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000
FXUS62 KGSP 152339
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
739 PM EDT SAT JUN 15 2013

.SYNOPSIS...
DRY HIGH PRESSURE OVER THE CAROLINAS WILL DRIFT OFF THE CAROLINA
COAST THROUGH SUNDAY AS THE NEXT COLD FRONT CROSSES THE UPPER
MISSISSIPPI AND OHIO VALLEYS. EXPECT THIS FRONT TO BRING GOOD
COVERAGE OF RAINFALL IN THE EARLY HALF OF THE WEEK. THE FRONT WILL
THEN STALL FROM WEST TO EAST JUST SOUTH OF OUR REGION AND SLOWLY
DISSIPATE LATE IN THE WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
AS OF 735 PM...CU BEGINNING TO DISSIPATE OUTSIDE OF THE MTNS...BUT
WILL LINGER A LITTLE LONGER OVER THE MTNS BEFORE DISSIPATING.
OTHERWISE...EXPECT CIRRUS TO MOVE OVERHEAD THE REST OF THE NIGHT.
STILL EXPECT VALLEY FOG OVER THE SWRN NC MTNS. WINDS WILL DIMINISH
THRU THE EVENING AS WELL. GOING FCST HAS THIS WELL IN HAND...SO
UPDATES MAINLY FOR CURRENT CONDITIONS.

AS OF 225 PM EDT SATURDAY...QUITE A BIT OF CU HAVE SPROUTED UP OVER
THE REGION THIS AFTERNOON...ESPECIALLY ACROSS THE MOUNTAINS.
INTERESTINGLY...DOWNSLOPE HAS KEPT THE WESTERN NC FOOTHILLS NEARLY
CLOUD FREE THIS AFTERNOON. THE LOWER CLOUDS SHOULD DISSIPATE AROUND
SUNSET...THOUGH SOME BLOWOFF FROM UPSTREAM CONVECTION WILL BRING
THIN CIRRUS ACROSS THE SRN APPS AT TIMES OVERNIGHT. A LITTLE VALLEY
FOG IS POSSIBLE OVER THE SOUTHWEST NC MTNS TONIGHT IN THE FAVORED
AREAS.

THE FLOW WILL FLATTEN OUT TOMORROW AS TROUGHING REASSERTS ITSELF
OVER THE ERN CONUS. THE AIRMASS WILL REMAIN CAPPED AND RATHER DRY
MOST OF THE DAY OVER THE PIEDMONT AND FOOTHILLS...BUT LAYER RH/S AND
SFC DEWPOINTS WILL INCREASE OVER THE MTNS TO THE POINT THAT SCT
SHOWERS AND TSTMS SHOULD DEVELOP DURING THE AFTN HOURS. BY LATE AFTN
AND EARLY EVENING AN APPROACHING SHORT WAVE MAY CAUSE THE CONVECTION
TO INCREASE IN COVERAGE AND GRADUALLY SPREAD EAST OF THE MOUNTAINS
IN OPPOSITION TO A TYPICAL DIURNAL CONVECTIVE TREND.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
AT 230 PM EDT SATURDAY...AN UPPER TROUGH WILL AMPLIFY OVER THE
EASTERN HALF OF THE NATION FROM SUNDAY NIGHT INTO TUESDAY. ON
SIGNIFICANT SHORTWAVE WILL CROSS OUR AREA ON SUNDAY NIGHT...AND
ANOTHER ON TUESDAY. A BAND OF MOISTURE ASSOCIATED WITH A THE
REMAINS OF AN OLD FRONT WILL SETTLE SOUTH OVER OUR AREA ON SUNDAY
NIGHT...INTERACTING WITH A GENTLE SOUTHERLY FLOW ON THE BACK SIDE OF
ATLANTIC HIGH PRESSURE. THE RESULT WILL BE GREATER THAN NORMAL
PRECIPITATION CHANCES THAT INCREASE WITH TIME. A COLD FRONT
APPROACHES FROM THE WEST ON TUESDAY..LENDING ADDITIONAL SUPPORT OF
PRECIPITATION. DEEP MOISTURE WILL BECOME MORE SUPPORTIVE OF HEAVIER
RAINFALL WITH TIME. MODEL SOUNDINGS GENERALLY LIMIT CAPE TO LESS
THEN 1000 J/KG...BUT SHOW GRADUALLY INCREASING LOW LEVEL SHEAR.
TEMPERATURES WILL EXPERIENCE A DECREASING DIURNAL TREND AS MOISTURE
INCREASES...WITH MAXIMUMS FALLING AND MINIMUMS RISING.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 224 PM SATURDAY...THE MEDIUM RANGE BEGINS WITH TUESDAY
EVENING. A SLOW MOVING WEAK COLD FRONT WILL MOVE EAST AND SOUTHEAST
OF OUR AREA TUESDAY NIGHT. WAVES OF LOW PRESSURE ALONG THE FRONT
WILL BRING AREAS OF SHOWERS AND A FEW STORMS MAINLY TO THE PIEDMONT
AS THE FRONT MOVES AWAY. CAPE VALUES WILL BE RATHER LOW AND
THEREFORE LITTLE STIMULUS FOR STORMS. DRIER AIR MOST SO THE MORE
NORTH YOU GO TOWARD THE CENTER OF THE TRANSIENT HIGH PRESSURE
PASSING FROM THE GREAT LAKES AND ACROSS PA THEN OFF THE JERSEY COAST
ON THURSDAY. STALLED OUT FRONT WILL LINGER FROM THE GULF STATES TO
THE CAROLINA COAST LAST HALF OF THE WEEK AS IT SLOWLY DISSIPATES.
EXPECT WIDELY SCATTERED TO SCATTERED LATE DAY SHOWERS AND A FEW
STORMS WITH DIFFERENTIAL HEATING AROUND THE MOUNTAINS PROVIDING SOME
AFTERNOON DEVELOPMENT. CAPE VALUES CONTINUE TO BE ON THE LOW SIDE
WITH ONLY A FEW HUNDRED IN CAPE VALUES ACCORDING TO THE GFS. THE
CENTER OF THE UPPER RIDGE WILL BE BUILDING INTO OUR REGION FROM THE
WEST AT THE END OF THE WEEK HELPING TO INCREASE TEMPERATURES A BIT.
HIGHS WILL BE A BIT BELOW NORMAL FROM WEDNESDAY TO FRIDAY AND CLOSER
TO NORMAL NEXT WEEKEND.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...THE FEW TO SCT CU WILL DISSIPATE WITH LOSS
OF HEATING THIS EVENING. CIRRUS WILL INCREASE OVERNIGHT AS WEAK
SHORT WAVES MOVE OVER THE AREA. EXPECT PATCHY VALLEY FOG AND SOME
LOW STRATUS TO DEVELOP OVER THE SOUTHWEST AND CENTRAL MTNS. THE
FRENCH BROAD VALLEY HAS HAD ANOTHER DAY TO DRY OUT...SO I DON/T SEE
WIDESPREAD RESTRICTIVE CIGS OR VSBYS...BUT A FEW HOURS OF MVFR
FOG...AND POSSIBLY A BRIEF FOG BANK...WILL AFFECT THE KAVL AIRFIELD
OVERNIGHT. EXPECT SCT CU TO RETURN DURING THE AFTERNOON AND
EVENTUALLY BECOME BKN OVER THE MTNS. MTNS HAVE THE BEST CHC OF
SEEING ANY CONVECTION...BUT CHC LOW ENUF AND TIMING UNCERTAIN ENUF
TO LEAVE OUT OF KAVL TAF FOR NOW. S TO SW WIND WILL DIMINISH
OVERNIGHT AND RETURN WITH MIXING BY MID MORNING SUNDAY. SW WINDS
CONTINUE THRU THE AFTERNOON.

OUTLOOK...THE CHANCES FOR SHRA/TSTMS AND ASSOCIATED FLIGHT
RESTRICTIONS WILL INCREASE MON THROUGH TUE WITH THE ARRIVAL OF A
FRONT AND LINGER THROUGH AT LEAST MID WEEK.

CONFIDENCE TABLE...

            23-05Z        05-11Z        11-17Z        17-23Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH 100%     HIGH 100%     HIGH  97%     HIGH 100%
KHKY       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGMU       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAND       HIGH 100%     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...DEO
NEAR TERM...MCAVOY/RWH
SHORT TERM...JAT
LONG TERM...DEO
AVIATION...RWH