDGING BEGINS
TO REASSERT ITSELF OVER THE SERN US AS MORE SHORT WAVE ENERGY MOVES
ACROSS THE NRN TIER OF THE COUNTRY. THE BACK DOOR FRONT MOVES NORTH
AWAY FROM THE AREA AS WELL. STILL EXPECT ENUF MOISTURE AND
INSTABILITY TO LINGER FOR SCT DIURNAL CONVECTION ONCE AGAIN. TEMPS
WILL FALL A DEGREE OR TWO FOR THU.

&&

.AVIATION /02Z FRIDAY THROUGH TUESDAY/...
AT KCLT AND ELSEWHERE...DIURNAL CONVECTION HAS MOVED AWAY FROM THE
TERMINALS THIS EVENING. HOWEVER...A MORE ORGANIZED AREA OF
CONVECTION WAS APPROACHING THE NORTHERN NC MTNS AND FHILLS FROM THE
NORTHWEST AT 755 PM. THIS ACTIVITY IS DECREASING IN INTENSITY FAIRLY
QUICKLY AS IT MOVES OVER THE RUGGED TERRAIN OF THE SOUTHERN
APPALACHIANS...AND IT IS NOT CERTAIN HOW FAR SOUTHEAST IT WILL PUSH
BEFORE DISSIPATING. OUR BEST GUESS IS TO INCLUDE A VCTS AT KHKY AND
KAVL BY 02Z. WE HAVE ALSO INCLUDED A TEMPO FOR -SHRA AT KHKY BETWEEN
04 AND 06Z...AS WE EXPECT TS CELLS ALONG THE LEADING EDGE OF THE
CONVECTIVE SYSTEM TO BE WIDELY SCATTERED AT BEST BY THEN. AT THIS
POINT...ID BE VERY SURPRISED IF ANY OF THIS ACTIVITY WILL MAKE IT
SOUTH OF KHKY/KAVL THIS EVENING...SO THERE WILL BE NO MENTION OF
CONVECTION AT KCLT OR THE UPSTATE TERMINALS.

OTHERWISE...THE OVERNIGHT FOG/LOW STRATUS POTENTIAL WILL BE THE MAIN
CONCERN. NONE OF THE TAF SITES RECEIVED MEASURABLE RAINFALL
TODAY...SO THE POTENTIAL WOULD APPEAR TO BE QUITE A BIT LOWER THAN
WAS SEEN EARLY THIS MORNING. NEVERTHELESS...PERSISTENCE IS TYPICALLY
A GOOD FORECAST AT KAVL THIS TIME OF YEAR...AND SINCE THEY HAVE
OBSERVED LIFR CONDITIONS THE PAST TWO MORNINGS...WE WILL FORECAST IT
AGAIN. OTHERWISE...MVFR FOG WILL BE ADVERTISED AT KAND AND KHKY.
MVFR CONDITIONS CANNOT BE RULED OUT ELSEWHERE...BUT CONFIDENCE IS
LOW.

CONVECTION WILL REDEVELOP FRIDAY AFTERNOON...WITH COVERAGE EXPECTED
TO BE A LITTLE HIGHER IN ADVANCE OF AN APPROACHING COLD FRONT. VCTS
WILL BE CARRIED AT ALL TERMINALS DURING THE AFTERNOON...EXCEPT FOR A
PROB30 AT KCLT AFTER 19Z.

OUTLOOK...AS A COLD FRONT STALLS OVER THE AREA...SCATTERED TO
NUMEROUS (MAINLY DIURNAL) CONVECTION AND ASSOCIATED RESTRICTIONS
WILL PERSIST THROUGH THE WEEKEND. LATE NIGHT/MORNING FOG AND LOW
STRATUS PROBABILITIES WILL ALSO REMAIN FAIRLY HIGH...ESPECIALLY IN
THE MTN VALLEYS.

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...JAT/JDL
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...JDL

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
524 PM EDT THU JUL 19 2012

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-202130-
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-
524 PM EDT THU JUL 19 2012

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

.DAY ONE...TONIGHT.

SCATTERED TO NUMEROUS THUNDERSTORMS WILL CONTINUE ACROSS THE
WESTERN CAROLINAS AND NORTHEAST GEORGIA INTO THE EVENING.

SEVERAL OF THE STORMS WILL BECOME SEVERE...PRODUCING AREAS OF WIND
DAMAGE AND LARGE HAIL. THE EFFECTS OF HEAVY DOWNPOURS AND
SATURATED SOILS WILL ENHANCE THE THREAT OF FALLING TREES.
LOCALLY VERY HEAVY RAINFALL WILL ACCOMPANY THE STORMS AND FLOODING
OF POOR DRAINAGE AREAS AND A FEW STREAMS WILL DEVELOP. THE STORMS
WILL ALSO PRODUCE FREQUENT CLOUD TO GROUND LIGHTNING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

ANOTHER ROUND OF NUMEROUS THUNDERSTORMS IS EXPECTED FRIDAY
AFTERNOON AND EVENING. CONDITIONS WILL BE SIMILAR TO THE PAST FEW
DAYS WITH SEVERAL OF THE STORMS BECOMING SEVERE...PRODUCING AREAS
OF WIND DAMAGE AND LARGE HAIL. IN ADDITION...SATURATED SOILS WILL
ENHANCE THE THREAT OF FALLING TREES. LOCALLY VERY HEAVY RAINFALL
WILL ACCOMPANY THE STORMS AND FLOODING OF POOR DRAINAGE AREAS AND
A FEW STREAMS WILL DEVELOP. THE STORMS WILL ALSO PRODUCE FREQUENT
CLOUD TO GROUND LIGHTNING.

.SPOTTER INFORMATION STATEMENT...

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

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
855 PM EDT THU JUL 19 2012

NCZ048-052-053-200200-
BUNCOMBE-HAYWOOD-MADISON-
855 PM EDT THU JUL 19 2012

...STRONG THUNDERSTORMS WILL AFFECT BUNCOMBE...MADISON AND NORTHERN
HAYWOOD COUNTIES THROUGH 1000 PM EDT...

AT 854 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 6 MILES NORTH OF
SWISS TO 3 MILES NORTHEAST OF CEDAR CREEK TO LOWLAND...MOVING SOUTH
AT 25 MPH. THESE THUNDERSTORMS WILL BRING WIND GUSTS OF 30 TO 40 MPH
ACROSS MOST OF NORTHERN HAYWOOD AND MADISON COUNTIES THROUGH 930
PM...WITH GUSTS OF 35 MPH POSSIBLY REACHING THE ASHEVILLE AREA BY 10
PM. PEA SIZE HAIL AND LOCALLY HEAVY RAINFALL WILL BE POSSIBLE AS
WELL.

LAT...LON 3604 8259 3597 8260 3598 8251 3591 8249
      3573 8228 3559 8229 3553 8217 3551 8223
      3546 8225 3550 8233 3546 8245 3551 8318
      3567 8318 3573 8324 3580 8308 3578 8299
      3595 8289 3593 8281 3601 8277 3607 8263

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
904 PM EDT THU JUL 19 2012

NCZ082-200130-
UNION-
904 PM EDT THU JUL 19 2012

...A STRONG THUNDERSTORM WILL AFFECT SOUTHERN UNION COUNTY THROUGH
930 PM EDT...

AT 904 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 7 MILES SOUTH OF WAXHAW...OR 8 MILES NORTHEAST OF
LANCASTER...MOVING EAST AT 15 MPH.

PEA SIZE HAIL...FREQUENT LIGHTNING...WIND GUSTS UP TO 40 MPH...AND
TORRENTIAL RAIN ARE EXPECTED WITH THIS STORM.

LAT...LON 3481 8079 3482 8080 3491 8080 3492 8079
      3494 8041 3481 8041

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
927 PM EDT THU JUL 19 2012

NCZ035>037-056-057-068-069-501>506-508-200230-
ALEXANDER-BURKE MOUNTAINS-CALDWELL
MOUNTAINS-CATAWBA-CLEVELAND-DAVIE-EASTERN MCDOWELL-GREATER
BURKE-GREATER CALDWELL-GREATER RUTHERFORD-IREDELL-LINCOLN-MCDOWELL
MOUNTAINS-ROWAN-
927 PM EDT THU JUL 19 2012

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT THE NORTH CAROLINA
FOOTHILLS AND NORTHWEST PIEDMONT THROUGH 1030 PM EDT...

AT 925 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM WOODLAWN TO LENOIR
TO UNION GROVE...MOVING SOUTHEAST AT 20 MPH. THESE THUNDERSTORMS
WILL IMPACT THE INTERSTATE 40 CORRIDOR AND WILL BE ACCOMPANIED BY
WIND GUSTS OF 30 TO 40 MPH...AND POSSIBLY SMALL HAIL. HEAVY RAINFALL
AND FREQUENT LIGHTNING CAN BE EXPECTED WITH THE STRONGEST
THUNDERSTORMS AS WELL.

LAT...LON 3588 8038 3588 8041 3584 8038 3582 8047
      3574 8045 3572 8039 3569 8040 3537 8182
      3584 8211 3586 8204 3588 8203 3587 8200
      3590 8198 3603 8135 3600 8132 3603 8127
      3603 8108 3607 8098 3607 8046 3596 8037

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
929 PM EDT THU JUL 19 2012

SCZ009-013-014-200200-
CHESTER-UNION-YORK-
929 PM EDT THU JUL 19 2012

...A STRONG THUNDERSTORM WILL AFFECT EASTERN UNION...NORTHWESTERN
CHESTER AND SOUTHWESTERN YORK COUNTIES THROUGH 1000 PM EDT...

AT 929 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 4 MILES SOUTHEAST OF LOCKHART...OR 12 MILES EAST
OF UNION...MOVING EAST AT 15 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  LOWRYS...

PEA SIZE HAIL...FREQUENT LIGHTNING...AND WIND GUSTS UP TO 40 MPH ARE
EXPECTED WITH THIS STORM.

LAT...LON 3490 8118 3468 8113 3464 8149 3482 8153

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
955 PM EDT THU JUL 19 2012

NCZ035-036-049-056-068>070-502>508-510-200300-
ALEXANDER-BURKE MOUNTAINS-CATAWBA-CLEVELAND-EASTERN MCDOWELL-EASTERN
POLK-GASTON-GREATER BURKE-GREATER CALDWELL-GREATER
RUTHERFORD-IREDELL-LINCOLN-MCDOWELL MOUNTAINS-RUTHERFORD
MOUNTAINS-YANCEY-
955 PM EDT THU JUL 19 2012

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT THE NORTH CAROLINA
PIEDMONT AND FOOTHILLS THROUGH 11 PM EDT THIS EVENING...

AT 953 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM TAYLORSVILLE TO
MORGANTON TO WOODLAWN...MOVING SOUTH AT 15 MPH. THESE THUNDERSTORMS
WILL PRODUCE WIND GUSTS TO 40 MPH IN SOME LOCATIONS AS WELL AS PEA
SIZE HAIL...AND LOCALLY HEAVY RAINFALL. THE THUNDERSTORMS WILL
IMPACT MAINLY LOCATIONS ALONG AND IMMEDIATELY SOUTH OF THE
INTERSTATE 40 CORRIDOR THROUGH 11 PM.

LAT...LON 3605 8104 3558 8083 3525 8139 3526 8218
      3539 8220 3540 8219 3552 8223 3553 8217
      3556 8223 3583 8228 3583 8215 3582 8214
      3583 8212 3583 8166

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1015 PM EDT THU JUL 19 2012

NCZ051-052-058-200315-
GRAHAM-HAYWOOD-SWAIN-
1015 PM EDT THU JUL 19 2012

...GUSTY WINDS FROM THUNDERSTORMS WILL IMPACT THE GREAT SMOKY
MOUNTAINS THROUGH 1130 PM EDT...

AT 1013 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS ALONG A LINE EXTENDING FROM 3 MILES NORTH OF COSBY TO
GATLINBURG TO 3 MILES NORTH OF WILDWOOD...MOVING SOUTH AT 25 MPH.
THESE THUNDERSTORMS HAVE A HISTORY OF PRODUCING 30 TO 40 MPH WIND
GUSTS...AND THESE GUSTY WINDS WILL LIKELY MOVE ACROSS
GRAHAM...SWAIN...AND NORTHERN HAYWOOD COUNTIES THROUGH 1130 PM.

LAT...LON 3537 8401 3541 8403 3553 8388 3553 8383
      3557 8377 3557 8349 3567 8334 3566 8330
      3573 8324 3573 8321 3577 8316 3579 8307
      3555 8301 3549 8315 3552 8325 3546 8336
      3541 8335 3528 8364 3529 8393 3535 8404

HG