Special Weather Statement, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
251 PM EDT SAT JUL 12 2014

.SYNOPSIS...
WEAK HIGH PRESSURE WILL LINGER OVER THE WESTERN CAROLINAS AND
NORTHEAST GEORGIA THE REST OF THE WEEKEND. AN UNSEASONABLY STRONG
COLD FRONT WILL APPROACH THE AREA FROM THE NORTHWEST ON MONDAY AND
CROSS THE REGION TUESDAY. COOLER THAN NORMAL TEMPERATURES WILL
ARRIVE FROM MID TO LATE WEEK BEHIND THE FRONT.

&&

.NEAR TERM /THROUGH SUNDAY/...
AT 245 PM EDT SATURDAY... CURRENT MESOANALYSIS INDICATES CAPES OVER
THE MOUNTAINS ARE AROUND 1500 J/KG AND GENERALLY LESS THAN 1000 J/KG
EAST OF THE MOUNTAINS. RAP FORECAST INTO THE EVENING SHOWS CAPE
PERSISTS FOR A WHILE IN THE FAR WESTERN ZONES... ALIGNED WITH THE
AXIS OF HIGH TERRAIN... BUT CAPE DECREASES SUBSTANTIALLY IN THE
EAST. AS HAS BEEN THE CASE DURING THE PAST COUPLE OF NIGHTS...
ISOLATED CONVECTIVE STORMS MIGHT CONTINUE WELL AFTER SUNSET. VERY
LIGHT WINDS THROUGH A DEEP LAYER COULD RESULT IN SLOWLY MOVING
THUNDERSTORMS AND THE POTENTIAL FOR LOCALLY EXCESSIVE RAINFALL.
OTHERWISE... PRIMARY FEATURE ALOFT AFFECTING OUR WEATHER THROUGH
SUNDAY IS A RIDGE EXTENDING FROM THE WEST COAST ACROSS THE SOUTHERN
STATES TO THE CAROLINAS. AT THE SURFACE... HIGH PRESSURE WITH A VERY
WEAK GRADIENT WILL COVER THE REGION. AS HEIGHTS FALL OVER THE
NORTHERN U.S. ON SUNDAY... THE EASTERN PERIPHERY OF THE UPPER LEVEL
RIDGE WILL WITHDRAW WESTWARD A BIT... BUT THROUGH TOMORROW THE RIDGE
IS GOING TO BE THE PRIMARY PLAYER IN CONTINUING THE CURRENT PERIOD
OF GENERALLY TRANQUIL WEATHER. THE AIR MASS OVER THE WESTERN ZONES
WILL REMAIN FAIRLY MOIST AND MODERATELY UNSTABLE THUS SUPPORTING
SCATTERED SHOWERS AND THUNDERSTORMS WHICH WILL BE MOST NUMEROUS OVER
THE HIGHER TERRAIN. CAPE VALUES EAST OF THE MOUNTAINS ON SUNDAY WILL
BE HELD AT BAY BY A RATHER WARM TEMPERATURE PROFILE. AN ISOLATED
SHOWER OR THUNDERSTORM IS POSSIBLE... BUT CUMULUS AND TOWERING
CUMULUS SHOULD DOMINATE THE SKY IN OUR PIEDMONT ZONES TOMORROW. LOWS
WILL BE AROUND 70 IN THE PIEDMONT AND IN THE 60S IN THE MOUNTAINS.
HIGHS ON SUNDAY WILL BE FAIRLY CLOSE TO NORMAL... PERHAPS A FEW
DEGREES ABOVE NORMAL AT A FEW LOCATIONS. HIGHS WILL BE AROUND 90
EAST OF THE MOUNTAINS AND IN THE LOWER AND MID 80S IN THE MOUNTAIN
VALLEYS.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AS OF 230 PM EDT SATURDAY...THE SHORT RANGE PERIOD INITIALIZES
SUNDAY EVENING WITH A BROAD LONGWAVE UPPER TROF ROTATING ACROSS
SOUTHERN ONTARIO.  MEANWHILE...BERMUDA HIGH WILL CONTINUE TO ADVECT
WARM/MOIST AIR ACROSS THE SOUTHEAST...NORTHWARD INTO THE MID
ATLANTIC STATES.  EXPECTING ONGOING CONVECTION ACROSS THE HIGH
TERRAIN AT FORECAST INITIALIZATION DUE TO IMPROVED INSTABILITY AXIS
AND WEAK SOUTHERLY UPSLOPE FLOW.   CHANCE LEVEL POPS WILL BE
FEATURED INITIALLY ACROSS THE HIGH TERRAIN BEFORE TAPERING DOWN TO
SLIGHT CHANCE LEVELS BY DAYBREAK.  BY MONDAY MORNING...THE
FIRST...AND WEAKER OF TWO COLD FRONTAL BOUNDARIES WILL APPROACH THE
REGION FROM THE WEST.  ADJACENT WEAK UPPER IMPULSE COMBINED WITH
BOUNDARY INTRUSION WILL SPAWN CONVECTION ACROSS THE
MOUNTAINS/FOOTHILLS DURING THE AFTERNOON HOURS ON MONDAY.  DUE TO
THE SUSTAINED SOUTHERLY FLOW IN DAYS PAST...THE ATMOSPHERE WILL HAVE
RECOVERED ENOUGH TO YIELD A MODERATELY UNSTABLE WARM SECTOR AHEAD OF
THIS FRONT.  THUS...EXPECTING SHOWERS AND THUNDERSTORMS TO SPILL OUT
OF THE HIGH TERRAIN AND PROPAGATE EAST INTO THE PIEDMONT/FOOTHILLS
MONDAY EVENING.  AS SAID ABOVE...SUBSTANTIAL CAPE WILL BE PRESENT TO
SUPPORT SOME DEEPER UPDRAFTS LEADING TO A FEW STRONG/SEVERE
THUNDERSTORMS MONDAY AFTERNOON/EVENING...DESPITE WEAKER YET
IMPROVING SHEAR.  FORECAST WILL FEATURE LIKELY POPS ACROSS THE
MAJORITY OF THE MOUNTAIN/FOOTHILLS ZONES WHILE LOWER CHANCE POPS ARE
HIGHLIGHTED SOUTH EASTWARD ACROSS NORTHEAST GA AND THE NC/SC
PIEDMONTS.

TUESDAY MORNING THE ABOVE MENTIONED BOUNDARY WILL HAVE ESSENTIALLY
DISSIPATED AND BECOME STATIONARY ACROSS CENTRAL NC...SOUTHWARD
INTO THE MIDLANDS OF SC.  AT THE SAME TIME THE RATHER
DEEP/IMPRESSIVE UPPER LOW WILL ROTATE DOWN ACROSS THE GREAT LAKES
WHILE SURFACE CYCLOGENESIS OCCURS ALONG THE EASTERN SEABOARD.  THE
STRONG COLD FRONT WILL BE PUSHING THROUGH THE OHIO VALLEY BY EARLY
MORNING...EASTWARD INTO THE CENTRAL/SOUTHERN APPS BY MID/LATE
MORNING...THEN FINALLY FURTHER EAST INTO THE PIEDMONT REGIONS ON
TUESDAY AFTERNOON/EVENING.  EXPECTING THE ABOVE MENTIONED SURFACE
CYCLONE TO DEEPEN SLIGHTLY AND AID IN DEVELOPMENT OF A LEE SIDE
TROF ACROSS THE PIEDMONT/COASTAL PLAINS OF NC LATE IN THE
AFTERNOON.  THIS WEAK/DIFFUSE BOUNDARY COULD PROVIDE A FOCUS FOR
SURFACE CONVERGENCE AHEAD OF THE APPROACHING/STRONG COLD FRONT.
THERE WILL BE SUFFICIENT UPPER SUPPORT...SHEAR...AND BUOYANCY IN
PLACE TO SUPPORT ORGANIZED STRONG/SEVERE CONVECTION ACROSS THE
ENTIRE REGION ON TUESDAY.  THE FORECAST WILL FEATURE WIDESPREAD
LIKELY POPS FOR TUESDAY ENCOMPASSING THE ENTIRE REGION.  WILL
CONTINUE WITH SEVERE THUNDERSTORM POSSIBLE WORDING IN THE HWO FOR
BOTH MONDAY EVENING/OVERNIGHT...AND THROUGH THE DAY ON TUESDAY.
TEMPERATURES WILL BE ABOVE NORMAL ON MONDAY AS DEEP SOUTHERLY FLOW
PREVAILS AMONGST PARTLY CLOUDY SKIES WHILE MOSTLY CLOUDY SKIES
COMBINE WITH PRECIPITATION TO KEEP HIGHS A FEW DEGREES BELOW NORMAL
FOR TUESDAY.  BY WEDNESDAY MORNING...THE FRONT WILL BE EXITING TO
THE EAST ALLOWING FOR POPS TO TREND DOWN...ALONG WITH TEMPS.  LOWS
ON WEDNESDAY MORNING WILL REMAIN AT OR JUST BELOW NORMAL ACROSS THE
LOWER TERRAIN WHERE THE FROPA OCCURS LATER...WHILE THE HIGH TERRAIN
WILL SEE LOWS ON THE ORDER OF 5 DEGREES BELOW NORMAL.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 130 PM SAT...A BROAD TROUGH WILL BE IN PLACE ACROSS THE ERN
TWO THIRDS OF THE CONUS ON WED AS A DEEP LOW PRESSURE SYSTEM SPINS
OVER ERN CANADA AND THE NRN GREAT LAKES. DEEP LAYER DRYING IS
EXPECTED ON WEDNESDAY BEHIND THE SLOWLY DEPARTING/STALLING COLD
FRONT...WITH MAINLY NW FLOW ACROSS THE REGION. WEAK SFC HIGH PRES
WILL BUILD OVER FROM THE N...AND MAX TEMPS SHOULD DIP TO TWO
CATEGORIES BELOW NORMAL BY WED AFTN. AS THE WEAK HIGH SETTLES INTO
PLACE TO OUR N...LOW LEVEL EASTERLY FLOW COULD DEVELOP INTO THE SRN
APPALACHIANS BY THU. IT IS QUESTIONABLE HOW MUCH MOISTURE WILL
RETURN TO THE PROFILES...BUT SLIGHTLY IMPROVED BL RH COULD HELP
TRIGGER ISOLD TO SCT AFTN SHOWERS...ESPECIALLY IN AND NEAR THE MTNS.
MAX TEMPS LOOK TO BE A SOLID 5 TO 10 DEGREES BELOW NORMAL THU
AFTN...POSSIBLY MORE IF WE CLOUD UP QUICKER.

THOUGH SUBTLE MODEL DIFFERENCES EXIST BY LATE WEEK...THERE IS
REASONABLE CONSENSUS REGARDING SHORTWAVE ENERGY DIVING THROUGH THE
SRN PLAINS INTO THE BROAD TROUGH ON THU...AND THEN MOVING TO THE
BASE OF THE SRN APPALACHIANS BY FRI. THIS MAY BRING A WEAK SFC
REFLECTION AND ADDITIONAL MOISTURE BACK TO THE REGION...INTERACTING
WITH THE WEAK SFC HIGH TO THE NORTH AND POSSIBLY PROVIDING SOME
DEGREE OF COLD AIR DAMMING FRI INTO SAT. WILL KEEP MAXES WELL BELOW
NORMAL DURING THIS PERIOD...WITH MAINLY CHC POPS...HIGHEST NEAR THE
BLUE RIDGE.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
AT KCLT... SCATTERED TO BROKEN CU AND TCU 4-6K WILL CONTINUE THROUGH
THE AFTERNOON THEN GRADUALLY DISSIPATE AROUND SUNSET. VISIBILITY
UNRESTRICTED EXCEPT 5 MILES IN HAZE NEAR SUNRISE. BY MID TO LATE
MORNING SUNDAY... SCATTERED CU 4-6K FT WILL DEVELOP AND VISIBILITY
WILL BECOME UNRESTRICTED. SURFACE WIND WILL REMAIN LIGHT SOUTHEAST
BECOMING LIGHT AND VARIABLE OVERNIGHT.

ELSEWHERE... SCATTERED TO BROKEN CU AND TCU 4-6K WILL PTHROUGH THE
AFTERNOON THEN GRADUALLY DISSIPATE AFTER SUNSET. MODEL PROFILES
INDICATE VERY LITTLE CAPE AVAILABLE FOR STRONG UPDRAFTS EXCEPT OVER
THE MOUNTAINS WHERE WIDELY SCATTERED THUNDERSTORMS ARE POSSIBLE.
ISOLATED THUNDERSTORMS COULD PERSIST UNTIL MIDNIGHT. CONVECTIVE
STORMS WILL BE MOST NUMEROUS NORTH AND WEST OF KAVL... SO WILL NOT
INCLUDE IN TAF UNLESS OCCURRENCE BECOMES MORE LIKELY. VALLEY FOG
LIKELY TO BEGIN FORMING AFTER 06Z WHICH WILL RESULT IN LIFR AT KAVL.
VISIBILITY EXPECTED TO BECOME UNRESTRICTED AT KAVL BY 14Z.

OUTLOOK...RESTRICTIONS IN THUNDERSTORMS ARE POSSIBLE MONDAY AND
TUESDAY. UNLIMITED CEILING AND UNRESTRICTED VISIBILITY WILL RETURN
ON WEDNESDAY FOLLOWING COLD FRONTAL PASSAGE.

CONFIDENCE TABLE...

            19-01Z        01-07Z        07-13Z        13-19Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH  83%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH  83%
KAVL       HIGH  92%     HIGH  91%     MED   73%     MED   74%
KHKY       HIGH 100%     HIGH 100%     HIGH  97%     HIGH  83%
KGMU       HIGH 100%     HIGH 100%     HIGH 100%     HIGH  83%
KAND       HIGH 100%     HIGH 100%     HIGH  88%     HIGH  80%

THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)

WWW.WEATHER.GOV/GSP/AVIATION_TABLES

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

&&

SYNOPSIS...HG
NEAR TERM...LGL
SHORT TERM...CDG
LONG TERM...HG
AVIATION...LGL

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1007 AM EDT SAT JUL 12 2014

GAZ010-017-018-NCZ033-048>053-058-059-062>065-501>510-SCZ001>003-
131415-
RABUN-HABERSHAM-STEPHENS-AVERY-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-
BUNCOMBE-GRAHAM-NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA-
HENDERSON-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-
1007 AM EDT SAT JUL 12 2014

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

.DAY ONE...TODAY AND TONIGHT.

WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND
EVENING. THE MAIN THREAT WILL BE LIGHTNING.

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

..SUNDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..MONDAY...SEVERE THUNDERSTORMS POSSIBLE. A COLD FRONT WILL BE
ACCOMPANIED BY THUNDERSTORMS THAT MAY PRODUCE LARGE HAIL AND
DAMAGING WIND.
..TUESDAY...SEVERE THUNDERSTORMS POSSIBLE.
..WEDNESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..THURSDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..FRIDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

GAZ026-028-029-NCZ035>037-056-057-068>072-082-SCZ004>014-019-131415-
FRANKLIN-HART-ELBERT-ALEXANDER-IREDELL-DAVIE-CATAWBA-ROWAN-CLEVELAND-
LINCOLN-GASTON-MECKLENBURG-CABARRUS-UNION NC-GREATER OCONEE-
GREATER PICKENS-GREATER GREENVILLE-SPARTANBURG-CHEROKEE-YORK-
ANDERSON-ABBEVILLE-LAURENS-UNION SC-CHESTER-GREENWOOD-
1007 AM EDT SAT JUL 12 2014

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

.DAY ONE...TODAY AND TONIGHT.

HAZARDOUS WEATHER IS NOT EXPECTED AT THIS TIME.

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

..SUNDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..MONDAY...SEVERE THUNDERSTORMS POSSIBLE. A COLD FRONT WILL BE
ACCOMPANIED BY THUNDERSTORMS THAT MAY PRODUCE LARGE HAIL AND
DAMAGING WIND.
..TUESDAY...SEVERE THUNDERSTORMS POSSIBLE.
..WEDNESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..THURSDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..FRIDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

LGL

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1200 PM EDT SAT JUL 12 2014

NCZ048-121645-
MADISON-
1200 PM EDT SAT JUL 12 2014

...A STRONG THUNDERSTORM WILL AFFECT MADISON COUNTY THROUGH 1245 PM
EDT...

AT 1200 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR HOT SPRINGS...OR 9 MILES WEST OF
MARSHALL...MOVING SOUTHEAST AT 5 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  MARSHALL...

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

LAT...LON 3593 8282 3594 8280 3579 8256 3573 8267
      3573 8271 3570 8276 3569 8282 3570 8286
      3581 8296 3584 8292 3589 8291 3595 8284

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
320 PM EDT SAT JUL 12 2014

NCZ033-501-122000-
AVERY-CALDWELL MOUNTAINS-
320 PM EDT SAT JUL 12 2014

...A CLUSTER OF STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN
CALDWELL AND AVERY COUNTIES THROUGH 400 PM EDT...

AT 313 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR SEVEN DEVILS...OR 6 MILES NORTHEAST OF
NEWLAND...MOVING SOUTHEAST AT 15 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  LINVILLE...
  GLOBE...

TORRENTIAL RAINFALL IS EXPECTED WITH THIS STORM. RAINFALL AMOUNTS OF
1 TO 2 INCHES...WITH LOCAL AMOUNTS UP TO 3 INCHES. WINDS COULD GUST
UP TO 30 MPH.

HEAVY RAINS MAY FLOOD AREAS WITH POOR DRAINAGE...SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS. WATER
LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE RAPIDLY. SEEK HIGHER
GROUND IF THREATENED BY FLOOD WATERS.

LAT...LON 3621 8190 3619 8184 3616 8182 3612 8181
      3613 8165 3609 8159 3592 8175 3616 8201
      3628 8191 3628 8189

STUREY