Area Forecast Discussion
Issued by NWS Greer, SC

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000
FXUS62 KGSP 060602
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
202 AM EDT MON JUL 6 2015

.SYNOPSIS...
AS AN UPPER LEVEL LOW PRESSURE SYSTEM DEPARTS THE REGION...SLIGHTLY
DRIER AIR ARRIVES FROM THE WEST TODAY. LOW LEVEL MOISTURE WILL
REMAIN THROUGH THE WEEK...WITH A RETURN TO A MORE NORMAL PATTERN
FEATURINGSCATTERED AFTERNOON AND EVENING THUNDERSTORMS EACH DAY OF
THE WEEK. A COLD FRONT WILL APPROACH FROM THE NORTHWEST TOWARD
NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TODAY/...
AS OF 145 AM MON...THE UPPER TROUGH THAT HAS LINGERED OVER THE CWFA
THE PAST COUPLE OF DAYS IS STARTING TO LOSE INFLUENCE AS IT DRIFTS
NEWD...EVENTUALLY GETTING ABSORBED BACK INTO THE NRN STREAM FLOW AS
A BROADER SHORTWAVE ENTERS THE UPPER MISSISSIPPI VALLEY. THE BEST
DPVA IS ALREADY OFF TO OUR NORTHEAST. SHOWER ACTIVITY HAS WANED OVER
THE WRN CAROLINAS...WITH RADAR RETURNS EVEN DIMINISHING OVER THE NC
MTNS. MESO MODELS GENERALLY FEATURE NO NEW DEVELOPMENT UNTIL AFTER
DAWN. SO FOR THE EARLY MORNING HOURS ANY CHANCE OF SHOWERS PRODUCING
ACCUMULATION WILL BE CONFINED TO THE MTNS WHERE SLIGHT UPSLOPING
WILL PROVIDE A LITTLE EXTRA FORCING. HOWEVER A FEW SPRINKLES CANNOT
BE RULED OUT ELSEWHERE IN THE AREA.

AS OF SUNDAY AFTN...THE UPPER TROUGH WILL MOVE SLOWLY EAST ON
MONDAY...WITH MORE OF THE FORECAST AREA GETTING INTO AN NVA REGION
THROUGH THE DAY. WITH LESS CLOUDS AND MORE HEATING...CONVECTION MAY
DEVELOP EASTWARD OFF THE BLUE RIDGE MONDAY AFTN...ESPECIALLY WITH
LOW LEVEL CONVERGENCE FORMING ALONG THE ERN SLOPES AND IN A LEE
TROUGH. LAPSE RATES STEEPEN A BIT MONDAY AFTERNOON...BUT WARM AIR
ALOFT IN PROFILES SHOULD LIMIT CAPE SOMEWHAT. 850 TO 500 MB LAPSE
RATES SHOULD STILL MANAGE TO REACH 6.5 DEG C/KM...AND WITH MID LEVEL
DRY AIR WRAPPING IN...A GENERAL TSTM THREAT WITH LOCALLY GUSTY WINDS
SHOULD ARISE. TEMPS WILL WARM BACK CLOSE TO CLIMO.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
AT 230 PM EDT SUNDAY...ON MONDAY EVENING A FILLING UPPER LOW AND
ASSOCIATED VORT LOBE WILL BE LIFTING NE ACROSS THE CENTRAL
APPALACHIANS AND AWAY FROM OUR AREA. NEARLY ZONAL FLOW WILL BE OVER
THE SOUTHERN TIER OF STATES...WITH AN ELONGATED SHORTWAVE MOVING
INTO THE OF AND MID MS RIVER VALLEYS. BY TUESDAY NIGHT AN UPPER
RIDGE OVER THE WESTERN ATLANTIC BUILDS WEST OVER THE SOUTHEASTERN
STATES. THIS RESULTS IN OHIO VALLEY SHORTWAVE ENERGY BEING CHANNELED
EASTWARD TOWARD CHESAPEAKE BAY THROUGH WEDNESDAY...AND REMAINING
NORTH OF OUR AREA.

AT THE SURFACE...MOISTURE ASSOCIATED WITH THE UPPER LOW WILL BE OVER
THE MID ATLANTIC REGION MONDAY EVENING...WITH SLIGHTLY DRIER AIR
WORKING INTO OUR AREA IN WAKE OF THE UPPER LOW. THIS RELATIVE LULL
IN MOISTURE LAST THROUGH TUESDAY NIGHT...FOLLOWED BY A SUBSTANTIAL
MOISTURE INCREASE FROM THE NORTH ON WEDNESDAY...SOUTH OF WEAKENING
AND DECELERATING COLD FRONT IN THE OH RIVER VALLEY.

ALTHOUGH A RELATIVE DRYING TREND IS EXPECTED EARLY ON...ENOUGH
MOISTURE AND INSTABILITY WILL REMAIN FOR PRIMARILY DIURNALLY DRIVEN
CONVECTION ON MONDAY EVENING AND TUESDAY. WITH INCREASING MOISTURE IN
NC ON WEDNESDAY...PRECIPITATION COVERAGE SHOULD BE MORE WIDESPREAD
THERE...BUT INSTABILITY MAY BE MORE LIMITED DUE TO CLOUD COVER
LIMITING HEATING. TEMPERATURES WILL RUN NEAR NORMAL...EXCEPT ALONG
INTERSTATE 40 ON WEDNESDAY...WHERE CLOUD COVER WILL LIMIT DAYTIME
HEATING.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AT 230 PM EDT SUNDAY...ON THURSDAY AN UPPER RIDGE WILL EXTEND FROM
THE WESTERN ATLANTIC TO TX...WITH ZONAL FLOW TO THE NORTH FROM THE
ROCKIES TO ME. THE GFS STRENGTHENS THE RIDGE OVER THE EASTERN USA
INTO THE WEEKEND...WHILE THE ECMWF RETROGRADES IT TO THE SOUTHERN
ROCKIES...ALLOWING FORM SOME SHALLOW TROUGHING OVER THE EAST.

AT THE SURFACE...HIGH PRESSURE WILL BE CENTERED OVER THE SOUTHERN
APPALACHIANS ON THURSDAY...WITH LEE TROUGHING OVER THE PIEDMONT...
AND A STATIONARY FRONT FROM THE OH RIVER VALLEY TO THE DELMARVA
PENINSULA. THIS PATTERN PERSIST THROUGH NEXT SUNDAY. MOISTURE TO THE
SOUTH OF THE BOUNDARY WILL BE GREATER OVER NC THAN SC AND GA. THE
MODELS SHOWS MODEST INSTABILITY...BUT GENERALLY VERY LIGHT STEERING
FLOW...SUGGESTING HEAVY RAINFALL WHERE LIFT CAN BE GENERATED.
TEMPERATURES WILL TREND UPWARD TO ABOVE NORMAL AS HEIGHTS RISE ALOFT.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...UPPER LOW IS BEGINNING TO LIFT OUT OF THE
REGION...BUT THE CYCLONIC FLOW AND ELEVATED MOISTURE ARE CONTINUING
TO RESULT IN ABUNDANT MID-HIGH CLOUD DECKS. THESE WILL BECOME LESS
WIDESPREAD THRU THE MRNG. BETWEEN NOW AND DAYBREAK...A FEW SPRINKLES
ARE POSSIBLE HERE AND THERE AS WELL. GUIDANCE SUGGESTS CIGS WILL
REMAIN VFR EXCEPT OVER THE HIGHER ELEVATIONS OF THE MTNS. SPOTTY
FEW-SCT IFR LEVEL CLOUD REPORTS ARE COMING IN FROM SOME AREA OBS
SITES...POSSIBLY FORMING OVER AREAS THAT SAW RAINFALL ON SUNDAY
AND/OR IN UPSLOPE SWLY LOW LEVEL FLOW. SOME MODELS INDICATE A BAND
OF IFR CIGS AND/OR FOG DEVELOPING OVER THE SC MIDLANDS AND ADVECTING
NWD...BUT THE CHC SEEMS LOW IN LIGHT OF RATHER DRY CONDITIONS.
NONETHELESS AT KCLT I HAVE INCLUDED A TEMPO FOR A 1000 FT CIG NEAR
DAYBREAK. SOME MVFR FOG IS EXPECTED TO FORM OVER THE USUALLY FOGGY
SITES AROUND THE AREA...INCLUDING KAVL/KAND/KHKY. DURING THE
DAY...FLOW WILL CONTINUE TO BE GENERALLY SW EAST OF THE MTNS.
DIURNALLY DRIVEN TSRA MAY FORM INVOF THE BLUE RIDGE ESCARPMENT AND
PROPAGATE EWD THRU THE AFTN. PROB30 MENTION AT ALL SITES WITH TIMING
FOLLOWING CONSENSUS OF CONVECTION ALLOWING MODELS AND THE NAM.

OUTLOOK...THE WEATHER REGIME WILL RETURN TO A MORE TYPICAL DIURNAL
SUMMERTIME PATTERN THROUGH THE WEEK. THIS WILL MEAN SCATTERED
AFTN/EVENING THUNDERSTORMS OVER THE AREA...MAINLY IN THE MTNS...WITH
ASSOCIATED RESTRICTIONS UNDER THE HEAVIEST SHOWERS...AND SPOTTY LOW
CLOUDS AND FOG THE FOLLOWING MORNING.

CONFIDENCE TABLE...

            06-12Z        12-18Z        18-24Z        00-06Z
KCLT       HIGH  99%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH  95%     HIGH  97%     HIGH 100%     HIGH 100%
KHKY       HIGH  94%     HIGH  97%     HIGH 100%     HIGH 100%
KGMU       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAND       HIGH  99%     HIGH  88%     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...WIMBERLEY
NEAR TERM...HG/WIMBERLEY
SHORT TERM...JAT
LONG TERM...JAT
AVIATION...WIMBERLEY



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