Area Forecast Discussion
Issued by NWS Greer, SC

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000
FXUS62 KGSP 011136
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
736 AM EDT FRI MAY 1 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 TONIGHT/...
AS OF 630 AM...WATER VAPOR IMAGERY CONFIRMS THE LOCATION OF AN UPPER
LOW SPINNING OVER NC...MOVING SLOWLY OFF TO THE EAST. QUITE A BIT OF
PRECIP COVERAGE ACROSS THE NW PIEDMONT AND NRN NC...BUT NOT MUCH IN
THE GSP FCST AREA. THIS SHOULD CHANGE THRU MID MORNING AS PRECIP
OVER SW VA ROTATES DOWN ACROSS THE I-77 CORRIDOR.

FOR TODAY...THE UPPER LOW SHOULD ROTATE DOWN ACROSS THE WESTERN
CAROLINAS THIS MORNING AND THEN EVENTUALLY OFF THE OUTER BANKS OF NC
LATE THIS AFTERNOON AND EVENING. THE MOVEMENT OF THE UPPER LOW
SHOULD ALLOW SHOWER ACTIVITY TO DROP DOWN FROM THE N WHERE IT WILL
BE LESS IMPEDED BY DOWNSLOPE FLOW AND ABLE TO REACH ACROSS THE I-77
CORRIDOR. WILL INCREASE PRECIP CHANCES A BIT THERE BASED ON THE
CONSENSUS OF THE GUIDANCE. WILL ALSO HOLD ONTO THE CHANCE ON THE TN
BORDER INTO THE AFTERNOON. OTHERWISE...THE UPSTATE AND NE GEORGIA
SHOULD REMAIN DRY AS BETTER DOWNSLOPE WILL BE UNFAVORABLE. TEMPS
WERE NUDGED SLIGHTLY UPWARD. FOR TONIGHT...WITH THE UPPER LOW OUT OF
THE WAY...HIGH PRESSURE WILL SLIDE IN FROM THE NW...WITH CLEARING
SKY AND DRY AIR.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 215 AM EDT FRIDAY...THE SHORT TERM FCST PERIOD INITIALIZES
SATURDAY MORNING AMIDST RISING HEIGHT ALOFT AS BROAD UPSTREAM H5
RIDGE MIGRATES EAST.  AT THE SURFACE...1020MB SFC HIGH PRESSURE
STRETCHING FROM THE GREAT LAKES TO THE GULF COAST WILL PREVAIL...ALL
THE WHILE SLOWLY ADVECTING EASTWARD THROUGH THE DAY.  THUS...DEEP
LAYER RIDGING AND DEWPOINTS IN THE 40S WILL YIELD MOSTLY SUNNY SKIES
AND DRY WX ON SATURDAY WITH HIGHS TOPPING OUT A FEW DEGREES BELOW
NORMAL.  ABOVE MENTIONED RIDGING WILL PREVAIL YET AGAIN ON SUNDAY AS
SFC HIGH PRESSURE SHIFTS OVERHEAD...THEN SETS UP ALONG THE MID
ATLANTIC COAST LATE IN THE DAY.  THIS WILL YIELD RETURNING SOUTHERLY
WAA REGIME FOR THE LATER PART OF THE PERIOD WITH A FEW MODELS
SHOWING ENOUGH DEWPOINT MODERATION TO SUPPORT WEAK CONVECTIVE
CHANCES OVER THE NC HIGH TERRAIN SUNDAY AFTERNOON.  ALTHOUGH
MENTIONED IN THE FCST...POPS ARE CAPPED AT SLIGHT CHANCE LEVELS AS
RIDGING IS EXPECTED TO KEEP CONVECTION AT BAY FOR THE MOST PART.
POPS WILL LOWER SHARPLY INTO THE EVENING AS HEATING IS LOST.
TEMPERATURES ON SUNDAY WILL RETURN TO SLIGHTLY ABOVE NORMAL LEVELS.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 230 AM EDT FRIDAY...THE MEDIUM RANGE PERIOD INITIALIZES MONDAY
MORNING AMIDST BROAD FLAT RIDING ALOFT OVER MUCH OF THE DEEP
SOUTH...WHILE A 1027MB SFC HIGH REMAINS CENTERED OFF THE CAROLINA
COAST.  MOIST WAA REGIME WILL CONTINUE TO PREVAIL ON MONDAY WITH
DEWPOINTS RECOVERING BACK INTO THE LOWER/MID 50S BY PEAK HEATING.
MODELS CONTINUE TO PROG ISOLATED SHRA/TSRA ACROSS THE MTNS WHERE THE
BEST LAPSE RATES AND THUS INSTABILITY WILL RESIDE...WHILE OUTSIDE OF
THE MTNS ANY SUBSIDENCE IS EXPECTED TO HOLD.  THUS...THE FCST
FEATURES DIURNALLY TIMED POPS OVER THE NC MTNS MONDAY
AFTERNOON...WITH NO POPS MENTIONED ELSEWHERE.  THE PATTERN REALLY
DOESNT CHANGE ALL THAT MUCH ON TUESDAY...AND THROUGH THE REMAINDER
OF THE MEDIUM RANGE AS UPPER RIDGING PREVAILS...ALBEIT
WEAKER...WHILE THE SURFACE HIGH SHIFTS SLIGHTLY SOUTHEAST TOWARDS
BERMUDA.  DIURNALLY INDUCED AIRMASS SHRA/TSRA CONTINUES TO BE
MENTIONED EACH AFTERNOON FOR THE MTNS WITH SLIGHT/CHANCE LEVEL POPS
FEATURED.  THE FCST REMAINS DRY FOR THE PIEDMONT REGIONS OF
NC/SC...ALONG WITH MOST OF NORTHEAST GA THROUGH MIDWEEK.  POPS
FINALLY INTRUDE INTO THESE AREAS ON THURSDAY WHEN MODELS PROG MORE
FAVORABLE PROFILES FOR CONVECTION.  TEMPERATURES THROUGH THE PERIOD
WILL REMAIN A FEW DEGREES ABOVE CLIMO.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AT KCLT...VFR TO START WITH...BUT THERE IS SOME POTENTIAL FOR AN
MVFR CEILING DURING THE MID MORNING TO EARLY AFTERNOON AS SHOWER
ACTIVITY MOVES OVER THE TERMINAL. WILL INCLUDE A TEMPORARY MVFR
CEILING RESTRICION TO HANDLE THIS. ANY MVFR SHOULD RISE INTO THE
LOWER PART OF THE VFR RANGE AS THE BOUNDARY LAYER HEATS UP. WIND MAY
GUST OCCASIONALLY THRU THE AFTERNOON. DIRECTION IS EXPECTED TO
REMAIN NLY THRU THE PERIOD...BUT WILL GO LIGHT THIS EVENING WITH
SUNSET AND HIGH PRESSURE BUILDING EAST.

ELSEWHERE...AN MVFR CLOUD DECK HAD MOVED UP THE FR BROAD VALLEY...
SO A BKN MVFR WILL BE INCLUDED AT KAVL. SIMILAR TO KCLT...THERE IS A
CHANCE OF A BKN MVFR CEILING AT KHKY...BUT CONFIDENCE TOO LOW TO
INCLUDE IT. OTHERWISE...MAINLY SCT HIGH BASED STRATOCU. WINDS WILL
BE GUSTY FROM THE NW AT KAVL. OTHER SITES SHOULD REMAIN NW TO N.

OUTLOOK...RETURN FLOW MOISTURE WILL ONLY SLOWLY REDEVELOP EARLY NEXT
WEEK.

CONFIDENCE TABLE...

            11-17Z        17-23Z        23-05Z        05-06Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH  85%     HIGH  94%     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...CDG
NEAR TERM...PM
SHORT TERM...CDG
LONG TERM...CDG
AVIATION...PM



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