Area Forecast Discussion
Issued by NWS Greer, SC

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000
FXUS62 KGSP 020527
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
127 AM EDT SAT MAY 2 2015

.SYNOPSIS...
DEEP LAYER RIDGING WILL PREVAIL THROUGH MID WEEK. ALTHOUGH DRIER
CONDITIONS ARE EXPECTED...AN OCCASIONAL SHOWER OR THUNDERSTORM WILL
BE POSSIBLE DURING PEAK HEATING FROM SUNDAY THROUGH LATE WEEK...
MAINLY ACROSS THE MOUNTAINS. TEMPERATURES WILL MODERATE TO ABOVE
NORMAL LEVELS.

&&

.NEAR TERM /THROUGH TODAY/...
AS OF 130 AM...CLEAR SKY AND LIGHT WIND ACROSS THE ENTIRE FCST AREA.
STILL SOME FAIRLY LARGE DEWPT DEPRESSIONS...SO NO IMMEDIATE CONCERN
FOR FOG. HOWEVER...THERE SHOULD BE SOME PATCHES OF FOG AROUND
DAYBREAK ACROSS MAINLY THE WESTERN NC PIEDMONT AND IN THE MTN
VALLEYS. TEMPS LOOK OK.

REMAINDER OF PREVIOUS DISCUSSION...

SFC HIGH PRESSURE WILL GRADUALLY SETTLE OVER THE REGION FROM THE
WEST THROUGH SATURDAY AS PROFILES STEADILY DRY OUT AND THE PRES
GRADIENT WEAKENS. THERE IS ONE WEAK SHORTWAVE IN THE NW FLOW ALOFT
THAT WILL CROSS THE SRN APPALACHIANS LATE SAT AFTN. IN ADDITION...
ENOUGH LOW LEVEL CONVERGENCE COULD FORM TO PRODUCE ISOLD ERN
ESCARPMENT SHOWERS CIRCA 21Z...BUT COVERAGE SHOULD REMAIN MINIMAL
GIVEN THE RELATIVELY DRY BOUNDARY LAYER. MAX TEMPS WILL RECOVER
CLOSER TO CLIMO FOR SAT AFTN.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...
AS OF 200 PM FRI...HIGH PRESSURE CENTERED OVER THE SRN APPALACHIANS
SATURDAY NIGHT WILL MOVE OFF THE CAROLINA COAST BY SUNDAY EVENING.
LIGHT SOUTHERLY FLOW SHOULD RETURN ON SUNDAY TO AID LIFT AS WELL AS
WARMING...AND A MINOR SHORTWAVE PASSING OVERHEAD MIGHT PROVIDE A
SLIGHT BOOST AS WELL. HOWEVER MIDLEVEL LAPSE RATES REMAIN MARGINAL
BENEATH A MEAN UPPER RIDGE. LOW POPS OVER THE HIGHER TERRAIN STILL
LOOK APPROPRIATE. THE SHORTWAVE BECOMES STAGNANT OVER THE AREA SUNDAY
NIGHT WHILE THE HIGH REMAINS OFFSHORE. A SLIGHTLY STRONGER LLVL
GRADIENT WILL ALLOW EVEN BETTER WARM/MOIST FLOW...WHILE THE COOLER
AIR IN THE MID-UPPER LEVELS WILL IMPROVE LAPSE RATES. INSTABILITY
WILL BE GREATER ON MONDAY...AS WILL POPS...THOUGH THEY GENERALLY WILL
REMAIN OVER THE NW HALF OF THE CWFA. DEEP SHEAR IS RATHER WEAK BOTH
DAYS...LOW ENOUGH TO MINIMIZE ORGANIZATION OF ANY STORMS THAT DO FORM
AND KEEP SEVERE WX CHANCES MINIMAL. ON THE OTHER HAND IT IS LIKELY
HIGH ENOUGH TO MITIGATE A PULSE THREAT OR HEAVY RAIN THREAT DUE TO
SLOW CELL MOTION. TEMPS WILL BE AROUND NORMAL SUNDAY...AND SLIGHTLY
ABOVE NORMAL ON MONDAY.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 215 PM FRIDAY...AN UPPER RIDGE BUILDS ACROSS THE AREA AND
REMAINS IN PLACE THROUGH THE PERIOD. AN UPPER LOW DEVELOPS OVER THE
BAHAMAS AND MOVES NORTH TOWARD THE CAROLINA COAST LATE IN THE
PERIOD. AT THE SFC...HIGH PRESSURE REMAINS ACROSS THE AREA THRU THE
PERIOD KEEPING A BACK DOOR COLD FRONT FROM MOVING SOUTH INTO THE
AREA EARLY IN THE PERIOD...WHILE A HYBRID LOW DEVELOPS OVER THE
BAHAMAS AND APPROACHES THE CAROLINA COAST BY THE END OF THE PERIOD.
THE GUIDANCE DOES DIFFER IN THE TRACK OF THE LOW WITH THE 01/00Z
ECMWF SHOWING IT MAKING LANDFALL NEAR CAPE LOOKOUT...WHILE THE GFS
KEEPS IT OFF SHORE THROUGHOUT. EITHER WAY...THERE WILL BE LITTLE
EFFECT FROM THIS SYSTEM ON THE SENSIBLE WX ACROSS OUR CWFA. THE MAIN
WEATHER FEATURE WILL BE THE DIURNAL ISOLATED TO SCT CONVECTION EACH
DAY MAINLY ACROSS THE MTNS. CONVECTIVE CHC DOES INCREASE LATE IN THE
PERIOD OUTSIDE OF THE MTNS AS INSTABILITY...THOUGH WEAK...DOES BUILD
EACH DAY AND MID LEVEL SUBSIDENCE INVERSION DIMINISHES. TEMPS START
OUT A LITTLE ABOVE NORMAL AND RISE A FEW DEGREES THRU THE PERIOD.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...VFR CONDITIONS EXPECTED THROUGH THE
PERIOD...ALONG WITH A LIGHT N OR NW WIND. THERE IS A SMALL CHANCE OF
SOME MVFR FOG AT THE TERMINALS AROUND DAYBREAK...BUT THAT WAS NOT
INDICATED IN ANY OF THE GUIDANCE...AND SO IT WILL BE LEFT OUT OF THE
TAFS. ON SATURDAY AFTERNOON...EXPECT A FEW HIGH BASED STRATOCU TO
DEVELOP...BUT THAT SHOULD DISSIPATE WITH SUNSET. WIND WILL REMAIN
GENERALLY LIGHT FROM THE NW TO NW.

OUTLOOK...MAINLY DRY CONDITIONS WILL PERSIST THROUGH THE PERIOD...
BUT WITH RETURN FLOW MOISTURE VERY SLOWLY REDEVELOPING OVER THE MTNS
THROUGH EARLY NEXT WEEK.

CONFIDENCE TABLE...

            05-11Z        11-17Z        17-23Z        23-00Z
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

&&

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

&&

$$
SYNOPSIS...RWH
NEAR TERM...HG/JDL/PM
SHORT TERM...WIMBERLEY
LONG TERM...RWH
AVIATION...PM



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