Special Weather Statement, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
311 PM EDT MON MAR 18 2013

.SYNOPSIS...
A STRONG COLD FRONT WILL SWEEP ACROSS THE REGION TONIGHT...USHERING
IN DRY AIR FOR TUESDAY THROUGH THURSDAY. EXPECT UNSETTLED WEATHER TO
RETURN TO THE SOUTHEAST STATES THIS WEEKEND AND INTO EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TUESDAY/...
AS OF 230 PM ...THE WEDGE CONTINUES TO HOLD FIRM WITH LOWS CLOUDS
AND AREAS OF MAINLY DRIZZLE EAST OF THE MOUNTAINS. RADAR IS SHOWING
SHOWERS BECOMING MORE WIDESPREAD OVER THE MOUNTAINS...AND A FEW
THUNDERSTORMS MAY ALSO HOLD TOGETHER TO AFFECT FAR WESTERN NC AND
THE THE TN BORDER COUNTIES BY 4 PM.  THIS IS ALL HANDLED WELL IN THE
GRIDS AT THE MOMENT. TEMPS REMAIN QUITE COOL WITH LOW TO MID 40S
WIDESPREAD...EXCEPT SOME LOW TO MID 50S ON THE FRINGES OF THE WEDGE
IN THE FAR W AND S.

MODELS INDICATE THAT THE WEDGE WILL HOLD TOUGH AT LEAST THROUGH 06Z
AND REALLY NOT WASH OUT UNTIL AFTER THE PASSAGE OF A COLD FRONT
BEGINNING AROUND MIDNIGHT IN THE MOUNTAINS...AND LATE TONIGHT IN THE
FAR EASTERN COUNTIES. MESO MODELS LIKE THE HRRR AND OUR LOCAL WRF
INDICATE THAT THE MAIN AREA OF SHOWERS ASSOCIATED WITH A PASSING
UPPER WAVE WILL AFFECT THE AREA FROM MID AFTERNOON INTO EARLY
EVENING AND THEN SHIFT TO THE EAST OF THE AREA. ANOTHER BAND OF
SHOWERS IS THEN FORECAST TO ACCOMPANY THE COLD FRONT...BUT MAY BE
MORE SCATTERED EAST OF THE MOUNTAINS. SBCAPES REMAIN QUITE LOW OR
NON-EXISTANT DUE TO THE WEDGE...BUT MUCAPES APPEAR SUFFICIENT FOR
SOME ELEVATED THUNDER ALONG THE SOUTHERN AND WESTERN BOUNDARIES OF
THE WEDGE MODIFIED AIR. TEMPERATURES OVERNIGHT WILL REMAIN GENERALLY
STEADY OR EVEN SLOWLY RISE AS WEDGE SLOWLY ERODES. USED A BLEND OF 3
HOURLY MOS NUMBERS TO TRY AND CAPTURE THE TEMP TREND.

DEEP LAYER DRYING IS FORECAST TO OCCUR ON TUE BEHIND THE COLD FRONT
AS THE UPPER FLOW BECOMES ZONAL BEHIND THE DEPARTING UPPER WAVE AND
SURFACE HIGH PRESSURE RIDGES EAST. DOWNSLOPE FLOW ON TUE WILL
COUNTER COLD ADVECTION TO A LARGE EXTENT...AND WITH PLENTY OF
SUNSHINE TEMPS ARE FORECAST TO CLIMB WELL INTO THE 60S OUTSIDE THE
MOUNTAINS...WITH 50S IN THE MOUNTAIN VALLEYS. USED MOS BLEND TO
GENERATE TEMPS.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 250 PM MONDAY...MODELS CONTINUE TO SHOW A CHANNELED SHORT WAVE
ROTATING AROUND A LARGE UPR LVL VORTEX OVR THE GREAT LAKES/SRN
QUEBEC LATE WED AND WED NITE. THE GUIDANCE ALSO HAS A WEAKER SHORT
WAVE MOVING ALONG THE GULF COAST DURING THIS TIME. AT THE SFC...
THESE WAVES LEAD TO A DOUBLE-BARRELED LOW PRESSURE SYSTEM...ONE NRN
STREAM CLIPPER AND A SRN STREAM FAST MOVING GULF COAST LOW. SOME OF
THE GUIDANCE IS NOW DEVELOPING LIGHT PRECIP WITH THE SRN STREAM LOW.
HOWEVER...THE LOW LEVELS REMAIN QUITE DRY...SO EXPECT NO MORE THAN
MOSTLY CLOUDY SKIES FROM MAINLY MID AND HIGH LEVEL CLOUDS. MDLS
STILL SHOWING THE NRN STREAM CLIPPER PRODUCING LIGHT PRECIP ACROSS
MAINLY THE TN BORDER COUNTIES OF THE NC MTNS. TEMPS AND THICKNESSES
HAVE COME IN QUITE COLDER WITH THESE SYSTEMS. THEREFORE...IT APPEARS
THAT ANY PRECIP ACROSS THE MTNS WILL BE MAINLY SNOW SHOWERS...
POSSIBLY MIXED WITH RAIN AT ONSET. GUIDANCE BLEND OF QPF SUGGESTING
UP TO AN INCH OF SNOW POSSIBLE ACROSS THE USUAL AREAS OF THE NRN
MTNS. IF SOMETHING WAS TO FALL OUTSIDE OF THE MTNS...IT WOULD BE
SPRINKLES OR FLURRIES. SUSTAINED WINDS HAVE COME IN LOWER ON THE
LATEST GUIDANCE FOR WED...BUT IT SHOULD STILL BE BREEZY WITH GUSTY
WINDS.

LOWS TUE NITE 5 TO 10 DEGREES BELOW NORMAL ACROSS THE MTNS AND A FEW
DEGREES BELOW NORMAL ELSEWHERE. THE 20TH IS THE FIRST DAY OF SPRING
WHICH IS THE START OF THE FROST/FREEZE PROGRAM OUTSIDE OF THE MTNS
FOR OUR CWFA. I DO HAVE SOME AREAS AROUND FREEZING. HOWEVER...WILL
HOLD OFF ON A FREEZE WATCH AS THERE WILL BE QUITE A BIT OF MID AND
HIGH CLOUDS THAT SHUD KEEP TEMPS FROM FALLING DRAMATICALLY. HIGHS
WED AROUND 5 DEGREES BELOW NORMAL

SKIES CLEAR OUTSIDE OF THE MTNS LATE WED NITE AND OVER THE MTNS THU.
LOWS AROUND 10 DEGREES BELOW NORMAL. SHUD THIS TREND CONTINUE...THEN
A FREEZE WARNING WOULD BE NEEDED FOR MUCH OF THE CWFA OUTSIDE OF THE
MTNS. LOOKS TO BE A BREEZY AND POSSIBLY WINDY DAY THU WITH GUSTY
WINDS AGAIN. HIGHS WILL BE 10 TO 15 DEGREES BELOW NORMAL WITH THE
COLD AIR MASS MOVING IN.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 220 PM TUESDAY...DIFFERENCES SEEN IN THE MEDIUM RANGE MODELS
IN TIMING AND LOCATION OF LOW DEVELOPMENT. THIS PERIOD BEGINS AT 00Z
FRIDAY AND AT THAT TIME THE GFS AND ECMWF AGREE ON LOCATION OF UPPER
LOW OVER QUEBEC AND THE DEPARTING WEAK SURFACE HIGH OVER THE
CAROLINAS. FAIRLY GOOD INFLOW FROM THE GULF ON FRIDAY AHEAD OF THE
LOW OVER EAST TEXAS.  ALTHOUGH THERE IS SOME GENERAL AGREEMENT ON
LOWS CROSSING THE SOUTHEAST STATES...THE CANADIAN IS CLOSER TO THE
ECMWF AND THE GFS CREATES A VASTLY DIFFERENT SOLUTION ON THE LOW
DEVELOPMENT OVER TENNESSEE SATURDAY NIGHT INTO SUNDAY. THE GFS SETS
UP A BETTER COLD AIR WEDGE SATURDAY INTO SATURDAY
NIGHT...HOWEVER...THE CENTER OF THE HIGH WILL BE FAR NORTH IN
CANADA.  THE GFS DEVELOPS A DEEP LOW NEAR MEMPHIS LATE SATURDAY AND
TRACKS IT EAST CROSSING THE NC MTNS LATE SUNDAY. KEEPING A DIURNAL
PRECIP TRANSITION FOR THE MTNS AND NC FOOTHILLS WITH NIGHT TIME SNOW
AND DAYTIME RAIN AS SOUNDINGS TRENDING TOWARD EITHER RAIN OR SNOW.
BOTH GFS AND ECMWF DEVELOP AND COASTAL LOW TO START THE NEW WEEK
WITH THE FIRST LOW GIVING ITS ENERGY TO THE NEW LOW ON THE NC COAST
AND THIS MOVES EAST OVER THE ATLANTIC. DRYING TO OCCUR AT THE END OF
THE CURRENT SEVEN DAY WITH HIGH PRESSURE CROSSING THE PLAINS.
DAYTIME HIGHS THROUGH THIS MEDIUM RANGE AT LEAST TEN DEGREES BELOW
NORMAL AND NIGHT TIME LOWS 2 TO 5 DEGREES BELOW NORMAL DUE TO THE
CLOUD COVER.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
AT KCLT...COLD AIR WEDGE HAS LOCKED INTO THE AREA WITH CIGS HOLDING
STEADY AROUND 005OVC. AREAS OF DRIZZLE/FOG CAUSING SOME VSBY
RESTRICTIONS AS WELL. CURRENT INDICATIONS ARE THAT THERE WILL BE
LITTLE CHANGE IN THE OVERALL CONDITIONS UNTIL AFTER A COLD FRONT
MOVES THROUGH LATE TONIGHT WHICH WILL SHIFT WINDS TO THE NW. EXPECT
A WAVE OF SHOWERS TO AFFECT THE AIRFIELD THIS EVENING CAUSING VSBY
RESTRICTIONS...WITH FOG KEEPING VSBYS LOW AFTERWARD UNTIL LATE
TONIGHT. EXPECT RAPID CLEARING AFTER 12Z ON TUE.

ELSEWHERE...THE REST OF THE REGION IS SHARING IN THE COLD AIR
DAMMING CONDITIONS. THIS MEANS GENERALLY IFR TO LIFR CIGS THROUGH
MOST OF TONIGHT. A WAVE OF SHOWERS WILL MOVE ACROSS THE AREA THIS
AFTERNOON INTO THIS EVENING RESTRICTING VSBYS. FOG WILL CONTINUE TO
THE RESTRICT VSBYS UNTIL AFTER A COLD FORNT MOVES THROUGH LATE
TONIGHT. EXPECT CLEARING EARLY TUE MORNING. THE ONLY AIRFIELD WHERE
THUNDER IS MENTIONED IS AT KAND AS WEDGE BOUNDARY WILL BE CLOSEST
THERE.

OUTLOOK...GENERALLY VFR CONDITIONS ARE EXPECTED THROUGH THURSDAY.

CONFIDENCE TABLE...

            19-01Z        01-07Z        07-13Z        13-19Z
KCLT       MED   75%     MED   74%     MED   70%     HIGH  84%
KGSP       MED   74%     MED   75%     MED   61%     HIGH  94%
KAVL       HIGH  83%     MED   71%     MED   68%     HIGH 100%
KHKY       HIGH  84%     MED   74%     MED   69%     HIGH  92%
KGMU       MED   77%     MED   72%     MED   64%     HIGH  94%
KAND       MED   75%     MED   77%     MED   65%     HIGH  94%

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

&&

.FIRE WEATHER...
A WARM...DRY AND WINDY AIR MASS WILL MOVE IN TUE BEHIND A DEPARTING
COLD FRONT. MINIMUM RH VALUES WILL BE LESS THAN 25 PERCENT ACROSS
MUCH OF THE AREA WITH GUSTY WINDS DEVELOPING. ALTHOUGH FUEL MOISTURE
IS RELATIVELY HIGH AND PRECIP MOVES ACROSS THE AREA TONIGHT...NC
FOREST SERVICE IS CONCERNED ABOUT THE DRYING AND DEVELOPING WINDS.
THEREFORE...A FIRE DANGER STATEMENT WILL BE ISSUED FOR TUE. SC LAND
MANAGERS ARE NOT AS CONCERNED FOR THE UPSTATE AND NE GA FUEL
MOISTURE WAS NEAR 20 PERCENT MON AFTERNOON. THEREFORE...NO STATEMENT
FOR SC OR GA. BREEZY AND GUSTY CONDITIONS RETURN WED AFTERNOON WITH
ANOTHER DAY OF VERY LOW RH VALUES. FIRE DANGER STATEMENTS MAY BE
NEEDED THEN AS WELL.

&&

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

&&

SYNOPSIS...DEO
NEAR TERM...LG
SHORT TERM...RWH
LONG TERM...DEO
AVIATION...LG
FIRE WEATHER...RWH

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
509 AM EDT MON MAR 18 2013

NCZ035>037-049-050-053-056-057-063>065-068>072-082-502-504>510-
SCZ002-003-005>009-013-014-190915-
ALEXANDER-IREDELL-DAVIE-YANCEY-MITCHELL-BUNCOMBE-CATAWBA-ROWAN-
SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-CLEVELAND-LINCOLN-GASTON-
MECKLENBURG-CABARRUS-UNION NC-GREATER CALDWELL-GREATER BURKE-
MCDOWELL MOUNTAINS-EASTERN MCDOWELL-RUTHERFORD MOUNTAINS-
GREATER RUTHERFORD-POLK MOUNTAINS-EASTERN POLK-PICKENS MOUNTAINS-
GREENVILLE MOUNTAINS-GREATER PICKENS-GREATER GREENVILLE-SPARTANBURG-
CHEROKEE-YORK-UNION SC-CHESTER-
509 AM EDT MON MAR 18 2013

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

.DAY ONE...TODAY AND TONIGHT.

A COOL...STABLE AIRMASS WILL REMAIN IN PLACE TODAY OVER MUCH OF
THE FOOTHILLS AND PIEDMONT OF WESTERN NORTH AND SOUTH CAROLINA...AS
WELL AS THE CENTRAL AND NORTHERN MOUNTAINS. HOWEVER...BY LATE
AFTERNOON AND INTO THE EVENING HOURS A FEW THUNDERSTORMS COULD
STILL DEVELOP. THE MAIN THREAT FROM THESE STORMS WILL BE CLOUD TO
GROUND LIGHTNING AND LOCALLY HEAVY RAIN.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

GAZ010-017-018-026-028-029-NCZ048-051-052-058-059-062-SCZ001-004-
010>012-019-190915-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-MADISON-SWAIN-HAYWOOD-
GRAHAM-NORTHERN JACKSON-MACON-OCONEE MOUNTAINS-GREATER OCONEE-
ANDERSON-ABBEVILLE-LAURENS-GREENWOOD-
509 AM EDT MON MAR 18 2013

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

.DAY ONE...TODAY AND TONIGHT.

SCATTERED THUNDERSTORMS ARE EXPECTED TO MOVE INTO THE AREA FROM
THE TENNESSEE VALLEY THIS AFTERNOON AND EVENING. A FEW OF THE
STORMS COULD BECOME SEVERE OVER THE FAR WESTERN MOUNTAINS OF NORTH
CAROLINA...EXTREME NORTHEAST GEORGIA...AND WESTERN AND SOUTHERN
PORTIONS OF THE UPSTATE.

BY LATE AFTERNOON A WARM FRONT MAY LIFT AS FAR NORTH AS
ELBERT...GREENWOOD AND ABBEVILLE COUNTIES. THE AIRMASS SOUTH OF
THE FRONT WILL BE WARM AND UNSTABLE. IN FACT...THERE WILL BE
ADEQUATE SHEAR AND INSTABILITY TO SUPPORT A FEW SUPERCELL
THUNDERSTORMS. IF ONE OF THESE STORMS MOVES ALONG OR JUST SOUTH OF
THE WARM FRONT...IT COULD SPAWN A BRIEF TORNADO. OTHERWISE...LARGE
HAIL WILL BE THE MAIN THREAT FROM SEVERE STORMS TODAY.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

NCZ033-501-503-190915-
AVERY-CALDWELL MOUNTAINS-BURKE MOUNTAINS-
509 AM EDT MON MAR 18 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN NORTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT.

PATCHY FREEZING RAIN AND FREEZING DRIZZLE WILL FALL ACROSS PARTS OF
AVERY COUNTY AS WELL AS THE HIGHER ELEVATIONS OF BURKE AND
CALDWELL COUNTIES THIS MORNING. A GLAZE OF ICE IS POSSIBLE ON
ELEVATED SURFACES.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

MCAVOY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
343 PM EDT MON MAR 18 2013

NCZ033-035>037-048>053-056>059-062>065-068>072-082-501>510-191100-
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-
343 PM EDT MON MAR 18 2013

...INCREASED FIRE DANGER FROM TUESDAY AFTERNOON THROUGH
TUESDAY EVENING...

A COLD FRONT WILL MOVE ACROSS THE AREA TONIGHT. A WARM AND DRY AIR
MASS WILL MOVE IN BEHIND THE FRONT ON TUESDAY. THIS WILL RESULT IN
AFTERNOON RELATIVE HUMIDITY VALUES BELOW 25 PERCENT ACROSS MUCH OF
WESTERN NORTH CAROLINA. WINDS WILL INCREASE INTO THE 10 TO 2O MPH
RANGE WITH GUSTS AS HIGH AS 35 MPH. EVEN WITH THE EXPECTED
PRECIPITATION TONIGHT...LAND MANAGERS ARE CONCERNED WITH RAPIDLY
DRYING FUELS FROM THE DRY AND BREEZY CONDITIONS TUESDAY.
THEREFORE...INCREASED FIRE DANGER IS ANTICIPATED.

PLEASE REFER TO YOUR LOCAL BURN PERMITTING AUTHORITIES ON WHETHER
YOU CAN BURN TODAY. IF YOU DO BURN...USE EXTREME CAUTION SINCE
FIRES CAN QUICKLY GET OUT OF HAND UNDER THESE CONDITIONS.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
403 PM EDT MON MAR 18 2013

NCZ065-509-SCZ002-003-182030-
GREENVILLE MOUNTAINS-HENDERSON-PICKENS MOUNTAINS-POLK MOUNTAINS-
403 PM EDT MON MAR 18 2013

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN GREENVILLE...NORTHERN
PICKENS...SOUTHERN HENDERSON AND SOUTHWESTERN POLK COUNTIES THROUGH
430 PM EDT...

AT 402 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR TABLE ROCK RESERVOIR...OR 12 MILES NORTH OF
PICKENS...MOVING NORTHEAST AT 60 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  CAESARS HEAD...
  JONES GAP STATE PARK...
  NORTH SALUDA RESERVOIR...

PEA SIZE HAIL 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 3515 8222 3513 8222 3495 8272 3507 8278
      3507 8276 3508 8278 3507 8276 3510 8272
      3510 8270 3513 8268 3512 8266 3514 8258
      3517 8259 3529 8231

08