Area Forecast Discussion
Issued by NWS Greer, SC

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000
FXUS62 KGSP 290228
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1028 PM EDT SUN SEP 28 2014

.SYNOPSIS...
MOISTURE WILL INCREASE ACROSS THE REGION THROUGH TOMORROW AS
LOW PRESSURE TRACKS ALONG THE COAST. DRY HIGH PRESSURE WILL THEN
BUILD IN ON TUESDAY AND LINGER THROUGH THURSDAY. A COLD FRONT WILL
ARRIVE FROM THE NORTHWEST ON FRIDAY.

&&

.NEAR TERM /THROUGH MONDAY/...
AS OF 1025 PM...AREAS OF SPRINKLES INCREASING THIS EVENING EVEN AS
THE SHOWERS REMAIN SPARSE. EXPECT THE SPRINKLES TO FILL IN ACROSS
THE AREA OVERNIGHT AS THE SHOWERS ONLY SLOWLY INCREASE IN COVERAGE
ACROSS THE SRN AND WRN CWFA. OTHERWISE...FCST REASONING STILL
UNCHANGED AS SHOWERS INCREASE IN COVERAGE AFTER MIDNIGHT WITH
NUMEROUS COVERAGE ACROSS MOST OF THE AREA BY DAYBREAK AND WIDESPREAD
COVERAGE OVER THE UPPER SAV RIVER VALLEY AND SRN UPSTATE. ALSO
UNCHANGED IS THE EXPECTED LIGHT QPF AS GULF COAST CONVECTION
CONTINUES TO DISRUPT MOISTURE FLUX INTO THE AREA. ONLY MINOR CHANGES
NEEDED FOR CURRENT CONDITIONS.

AS OF 745 PM...RADAR STILL RELATIVELY QUITE WITH ONLY A FEW AREAS OF
SPRINKLES AT BEST. THAT SAID...THERE IS A BAND OF PRECIP BEGINNING
TO DEVELOP SOUTH OF I-85 ACROSS GA AND SPREADING INTO THE SRN
UPSTATE. THIS AREA IS WHERE THE LATEST NAM SHOWS THE BEST PRECIP CHC
OVERNIGHT...SO WILL HAVE TO WATCH THIS FOR DEVELOPMENT. HOWEVER...
THE OVERALL TREND OF THE LATEST GUIDANCE IS TO KEEP ANY SIGNIFICANT
PRECIP WELL SOUTH OF THE AREA AS GULF COAST CONVECTION ROBS THE AREA
OF SIGNIFICANT MOISTURE FLUX. IN FACT...THE LATEST QPF GUIDANCE FROM
WPC HAS SHIFTED ANY SIGNIFICANT RAINFALL OVERNIGHT SOUTH AND EAST OF
THE AREA IN LINE WITH THESE TRENDS. STILL EXPECT GOOD COVERAGE OF
RAIN DEVELOPING OVERNIGHT AND CONTINUING THRU THE DAY MON.
HOWEVER...RAINFALL WILL BE MUCH LIGHTER. HAVE TAKEN THESE TRENDS
INTO ACCOUNT WITH THE UPDATE SIGNIFICANTLY CHANGING POP THIS EVENING
AND QPF THRU MON. OTHERWISE...GOING FCST IS GENERALLY ON TRACK WITH
UPDATES FOR CURRENT CONDITIONS.

AS OF 445 PM...RADAR IS STILL RELATIVELY QUIET WITH ONLY A FEW AREAS
OF SPRINKLES AT MOST. HAVE SLOWED PRECIP ONSET THIS AFTERNOON AND
EARLY EVENING IN LINE WITH OBS AND LATEST GUIDANCE. HOWEVER...ALLOW
PRECIP TO QUICKLY RAMP UP LATER THIS EVENING IN LINE WITH GOING
FCST. HAVE MADE ADJUSTMENTS TO OTHER FIELDS BASED ON CURRENT
CONDITIONS.

AS OF 210 PM...SCATTERED LIGHT RETURNS ARE BEGINNING TO APPEAR ON THE
88D ACROSS THE FAR SW/RN ZONES CURRENTLY. MECH LIFT AND CONTINUED
ATL MOISTURE FLUX WILL COMBINE WITH GOM MOISTURE THIS AFTERNOON AND
EVENING AND PRECIP WILL REMAIN FOCUSED ACROSS THE SW NC MTNS AND NE
GA...WITH SOME DEVELOPMENT ACROSS THE NW/RN UPSTATE AND ESCARPMENT
POSSIBLE. RAINFALL AMOUNTS WILL BE LIGHT INTO THE EVENING.

A WEAK GOM COASTAL LOW WILL CONTINUE TO BECOME A LITTLE MORE
ORGANIZED OVERNIGHT AND BEGIN SLOWLY TRACKING ENE. THIS WILL BRING
IN MORE WIDESPREAD PRECIP ACROSS MOST ZONES AFT 09Z OR SO. NOT
SEEING A GOOD CHANCE FOR CONVECTIVE PRECIP...AS THE MODELS HAVE
BACKED OFF ON THEIR SPURIOUS DEFORMATION FORCING WHILE MAINTAINING A
MODESTLY STRONG SFC WEDGE OVER THE FCST AREA. THROUGH
DAYBREAK...PRECIP AMOUNTS SHOULD BE THE HIGHEST ACROSS THE SRN
UPSTATE AND NE GA...WHERE ARND 0.25 INCHES IS POSSIBLE. MIN TEMPS
WILL REMAIN A COUPLE CATS ABOVE NORMAL IN A HIGHLY MOIST ENV.

THE AFOREMENTIONED COASTAL LOW WILL BE PUSHING OFF THE SRN GA COAST BY
THE END OF THE MON DAY PERIOD. THE BEST SYNOPTIC FORCING WITH THIS
FEATURE WILL REMAIN WELL SOUTH OF THE AREA...WITH SOME QPF
ENHANCEMENT ATOP THE SFC WEDGE MAINLY BEFORE 18Z. MOST PLACES WILL
SEE BETWEEN A QUARTER TO ONE HALF INCH N/S OF NEW PRECIP THROUGH
THIS TIME...WITH AN ADDITIONAL FEW TENTHS DURING THE AFTERNOON.
THUS...THE EVENT TOTAL PRECIP THROUGH 00Z MON WILL LIKELY BE ABOUT
THREE QUARTERS OF AN INCH TO AN INCH SOUTH...TO ARND A HALF INCH
NORTH. CONTINUED UPSLOPE H85 FLOW WILL INSTIGATE -SHRA AND POSSIBLY
SOME GENERAL THUNDER ACROSS THE NC MTNS MON AFTERNOON...WITH THIN
CAPE NOTED BTW H8/H65. WITH CONTINUOUS PRECIP...MAX TEMPS WILL
BE HELD A FEW CATS BELOW NORMAL. GENERALLY U60S NON/MTNS AND ACROSS
MTN VALLEYS AS WELL.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 200 PM SUNDAY...A POSITIVE TILT UPPER WAVE DIGGING SE THROUGH
THE GREAT LAKES MON NIGHT WILL BRUSH THE NRN TIER OF THE FORECAST
AREA ON TUE. HOWEVER...DEEP LAYER DRYING FROM THE WEST WILL PRECEDE
THE WAVE AS THE COASTAL TROUGH PULLS AWAY TO THE EAST. THIS SHOULD
LEAD TO A RAPID END TO ANY LINGERING LIGHT RAIN/SHOWERS MON
NIGHT...AND THEN NOTHING MORE THAN LOW END ISOLD SHRA POPS ALONG THE
BLUE RIDGE WITH THE WAVE PASSAGE TUE AS MOST AREAS STAY DRY.

A SHALLOW UPPER RIDGE WILL CROSS THE REGION FROM THE WEST TUE NIGHT
THROUGH WED...AS A SFC FRONTAL BOUNDARY LAYS OVER TO THE N. THE
FORECAST AREA WILL REMAIN DRY...WITH LITTLE MORE THAN A SCATTERED
STRATOCUMULUS FIELD IN LINE WITH LINGERING 850 MB MOISTURE UNDER THE
RIDGE. EXPECT CONTINUED ABOVE NORMAL MINS...WITH MAXES SLOWLY
RETURNING TO NEAR CLIMO BY WED AFTN WITH INMPROVING INSULATION
DESPITE THE NRLY/EASTERLY FLOW AT LOW LEVELS.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 1230 PM SUNDAY...WITH THE LATEST AVAILABLE MEDIUM RANGE MODEL
SUPPORT OF LINGERING DEEP LAYERED RIDGING ATOP THE CWFA TO START OFF
THE PERIOD...THE INHERITED DRY AND SEASONABLY MILD THURSDAY WILL
REMAIN AS IS. FRIDAY/S SENSIBLE WX FORECAST REMAINS PRETTY MUCH ON
TRACK AS WELL FEATURING THE PASSAGE OF A MODERATELY FORCED COLD
FRONT...PROBABLY AIDING IN A ROUND OF DEEP CONVECTION FOR MOST
PLACES FRIDAY INTO FRIDAY EVENING. IN THE WAKE OF THE FROPA...AND
AN EASTERN CONUS L/WV TROUGH PROGGED TO SET UP NEXT WEEKEND...WILL
FEATURE A DRY DAYS 6/7 WITH TEMPERATURES A CATEGORY OR TWO BELOW
NORMAL.

&&

.AVIATION /03Z MONDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...LATEST GUIDANCE SHOWS GULF COASTAL
CONVECTION ROBBING THE AREA OF SIGNIFICANT MOISTURE FLUX CUTTING
PRECIP CHC FOR WIDESPREAD HEAVY PRECIP THRU THE PERIOD. THAT SAID...
THERE WILL BE QUITE A BIT OF CLOUDS AND OFF AND ON LIGHT PRECIP
BEGINNING LATE TONIGHT AND CONTINUING THRU THE DAY MON. WITH THE
DECREASE IN COVERAGE AND INTENSITY...RESTRICTIONS ARE BECOMING LESS
LIKELY AS WELL. THERE IS A SMALL CHC OF MVFR CIGS AND/OR VSBY NEAR
DAYBREAK. HOWEVER...WITH THE DECREASE IN POTENTIAL...HAVE REMOVED
ANY RESTRICTIONS FROM THE TAFS. CANNOT RULE OUT SOME LOW VFR AROUND
THAT TIME THOUGH. GENERALLY LIGHT N TO NE WINDS CONTINUE THRU THE
PERIOD. KAVL THE EXCEPTION WITH LIGHT NLY WIND BECOMING LIGHT SLY
MON AFTERNOON.

OUTLOOK...PRECIPITATION CHANCES WILL DECREASE RAPIDLY MON NITE...
PERHAPS INDUCING DENSE FG FORMATION ACROSS THE HIGHER TERRAIN
VALLEYS. THE ATMOS DRIES OUT TUE INTO FRI WITH MORNING VSBY CONCERNS
REMAINING ACROSS THE MTNS AND FOOTHILLS.

CONFIDENCE TABLE...

            02-08Z        08-14Z        14-20Z        20-02Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH  97%     HIGH 100%
KAVL       HIGH  86%     LOW   59%     HIGH  90%     HIGH  98%
KHKY       HIGH  94%     HIGH  83%     HIGH  98%     HIGH  97%
KGMU       HIGH 100%     HIGH 100%     HIGH  97%     HIGH  94%
KAND       HIGH 100%     HIGH  81%     HIGH  90%     HIGH  95%

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...CSH
NEAR TERM...RWH/SBK
SHORT TERM...HG
LONG TERM...CSH
AVIATION...RWH






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