000
FXUS62 KGSP 251114
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
714 AM EDT SAT MAY 25 2013

.SYNOPSIS...
AN UPPER LEVEL TROUGH WILL MOVE OFF THE ATLANTIC COAST TODAY WHILE
SURFACE HIGH PRESSURE CONTINUES THE COOLER THAN NORMAL TEMPERATURES
THIS WEEKEND. EXPECT AFTERNOON SHOWERS AND THUNDERSTORMS EARLY NEXT
WEEK...MAINLY OVER THE MOUNTAINS. A RATHER STRONG UPPER RIDGE WILL
BRING VERY WARM TEMPERATURES FOR THE SECOND HALF OF THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 500 AM...A QUICK UPDATE WAS MADE TO THE SKY GRIDS AND
TEMP/DEWPTS TO MATCH LATEST OBS AND SAT IMAGERY.

AS OF 200 AM...QUIET WEATHER ON TAP FOR THE NEAR TERM...AS HIGH PRES
CONTINUES TO BUILD IN FROM THE NW UNDER CONFLUENT NWLY FLOW ALOFT.
THICKNESSES BEING TO REBOUND...BUT A COLD START TO THE DAY (MIN
TEMPS NEAR RECORDS (SEE CLIMATE SECTION BELOW)) WILL KEEP TEMPS
MAINLY IN THE 70S BELOW 3500 FT...UNDER SUNNY SKIES.

TONIGHT...MODELS IN AGREEMENT ON MID-UPR LVL MOISTURE ROUNDING A
RIDGE AXIS TO OUR WEST AND STREAMING INTO THE AREA OVERNIGHT. THE
INCREASING CLOUDINESS AND REBOUNDING LLVL THICKNESSES SHUD RESULT IN
TEMPS NOT AS COLD AS THIS MORNING (MAINLY 40S MTNS AND UPR 40S TO
LWR 50S PIEDMONT).

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 305 AM SATURDAY...MID AND HIGH LEVEL CLOUDS WILL PERSIST OVER
THE REGION SUNDAY...ESPECIALLY IN THE MORNING HOURS. A SPRINKLE OR
LIGHT SHOWER IS POSSIBLE OVER THE MOUNTAINS. WHILE THE REGION WILL
REMAIN UNDER NW FLOW LATER IN THE DAY...MODEL TIME SECTIONS SHOW
DECREASING MOISTURE AND IT SHOULD BE A NICE AFTERNOON WITH MAX
TEMPERATURES RUNNING A FEW DEGREES BELOW NORMAL AND LOW HUMIDITY.

ONE MONDAY A WEAK WARM FRONT WILL CROSS THE REGION FROM THE
SOUTHWEST. THE GFS HAS THE BEST MOISTURE POOLING WITH THIS FEATURE
DOWN ALONG THE UPPER SAVANNAH RIVER VALLEY AND OVER THE CENTRAL AND
SOUTHWEST NC MTNS. THE NAM HAS IT MORE UP ACROSS THE WRN NC
PIEDMONT. THE SREF PROBABILITY OF 500 J/KG OF CAPE FAVORS AREAS
ACROSS THE UPSTATE AND SRN NC PIEDMONT. OVERALL...I THINK OUR
CURRENT AREA OF CHANCE POPS MAY BE A LITTLE TOO FAR TO THE
NORTH...THOUGH I DON/T SEE ANY REASON TO ADJUST IT FARTHER TO THE
SOUTH WITH THIS PACKAGE. WITH THE RIDGE BEGINNING TO BUILD IN DURING
THE AFTERNOON AND THE MODEST INSTABILITY...EVEN THE AREAS WITH THE
BEST CHANCE OF RAIN SHOULDN/T SEE MORE THAN A 30 TO 40 PERCENT
COVERAGE OF CONVECTION.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 210 AM EDT SATURDAY...A LONG WAVE RIDGE WILL CONTROL THE
WEATHER OVER THE REGION FROM TUESDAY ONWARD. THE MODELS...BOTH
SOUNDINGS AND PLAN VIEWS...INDICATE THAT THERE WILL BE ENOUGH LLVL
MOISTURE FOR CONVECTION TO FIRE DURING THE DAY ON TUE. BUT WITH WEAK
SHEAR THE COVERAGE SHOULD BE SPOTTY AND MAINLY CONFINED TO THE
MOUNTAINS AND FOOTHILLS. AS THE RIDGE STRENGTHENS OVER THE REGION
WEDNESDAY THROUGH FRIDAY...THE CAPE ALL BUT DISAPPEARS ON THE GFS.
THE ECMWF IS A LITTLE MORE UNSTABLE...BUT IN THIS CASE I THINK THE
GFS MAKES SENSE AND I ONLY HAVE SLIGHT CHANCE POPS OVER THE MTNS WED
AND THU AND NOTHING ON FRIDAY...WITH DRY CONDITIONS THROUGH THE
PERIOD AT THE LOWER ELEVATIONS. IN OTHER WORDS...A WELL BELOW CLIMO
CHANCE OF PCPN FOR EVERYONE. WITH HEIGHTS RISING...I BUMPED UP MAX
TEMPS A DEGREE OR TWO WHICH BRINGS MOST OF THE FOOTHILLS AND
PIEDMONT SOLIDLY INTO THE UPPER 80S ALL THREE DAYS WITH SOME 90S BY
FRIDAY.

&&

.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...VFR AS DRY AND QUIET HIGH PRESSURE BUILDS
INTO THE REGION FROM THE GREAT LAKES. WEAKER WIND PROFILES WILL
PRECLUDE GUSTS TODAY...EXCEPT FOR A FEW LOW-END GUSTS POSSIBLE AT
KAVL AFTER MIXING INCREASES LATER THIS MORNING. WINDS ACRS THE
PIEDMONT MAY BECOME VRB OR FAVOR A LGT SW DIR WITH A LEE TROF
SETTING UP THIS AFTN. A LIGHT N/NE WIND OR CALM TONIGHT WITH SOME
MID-HIGH CLOUDS BEGINNING TO STREAM IN FROM THE NW AFT
SUNSET...PRODUCING HIGH VFR CIGS DURING WEE MORNING HOURS.

OUTLOOK...WITH DRY HIGH PRES DOMINATING THE WEATHER ACRS THE REGION
THRU THE WEEKEND...NO SIGNIFICANT AVIATION CONCERNS ARE EXPECTED. A
RETURN TO DIURNAL THUNDERSTORMS IS EXPECTED FOR MONDAY THROUGH
WEDNESDAY WITH ASSOCIATED RESTRICTIONS IN THE VICINITY OF STORMS.

CONFIDENCE TABLE...

            11-17Z        17-23Z        23-05Z        05-11Z
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.

&&

.CLIMATE...
RECORD LOW TEMPERATURES THIS MORNING...

AVL...39 1925
CLT...45 2005
GSP...46 2005

&&

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

&&

$$
SYNOPSIS...DEO
NEAR TERM...ARK
SHORT TERM...MCAVOY
LONG TERM...MCAVOY
AVIATION...ARK
FIRE WEATHER...
CLIMATE...