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000
FXUS62 KGSP 251850
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
250 PM EDT SAT MAY 25 2013

.SYNOPSIS...
HIGH PRESSURE OVER THE SOUTHEAST WILL BRING COOLER THAN NORMAL
TEMPERATURES FOR THIS WEEKEND. EARLY NEXT WEEK THE HIGH WILL DRIFT
EAST OFF THE CAROLINA COAST RESULTING IN A CHANCE OF AFTERNOON
SHOWERS AND THUNDERSTORMS...MAINLY OVER THE MOUNTAINS. A RATHER
STRONG UPPER RIDGE WILL BRING VERY WARM TEMPERATURES FOR THE SECOND
HALF OF THE WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
FOR THE REST OF THE AFTERNOON...STILL LOOKS LIKE A SPECTACULAR
SPRING DAY...WITH COOL TEMPS...SUNNY SKY...AND LIGHT WIND. SOME
PATCHES OF MID LEVEL CLOUDS WILL SPILL OVER THE MTNS AND ACROSS THE
NC PIEDMONT THROUGH LATE AFTERNOON...OTHERWISE IT SHOULD REMAIN
FAIR. GET OUT AND ENJOY IT WHILE YOU CAN BECAUSE YOU WILL WISH FOR A
DAY LIKE THIS A MONTH OR TWO FROM NOW.

FOR TONIGHT AND SUNDAY...THE UPPER PATTERN REMAINS INTACT WITH A
DEEP NW FLOW OVER THE APPALACHIANS AND WESTERN CAROLINAS BROUGHT
ABOUT BY AN UPPER RIDGE AXIS OVER THE PLAINS AND AN UPPER LOW MOVING
ALONG THE NEW ENGLAND COAST. THIS WILL KEEP HIGH PRESSURE RIDGING
DOWN FROM THE NORTH FOR THE NEXT 24 HOURS. AN INTERESTING WRINKLE
HAS DEVELOPED WITH MCS REMNANTS FCST BY THE NAM AND GFS DROPPING
DOWN OVER THE REGION IN THE NW FLOW LATE TONIGHT AND EARLY SUNDAY.
IT SEEMS REASONABLE THAT A LARGE AREA OF MID AND HIGH LEVEL
CONVECTIVE DEBRIS WILL GIVE US A PERIOD OF MOSTLY CLOUDY SKY SUNDAY
MORNING GIVEN SATELLITE TRENDS. HAVE BUMPED UP MIN TEMPS TONIGHT A
DEGREE OR TWO ACCORDINGLY. THE GFS EVEN ALLOWS FOR SOME SPRINKLES.
HAVE KEPT THE FCST DRY BECAUSE EVEN IF SPRINKLES HAPPEN WE PROBABLY
WOULD NOT MEASURE. THE CLOUDS SHOULD THIN ON SUNDAY AND STILL ALLOW
FOR SOME DECENT SUN. HIGH TEMPS WILL BE A FEW DEGREES WARMER THAN
TODAY BUT STILL A CATEGORY OR SO BELOW NORMAL.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
AS OF 205 PM SATURDAY...AS THE UPPER TROUGH DEPARTS TO THE EAST FROM
THE ATLANTIC COAST SUNDAY NIGHT INTO MONDAY...THE WIND WILL SHIFT
AROUND TO THE SOUTHWEST WITH THE WARM FRONTAL PASSAGE EARLY MONDAY.
EXPECT DRY CONDITIONS SUNDAY NIGHT ALTHOUGH THE MOUNTAINS COULD GET
A SPRINKLE WITH HIGHER MOISTURE.

THE NAM IS QUITE DRY COMPARED TO THE OTHER MODELS TO START THE WEEK.
THE NAM GENERATES SOME MONDAY AFTERNOON CONVECTION OVER THE TRIAD
AND TRIANGLE OF NC BY 00Z TUESDAY. THE GFS AND SREF HAVE CONVECTION
ALL OVER THE WESTERN CAROLINAS AND NE GA LATE MONDAY WITH MOST
FAVORED IN WESTERN NC. THE GFS HAS 500 TO 1000 CAPE OVER THE AREA
LATE MONDAY WITH THE CAPE MAX PROGRESSING FROM ASHEVILLE TO
SPARTANBURG AND GAFFNEY. GOT SLIGHT CHANCE POP NON-MOUNTAINS AND LOW
CHANCE MTNS LATE MONDAY. LOW LEVEL FLOW BECOMES MORE CONSISTENTLY
SOUTH TO SOUTHWEST BY LATE MONDAY AND BY LATE TUESDAY ALL FLOW
ACROSS OUR REGION WILL BE SOUTHERLY. BEST CAPES LATE TUESDAY WILL BE
OVER CAROLINA PIEDMONT. GFS HAS 1000 TO 1200 CAPE VALUES OVER CLT
AND MONROE LATE TUESDAY. SHOULD SEE ABOUT THE SAME COVERAGE LATE
TUESDAY AS LATE MONDAY FAVORING NC. TEMPERATURES WILL BE NEAR NORMAL
MONDAY AND ABOUT A CATEGORY ABOVE NORMAL TUESDAY FOR HIGHS AS UPPER
RIDGING BUILDS FROM THE WEST.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 230 PM EDT SATURDAY...A LONG WAVE RIDGE WILL CONTROL THE
WEATHER OVER THE REGION FROM MID WEEK TO NEXT WEEKEND. CAPE VALUES
GENERALLY LESS THAN 1000 LATE WEDNESDAY AND STABLE FOR THE REST OF
THE WEEK. SHEAR WILL BE WEAK MID WEEK FOR THE SECOND HALF OF THE
WEEK. GOING FOR SLIGHT MTN POPS LATE WEDNESDAY AND THURSDAY WITH THE
ONLY TRIGGER BEING DIFFERENTIAL HEATING. NO POP FRIDAY AND SATURDAY.
UPPER RIDGE STILL PROJECTED TO BE STRONGEST THURSDAY AND FRIDAY THEN
STARTING TO BREAK DOWN SATURDAY WITH UPPER TROUGH COMING ACROSS
UPPER PLAINS. TEMPERATURES A FEW DEGREES ABOVE NORMAL BUT SOME
AFFECTS OF STABLE AIR OFF ATLANTIC AROUND SOUTH SIDE OF RIDGE
PERHAPS CREATING THE COOLER THAN PREVIOUSLY PROJECTED NEAR 90 DEGREE
WEATHER.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...VFR THROUGH THE PERIOD...COURTESY OF HIGH
PRESSURE RIDGING DOWN FROM THE GREAT LAKES. WIND WILL BE WSW OR SW
OVER MUCH OF THE PIEDMONT BECAUSE OF A LEE TROF...BUT WILL COME BACK
AROUND TO VERY LIGHT FROM THE N...OR VARIABLE...WITH SUNSET. WHEN
THE WIND COMES UP SUNDAY...IT SHOULD REMAIN N AT LEAST FOR MOST OF
THE MORNING. THE MODELS HAVE LATCHED ONTO THE MCS OVER ILLINOIS AND
ARE IN LOCK STEP WITH BRINGING MID AND HIGH LEVEL DEBRIS CLOUDS DOWN
ACROSS THE WESTERN CAROLINAS LATE TONIGHT AND SUNDAY MORNING. THE
GFS EVEN ALLOWS FOR SOME SPRINKLES. THUS...A MID LEVEL CEILING WAS
GRADUALLY INTRODUCED FROM THE NW THROUGH LATE TONIGHT. THE CEILING
SHOULD THIN BY LATE MORNING SUNDAY..

OUTLOOK...WITH DRY HIGH PRES DOMINATING THE WEATHER ACRS THE REGION
THRU MONDAY MORNING...NO SIGNIFICANT AVIATION CONCERNS ARE
EXPECTED. A RETURN TO DIURNAL THUNDERSTORMS IS EXPECTED FOR MONDAY
AND TUESDAY WITH ASSOCIATED RESTRICTIONS IN THE VICINITY OF STORMS.
THE SHOWER CHANCE DIMINISHES WEDNESDAY AND THURSDAY AS AN UPPER HIGH
WILL SUPPRESS DEEP CONVECTION.

CONFIDENCE TABLE...

            19-01Z        01-07Z        07-13Z        13-19Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH 100%     HIGH 100%     HIGH 100%     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

&&

.FIRE WEATHER...
THE 10-HOUR FUELS HAVE DRIED OUT ENOUGH TO REACH CRITICAL LEVELS
ACRS MUCH OF NE GA TODAY. ANOTHER DRY DAY IS ON TAP...WITH A FEW
HOURS OF RH VALUES DIPPING BELOW 25 PERCENT THIS AFTN.
FORTUNATELY...WINDS WILL BE MUCH LIGHTER THAN YESTERDAY.
HOWEVER...THE COMBINATION OF DRY FUELS AND LOW RH WARRANTS A FIRE
DANGER STATEMENT SOUTH OF THE RIDGE IN RABUN COUNTY. THIS ALSO LINES
UP WITH THE FFC OFFICE.

&&

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

&&

$$
SYNOPSIS...PAT
NEAR TERM...PM
SHORT TERM...DEO
LONG TERM...DEO
AVIATION...PM
FIRE WEATHER...