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000
FXUS62 KGSP 191150
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
750 AM EDT WED JUN 19 2013

.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION FROM THE NORTHWEST
TODAY...WITH A WEAK SURFACE COLD FRONT THEN SETTLING SOUTHWARD ALONG
THE APPALACHIAN MOUNTAIN CHAIN INTO THURSDAY. HIGH PRESSURE WILL
BUILD OVER THE AREA FROM FRIDAY ONWARD...WITH INCREASINGLY WARM AND
HUMID CONDITIONS DEVELOPING INTO EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 0745 AM EDT WEDNESDAY...SOME SHOWERS HAVE DEVELOPED OVER THE
SC UPSTATE IN RESPONSE TO AN UPPER IMPULSE MOVING THROUGH THE AREA.
HENCE...HAVE MADE A QUICK UPDTATE TO INCLUDE SOME SCT SHOWERS TO THE
FORECAST FOR MAINLY JUST THE MORNING HOURS OUTSIDE OF THE MOUNTAINS.
STILL EXPECT SCT AFTERNOON CONVECTION OVER THE MOUNTAINS.

PREVIOUS DISCUSSION:
A FAIRLY CONSISTENT DECK OF LOW CLOUDS REMAINS ACROSS REGION THIS
MORNING...BUT SHOULD BEGIN TO ERODE AFTER SUNRISE ACROSS THE HIGHER
TERRAIN AND THE NC PIEDMONT.  OTHER LOCATIONS SUCH AS NORTHEAST
GEORGIA AND THE UPSTATE OF SC WILL SEE CLOUDS LINGER FOR A FEW
HOURS...BEFORE FINALLY LIFTING OUT BY LATE MORNING.  CURRENT
FORECAST REMAINS ON TRACK AND NO CHANGES WERE MADE.

PREVIOUS DISCUSSION...

AS OF 230 AM EDT WEDNESDAY...CONDITIONS WILL CONTINUE TO IMPROVE
ACROSS NORTHEAST GEORGIA AND THE CAROLINAS OVER THE NEXT 24 HOURS AS
UPPER LEVEL CYCLONIC FLOW SHIFTS EAST ALLOWING FOR BUILDING SURFACE
HIGH PRESSURE.  COLD FRONT THAT MOVED THROUGH THE REGION TUESDAY
THAT SPAWNED NUMEROUS SHOWERS AND THUNDERSTORMS HAS PUSHED INTO THE
MIDLANDS/LOW COUNTRY OF SC.  BEHIND THE FRONT...MUCH DRIER AIR CAN
BE SEEN ON THE SFC ANALYSIS AS MOST SITES ACROSS NC ARE REPORTING
DEW POINTS IN THE UPPER 50S TO LOWER 60S.  THIS DRIER AIRMASS WILL
CONTINUE ADVECTING SOUTHWARD ALLOWING FOR A FAIRLY NICE DAY ACROSS
THE REGION WITH THE ONLY EXCEPTION BEING SOME MECHANICALLY FORCED
CONVECTION IN THE HIGHER TERRAIN DURING THE AFTERNOON HOURS.  HIGH
TEMPERATURES ON WEDNESDAY WILL BE SLIGHTLY BELOW NORMAL AS MID 80S
ARE EXPECTED ACROSS THE PIEDMONT...AND UPPER 70S TO LOWER 80S
ELSEWHERE.  TOWARDS THE END OF THE NEAR TERM PERIOD...THE RIDGE
SLIDES FURTHER TO THE NORTHEAST ALLOWING FOR A RETURN TO EASTERLY
FLOW PROMPTING SOME INCREASES IN BOUNDARY LAYER MOISTURE WHICH WILL
LEAD TO INCREASING CLOUDINESS FOR THURSDAY MORNING.  LOWS ON
THURSDAY MORNING WILL BE SLIGHTLY BELOW NORMAL.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 230 AM EDT WED...SFC HIGH PRES WILL STRETCH FROM THE MID
ATLANTIC COAST THROUGH THE WESTERN CAROLINAS ON THU. THIS WILL
PRODUCE SOME EASTERLY FLOW IN THE BOUNDARY LAYER OVER THE
AREA...CONTRIBUTE A VERY LIGHT UPSLOPE...AND HALT ANY BRIEF NEAR
SURFACE DRYING. THE COMBINATION OF LIGHT UPSLOPE...WIND FIELD
CONVERGENCE IN THE SOUTHWEST MTNS...AND CONDITIONAL INSTABILITY IN
THE PROFILES WILL LIKELY PRODUCE SCATTERED CONVECTIONS OVER THE MTNS
AND ISOLD COVERAGE IN THE ADJACENT FOOTHILLS DURING THE DIURNALLY
FAVORED AFTN AND EVENING PERIODS. WILL CONTINUE TO FEATURE MAX TEMPS
ABOUT A CATEGORY BELOW CLIMATOLOGY.

UPPER LEVEL HEIGHTS WILL START TO RISE IN EARNEST FROM THE WEST ON
FRIDAY. THE SW NC MTNS APPEAR TO HAVE THE BEST CHANCE OF ANY ISOLD
TO SCT CONVECTION AGAIN ON FRI AFTN IN THE BEST LOW LEVEL
CONVERGENCE...HOWEVER...POPS WILL BE LESS THAN THU SINCE PROFILES
ARE A BIT DRIER. MAX TEMPS MAY RECOVER 1 TO 2 DEGREES IN MOST
LOCATIONS...BUT REMAIN QUITE COMPARABLE TO WED VALUES.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 240 AM EDT WED...A 591 DM H5 RIDGE WILL REMAIN DOMINANT OVER
THE SE THROUGH THE MEDIUM RANGE PERIOD. ANTICIPATE A MAINLY DIURNAL
TREND OF ISOLD TO SCATTERED AFTERNOON POPS THROUGH THE PERIOD...WITH
THE MTNS BEING THE PRIMARY FOCUS. THE GFS IS THE MOST AGGRESSIVE IN
BRINGING AN INVERTED COASTAL TROUGH BACK INLAND ALONG THE SAVANNAH
ON SATURDAY...BUT THE OTHER OPERATIONAL AND ENSEMBLE MEAN SOLUTIONS
KEEP THE SYSTEM ALONG THE IMMEDIATE COAST WITH THE RIDGE PERSISTING
OVER THE WRN CAROLINAS. THE DIURNAL PATTERN OF ISOLD TO SCT SHOWERS
AND THUNDERSTORMS SHOULD THUS CONTINUE SAT THROUGH TUE...WITH
TEMPERATURES STEADILY WARMING UNDER THE UPPER RIDGE. EXPECT MAXES TO
REACH CLIMATE NORMALS BY SUNDAY AND THEN EXCEED THEM MON AND TUE.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...CIGS HAVE LIFTED ACROSS THE PIEDMONT OF NORTH CAROLINA
THUS ALLOWING FOR A VFR FORECAST THROUGH THE PERIOD. HOWEVER...SOME
SHRA HAVE DEVELOPED OVER THE SC UPSTATE IN RESPONSE TO AN UPPER
LEVEL IMPULSE PASSING THROUGH. THESE ARE MOVING EASTWARD AND HAVE
INCLUDED A VCSH AROUND MIDDAY WITH LOWERING VFR CIG. COULD BE A
BRIEF VSBY RESTRICTION BUT CONFIDENCE TOO LOW FOR NOW TO INCLUDE
IN TAF. DRIER AIR ADVECTS IN FROM THE NORTH LATER TODAY AS AND
HIGH PRESSURE RIDGES INTO THE REGION. EXPECTING NOTHING MORE THAN
A FEW SCT MID CLOUDS AND HIGH LEVEL CIGS TONIGHT. WINDS WILL BE
LIGHT NE THROUGH MOST OF THE PERIOD BEFORE SHIFTING TO AN EASTERLY
COMPONENT TOWARDS THE END OF THE FORECAST CYCLE.

ELSEWHERE...SHRA OVER THE SC UPSTATE LWERING VSBYS TO MVFR AT GSP
AND GMU. CONDITIONS SHOULD CONTINUE IMPROVE BY LATE MORNING AS SRRA
MOVE EAST. NOT EXPECTING ANY PRECIPITATION AT ANY OF THE SC SITES
THIS AFTERNOON AS HIGH PRESSURE BEGINS TO DOMINATE AND CAPPING
INVERSION HOLDS.  HOWEVER...FOR THE NC SITES...WENT WITH PROB30 AT
KAVL AS SHORT TERM CONVECTION ALLOWING GUIDANCE INDICATES SOME
UPDRAFTS BEING ABLE TO OVERCOME THE CAP WITH THE AID OF MECHANICAL
FORCING.  BEYOND THAT...LATEST GUIDANCE INDICATES A LOWERING OF CIGS
TO HIGH END MVFR ACROSS MOST SITES THIS EVENING AS BOUNDARY LAYER
MOISTURE INCREASES. WINDS WILL BE LIGHT AND NORTHERLY THROUGH MOST
OF THE PERIOD BEFORE SHIFTING TO AN EASTERLY COMPONENT TOWARDS THE
END OF THE FORECAST CYCLE.

OUTLOOK...INCREASING MOISTURE TOWARDS THE END OF THE WORK WEEK WILL
ALLOW SOME DIURNAL CONVECTION TO DEVELOP EACH AFTERNOON.
OTHERWISE...MOST AREAS SHOULD SEE DRY CONDITIONS.  SOME EARLY
MORNING STRATUS WILL ALSO BE POSSIBLE ON THURSDAY AND FRIDAY PERHAPS
CAUSING SOME RESTRICTIONS.

CONFIDENCE TABLE...

            11-17Z        17-23Z        23-05Z        05-11Z
KCLT       HIGH  95%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH  90%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH  90%     HIGH 100%     HIGH 100%     HIGH  95%
KHKY       HIGH  90%     HIGH 100%     HIGH 100%     HIGH  90%
KGMU       HIGH  90%     HIGH 100%     HIGH 100%     HIGH 100%
KAND       HIGH  90%     HIGH 100%     HIGH 100%     HIGH 100%

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...CDG/LG
SHORT TERM...HG
LONG TERM...HG
AVIATION...CDG