High Wind Watch 1, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
259 PM EST WED JAN 1 2014

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE REGION...BEFORE A COLD FRONT
CROSSES THE FROM THE WEST ON THURSDAY. STRONG AND COLD CANADIAN HIGH
PRESSURE WILL THEN BUILD ACROSS THE AREA FRIDAY AND SLOWLY SHIFT
EAST THROUGH THE WEEKEND. ANOTHER COLD FRONT WILL APPROACH THE
CAROLINAS EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH THURSDAY/...
AT 230 PM EST WEDNESDAY...A SOUTHERN STREAM SHORTWAVE WILL WEAKEN
THIS EVENING AS IT LIFTS NE OUT OF AN UPPER TROUGH W OF THE MS RIVER
VALLEY. CIRRUS STREAMING EAST OVER A DOWNSTREAM RIDGE WILL CONTINUE
TO CROSS OUR AREA...AS SHOWN IN MODEL TIME HEIGHTS. THE UPPER TROUGH
WILL AMPLIFY AS IT PROGRESSES ACROSS THE MS RIVER VALLEY TONIGHT AND
THE TN VALLEY ON THURSDAY...WHILE A STRONG SHORTWAVE DROPS INTO ITS
BASE.

HIGH PRESSURE IS EXPECTED TO PERSIST OVER THE CAROLINAS AND GA
TONIGHT...WHILE WEAK MOIST ISENTROPIC UPGLIDE SETS UP IN THE LOW
LEVEL. LOW CLOUDS AND EVENTUALLY PRECIPITATION WILL SPREAD NORTH
ACROSS THE AREA...STARTING IN THE PIEDMONT...AND EXTENDING TO THE
MOUNTAINS BY DAYBREAK. WITH SOME LOW MINIMUM TEMPERATURES EXPECTED
IN MOUNTAIN VALLEYS TONIGHT...A FEW AREAS COULD SEE FREEZING RAIN
AROUND DAYBREAK...MAINLY IN THE SW MOUNTAINS. IF TEMPERATURES WARM
WITH INCREASING CLOUD COVER BEFORE DAWN AS GUIDANCE SUGGESTS...
FREEZING RAIN WOULD BE LESS LIKELY. ICE AMOUNTS WOULD BE QUITE LIGHT
AT BEST. WITH VERY LOW POPS AND LOW CONFIDENCE...NO FREEZING RAIN
ADVISORY WILL BE ISSUED AT THIS TIME.

ON THURSDAY A SURFACE LOW WILL MOVE NE FROM THE TN VALLEY TO THE
CENTRAL APPALACHIANS...WHILE ANOTHER DEVELOPS OVER THE GULF STREAM
AND MOVES NE OFF THE CAROLINA COAST. A COLD FRONT WILL APPROACH OUR
AREA FROM THE WEST ON THURSDAY MORNING...CROSSING THE AREA THURSDAY
AFTERNOON. POPS WILL RAMP UP AS THE FRONT REACHES THE AREA. RAPID
AND ROBUST COLD ADVECTION WILL SET UP IN THE WAKE OF THE FRONT...
RESULTING A FAST LOWERING OF SNOW LEVELS FROM THE HIGH PEAKS OF NC
IN THE MID AFTERNOON...TO THE VALLEY FLOORS BY EVENING. MOST SNOW
ACCUMULATIONS WILL REMAIN AT HIGHER ELEVATIONS...AND GENERALLY UNDER
ONE INCH.

MINIMUM TEMPERATURES TONIGHT WILL RUN AROUND 5 DEGREES ABOVE NORMAL
TONIGHT...WHILE MAXIMUM TEMPERATURES WILL RUN NEAR NORMAL ON
THURSDAY.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 255 PM EST WEDNESDAY...NW FLOW WILL INCREASE RAPIDLY ACROSS
THE NC MTNS THURSDAY EVENING. H8 WINDS INCREASE TO 40 TO 50 KTS
WHILE TEMPS PLUNGE TO -17 DEG C BY 12 UTC FRIDAY. LAPSE RATES WILL
BE STEEPEST DURING THE EVENING HOURS...BUT SNOW TO LIQUID RATIOS
SHOULD INCREASE TO 20 TO 1 LATE THURSDAY NIGHT. OVERALL WE BARELY
HIT 12 HOUR WINTER STORM CRITERIA OVER THE NRN MTNS AND ACROSS THE
HIGHER ELEVATIONS ALONG THE TN LINE OVER THE CENTRAL AND SW MTNS.
THEREFORE I WILL UPGRADE THE WINTER STORM WATCH TO A WARNING. THIS
WILL ALSO ALLOW ME TO ROLL THE THREAT OF HIGH WINDS AND LOW WIND
CHILL VALUES INTO THE WINTER STORM WARNING. ELEVATIONS ABOVE 3500
FEET SHOULD SEE TEMPS DROP TO 5 TO 7 ABOVE BY 12 UTC FRI. WITH THE
STRONG WINDS THIS PUTS THESE ELEVATIONS WELL INTO THE WIND CHILL
ADVISORY CRITERIA. ALL OF THIS COMBINED WILL MAKE FOR DANGEROUS
CONDITIONS OVER THE WARNING AREA...SO I/M NOT TOO CONCERNED EVEN IF
WE FALL A LITTLE BELOW WARNING CRITERIA ACCUMULATIONS.

FARTHER TO THE EAST...THE UPPER FRENCH BROAD VALLEY AND THE EAST
SLOPES OF THE NC BLUE RIDGE LOOK PRIMED FOR A HIGH WIND EVENT. SINCE
THESE ZONES WILL GET CONSIDERABLY LESS SNOWFALL...A HIGH WIND WATCH
WILL BE ISSUED FOR THESE LOCATIONS. I/M GOING WITH A WATCH AS THIS
IS A THIRD PERIOD EVENT AND I/D RATHER NOT PUT A WARNING OUT QUITE
THAT FAR.

HIGH TEMPERATURES ON FRIDAY WILL RUN AROUND 10 TO 15 DEGREES BELOW
NORMAL OVER THE FOOTHILLS AND PIEDMONT AND AROUND 20 DEGREES BELOW
NORMAL OVER THE MOUNTAINS. FAIR AND COLD CONDITIONS WILL CONTINUE
FROM FRIDAY NIGHT AND SATURDAY.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
AS OF 230 PM EST...THERE IS REASONABLE CONSENSUS THAT A DEEPENING
CENTRAL CONUS TROUGH WILL PUSH THE POLAR JET SWD INTO TX SAT NIGHT.
THE NUMERICAL MODELS THEN DIVERGE SOMEWHAT SUN INTO MON WITH THE EWD
MIGRATION OF THE ENERGY AND THE ASSOCIATED COLD AIR INFILTRATION.
THE ECMWF REMAINS MORE AMPLIFIED WITH THE FULL LATITUDE TROUGH AS IT
MIGRATES EWD SUNDAY...AND THIS IS BETTER SUPPORTED BY THE CMC AND
THE ENSEMBLES THAN IS THE GFS SOLUTION...SO IT WILL BE PREFERRED.
AHEAD OF THIS DIGGING UPSTREAM SYSTEM...LOW LEVEL SRLY UPGLIDE FLOW
SAT NIGHT INTO SUN WILL GRADUALLY RETURN ATLANTIC AND GULF MOISTURE
ACROSS THE REGION. THERE SHOULD BE ENOUGH OF A WARM NOSE ALOFT TO
ALLOW ANY SAT NIGHT AND EARLY SUNDAY PRECIP TO BE EITHER RAIN OR
FREEZING RAIN. THE OFFSHORE SFC HIGH PRES CENTER IS NOT IN A
FAVORABLE POSITION FOR ANYTHING MORE THAN TRANSIENT IN SITU CAD
EARLY SUNDAY...SO ANY PRECIP BEGINNING AS FREEZING RAIN SHOULD BE
ABLE TO CHANGE OVER TO RAIN FAIRLY QUICKLY BY LATE SUN MORNING. THE
LOW LEVEL SRLY JET WILL THEN INCREASE THROUGH THE DAY TO ALLOW
PRECIP CHANCES AND RAIN RATES TO INCREASE...ESPECIALLY IN THE SW
MTNS.

MEANWHILE...THE 500 MB VORTEX WILL DEEPEN OVER ONTARIO SUN NIGHT
THROUGH MON. THIS WILL DRIVE THE DEEP AND COLD TROUGH EWD...WITH THE
LEADING EDGE OF THE ARCTIC AIRMASS MOVING THROUGH STARTING SUN
NIGHT...AND WITH REINFORCING COLD AIR ARRIVING THROUGH TUE MORNING
AS THE TROUGH BOTTOMS OUT OVER THE SRN APPALACHIANS. A RAPID
CHANGEOVER FROM RAIN TO SNOW IS THUS EXPECTED SUN NIGHT/MON MORNING
WITH ANY LINGERING POST FRONTAL MOISTURE OR NW UPSLOPE FLOW INTO THE
WRN MTNS. A FEW SNOW SHOWERS COULD BREAK CONTAINMENT E OF THE BLUE
RIDGE EARLY MON AS WELL. IN ADDITION TO THE BRIEF ROUND OF NW FLOW
MOISTURE IN THE COLD AIR FOLLOWING FROPA LATE SUN NIGHT INTO
MON...ANOTHER SURGE OF MOISTURE COULD ARRIVE ON MON NIGHT JUST AS
850 MB TEMPS FALL TO BELOW MINUS 20 C ACROSS THE NC MOUNTAINS.
SNOW...WIND...OR WIND CHILL ADVISORIES COULD BE NEEDED FOR PARTS OF
THE PERIOD FROM EARLY MONDAY INTO TUE ACROSS THE HIGHER TERRAIN.

A COLD AND DRY ARCTIC AIRMASS WILL THEN SETTLE OVER THE AREA THROUGH
TUESDAY INTO WED...WITH MINS 10 TO 15 DEGREES BELOW CLIMO...AND
MAXES 10 TO 20 DEGREES BELOW CLIMO. A COLD WAVE OUTLOOK COULD BE
NEEDED.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...VFR UNDER HIGH LEVEL CIRRUS UNTIL LOW CLOUDS ARRIVE IN
SUFFICIENT QUANTITY TO FOR A LOW MVFR CIG AROUND DAYBREAK THURSDAY
IN LIGHT MOIST LOW LEVEL LIFT. THE BEST CHANCE OF RAIN WILL BE MID
TO LATE MORNING. GUIDANCE DOES NOT SUPPORT A VSBY RESTRICTION AT
THAT TIME. WINDS WILL REMAINS FORM THE S.

ELSEWHERE...VFR UNDER HIGH LEVEL CIRRUS INITIALLY. MOIST LOW LEVEL
LIFT WILL SUPPORT LOW INCREASING LOW LEVEL CLOUDS TONIGHT...WITH
MVFR CIGS BEFORE DAWN...EXCEPT AFTER DAWN AT KHKY...AND IFR AT KAND.
PRECIPITATION CHANCES WILL BE BETTER BY MID MORNING...THROUGH
RAINFALL RATES WILL BE TOO LOW FOR VSBY RESTRICTIONS IN NC. GUIDANCE
SUPPORTS MVFR VSBY RESTRICTIONS LATE THURSDAY MORNING DUE TO RAIN
AND FOG AT KGSP AND KGMU...WITH IFR AT KAND.

OUTLOOK...PRECIPITATION/RESTRICTIONS ARE EXPECTED ACROSS THE REGION
FOR MUCH OF THURSDAY...AS A COLD FRONT SWEEPS ACROSS THE AREA. RAPID
IMPROVEMENT IS EXPECTED OUTSIDE THE MTNS DURING THE AFTERNOON/
EVENING. VERY GUSTY NW WINDS WILL DEVELOP BEHIND A COLD FRONT THU
NIGHT/EARLY FRIDAY...ESP ACROSS THE MTNS. DRY HIGH PRESSURE WILL
RETURN ON FRIDAY AND LINGER INTO SATURDAY. MOISTURE RETURNING AHEAD
OF ANOTHER COLD FRONT MAY PRODUCE RESTRICTIONS AND LIGHT PRECIP BY
EARLY SUNDAY.

CONFIDENCE TABLE...

            20-02Z        02-08Z        08-14Z        14-20Z
KCLT       HIGH 100%     HIGH 100%     HIGH  93%     MED   78%
KGSP       HIGH 100%     HIGH 100%     HIGH  83%     HIGH  92%
KAVL       HIGH 100%     HIGH 100%     HIGH  94%     MED   69%
KHKY       HIGH 100%     HIGH 100%     HIGH 100%     HIGH  82%
KGMU       HIGH 100%     HIGH 100%     HIGH  86%     HIGH  85%
KAND       HIGH 100%     HIGH  95%     MED   74%     HIGH  82%

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...HIGH WIND WATCH FROM THURSDAY EVENING THROUGH FRIDAY MORNING
     FOR NCZ053-065-501-503-505-507-509.
     WINTER STORM WARNING FROM 4 PM THURSDAY TO 7 AM EST FRIDAY FOR
     NCZ033-048>052-058.
     WINTER WEATHER ADVISORY FROM 4 PM THURSDAY TO 7 AM EST FRIDAY
     FOR NCZ048-051-052-058.
SC...NONE.

&&

SYNOPSIS...SBK
NEAR TERM...JAT
SHORT TERM...MCAVOY
LONG TERM...HG
AVIATION...JAT

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
425 AM EST WED JAN 1 2014

NCZ033-048>052-058-020930-
AVERY-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-GRAHAM-
425 AM EST WED JAN 1 2014

...WINTER STORM WATCH IN EFFECT FROM THURSDAY AFTERNOON THROUGH
FRIDAY MORNING ABOVE 3500 FEET...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN NORTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT.

HAZARDOUS WEATHER IS NOT EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

..THURSDAY...HEAVY SNOW POSSIBLE. A WINTER STORM WATCH HAS BEEN
ISSUED FOR THE TENNESSEE BORDER COUNTIES. IN ADDITION TO THE
SNOW...WIND CHILL VALUES OF 5 TO 10 BELOW ZERO WILL BE FELT AT
THE HIGHER MOUNTAIN ELEVATIONS.
..FRIDAY...HEAVY SNOW POSSIBLE. SNOW SHOWERS SHOULD COME TO AN END
FRIDAY MORNING.
..SATURDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SUNDAY...SNOW POSSIBLE. AN ARCTIC COLD FRONT WILL CROSS THE
SOUTHEAST STATES LATE IN THE WEEKEND. THERE IS A GREAT DEAL OF
UNCERTAINTY AS TO HOW MUCH MOISTURE WILL ACCOMPANY THE FRONT.
HOWEVER...ACCUMULATING SNOWFALL WILL BE POSSIBLE OVER THE NORTH
CAROLINA MOUNTAINS.
..MONDAY...SNOW POSSIBLE. THERE WILL BE A CONTINUED CHANCE OF SNOW
ACROSS THE NORTH CAROLINA MOUNTAINS ON MONDAY. VERY COLD
TEMPERATURES ARE ALSO EXPECTED.
..TUESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

NCZ053-059-062-501-503-505-020930-
BUNCOMBE-NORTHERN JACKSON-MACON-CALDWELL MOUNTAINS-BURKE MOUNTAINS-
MCDOWELL MOUNTAINS-
425 AM EST WED JAN 1 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN NORTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT.

HAZARDOUS WEATHER IS NOT EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

..THURSDAY...LIGHT SNOW POSSIBLE. AS LOW PRESSURE MOVES NEAR THE
AREA THURSDAY NIGHT...A PERIOD OF SNOW WILL DEVELOP ACROSS THE
NORTH CAROLINA MOUNTAINS. ALTHOUGH HEAVY SNOW ACCUMULATIONS SHOULD
BE LIMITED TO THE HIGH ELEVATIONS NEAR THE TENNESSEE BORDER...
LIGHT ACCUMULATIONS WILL ALSO BE POSSIBLE FARTHER EAST INTO THE
MOUNTAINS. STRONG NORTHWEST WINDS WILL ALSO DEVELOP THURSDAY
EVENING...AND MAY GUST AS HIGH AS 50 MPH ACROSS THE HIGH
ELEVATIONS...AND ACROSS THE EASTERN ESCARPMENT OF THE BLUE RIDGE.
WIND CHILL VALUES OF 5 TO 10 BELOW ZERO WILL BE FELT AT THE HIGHER
MOUNTAIN ELEVATIONS.
..FRIDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SATURDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SUNDAY...SNOW POSSIBLE. AN ARCTIC COLD FRONT WILL CROSS THE
SOUTHEAST STATES LATE IN THE WEEKEND. THERE IS A GREAT DEAL OF
UNCERTAINTY AS TO HOW MUCH MOISTURE WILL ACCOMPANY THE FRONT.
HOWEVER...ACCUMULATING SNOWFALL WILL BE POSSIBLE OVER THE NORTH
CAROLINA MOUNTAINS.
..MONDAY...SNOW POSSIBLE. THERE WILL BE A CONTINUED CHANCE OF SNOW
ACROSS THE NORTH CAROLINA MOUNTAINS ON MONDAY. VERY COLD
TEMPERATURES ARE ALSO EXPECTED.
..TUESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

GAZ010-017-018-026-028-029-NCZ035>037-056-057-063>065-068>072-082-
502-504-506>510-SCZ001>014-019-020930-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-ALEXANDER-IREDELL-
DAVIE-CATAWBA-ROWAN-SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-
CLEVELAND-LINCOLN-GASTON-MECKLENBURG-CABARRUS-UNION NC-
GREATER CALDWELL-GREATER BURKE-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-
425 AM EST WED JAN 1 2014

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

.DAY ONE...TODAY AND TONIGHT.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

..THURSDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..FRIDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SATURDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SUNDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..MONDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..TUESDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

LANE