Area Forecast Discussion
Issued by NWS Greer, SC

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000
FXUS62 KGSP 011210
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
810 AM EDT FRI AUG 1 2014

.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN WEDGED OVER THE CAROLINAS
THROUGH SATURDAY AS AN UPPER TROUGH REMAINS CENTERED TO OUR WEST. TO
THE EAST...A FRONT WILL REMAIN NEARLY STATIONARY ALONG THE COAST
ALLOWING DEEP ATLANTIC MOISTURE TO CONTINUE TO SPREAD OVER THE AREA.
CONDITIONS ARE EXPECTED TO RETURN TO MORE TYPICAL LATE SUMMER
CONDITIONS BY THE MIDDLE OF NEXT WEEK AS THE BERMUDA STRENGTHENS TO OUR
EAST.

&&

.NEAR TERM /THROUGH TONIGHT/...
1205 UTC UPDATED...POPS HAVE BEEN ADJUSTED PER RADAR TRENDS...WITH A
DECREASE IN THE MOUNTAINS. POPS WILL BE ALLOWED TO INCREASE THERE
THIS AFTERNOON AS HEATING OCCURS...BUT NOT TO THE EXTENT THAT
EXISTED AS THE UPPER LEVEL SYSTEM WENT BY THIS MORNING.

MORNING UPDATE...PRECIP REMAIN ESTABLISHED ACROSS THE ERN ZONES
OUTSIDE OF THE WATCH AREA...WHICH IS GOOD AS FFG IS HIGHER IN THAT
AREA. DUAL POL FFMP RATIOS HAVE COME DOWN ACROSS THE NRN UPSTATE AND
RIVER GAUGES ON THE PACOLET RIVER AND GILDER CREEK HAVE COME DOWN.
THE MIDDLE TYGER RIVER IS STILL ELEVATED...BUT HEADWAITER RAIN HAS
DIMINISHED SIGFNTLY. DON/T EXPECT MUCH IN THE WAY OF HYDRO CONCERNS
THIS MORNING...BUT AN SPS/ADV IS NOT OUT OF THE QUESTION ACROSS THE
ERN ZONES WHERE CONVECTION IS DEVELOPING DEEP ALREADY. A COUPLE OF
THESE ERN STORMS COULD BECOME QUITE STRONG TO SEVERE OVER THE NEXT
FEW HRS. POPS AND QPF WERE ONCE AGAIN ADJ EAST TO ACCOUNT FOR RECENT
TRENDS.

430 AM EDT UPDATE...RAIN CONTINUES TO REFORM ACROSS THE NRN UPSTATE
PRODUCING A GOOD AMOUNT OF PRECIP WITHIN THE PAST 3 HRS. DUAL POL
FFMP HAS 3-HR RATIOS APPROACHING 85 PERCENT. THE ADVISORY IS
COVERING THIS AREA WELL...BUT THIS MAY NEED TO BE UPGRADED TO A
WARNING BY DAYBREAK IF THE RAINFALL DOESN/T SHIFT. GOOD CLEARING IS
SEEN TO THE WEST WHICH WAS EXPECTED AND POPS HAVE ADJ A LITTLE MORE
DOWN IN THAT AREA. THE ESCARPMENT AND NC PIEDMONT AREAS ARE NOW
SEEING STEADY MODERATE RAINFALL...AREAS WHICH HAVE RELATIVELY HIGH
FFG COMPARED TO THE UPSTATE.

AS OF 230 AM EDT...A LIGHT TO MODERATE PRECIP SHIELD HAS BEGUN TO
DEVELOP MORE INTO THE NRN MTNS AND FOOTHILLS AS WELL THE LOWER NC
PIEDMONT. INSTANTANEOUS RATES ARE VARYING BTW ONE AND TWO
IN/HR...WITH THE HIGHEST AMOUNTS OCCURRING ALONG THE I-85 CORRIDOR
FROM BLACKSBURG TO THE CLT METRO. EXPECT THIS NORTHWARD TREND TO
SLOWLY CONTINUE THROUGH THE PERIOD. THE GOOD THING IS THE HEAVIEST
DOWNPOURS ARE CONTINUING TO MOVE AND ARE NOT OCCURRING WHERE THE
GREATEST RAINFALL FELL PREVIOUSLY. THERE COULD BE AN ISOL HYDRO
THREAT THROUGH THE MORNING...BUT THE LACK OF DEEP CONVECTION HAS
LIMITED THIS POTENTIAL....YET SEE NO NEED TO EXPIRE OF THE FFA WITH
AN ONGOING PRECIP EVENT.

THINGS SHOULD BEGIN TO IMPROVE PRECIP/WISE THROUGH THE DAY WITH ULVL
ENERGY TRANSITING NE WHILE A NEW TROF AXIS DEVELOPS TO THE WEST OF
THE FA. THERE WILL BE WANING ATL MOISTURE AND SOME CONTINUED ISEN
LIFT OVER A WEAKENING SFC RIDGE...BUT DEEP CONVECTIVE ENHANCEMENT
AND ANCHORING CELLS ARE NOT FAVORED THIS AFTERNOON. THE LLVL FLOW
WILL BECOME WEAK THROUGH H7 AND AS THE WEDGE BNDRY LOOSENS OVERALL
MOISTURE FLUX WILL BE REDUCED THROUGH THE AFTERNOON...BUT THERE WILL
STILL BE A THREAT FOR PULSE TSTMS WITH HEAVY RAINFALL IN AREAS OF
GREATER INSTABILITY. A STATIONARY FRONT WILL REMAIN TO SE OF THE FA
OVERNIGHT...ROBING MOISTURE INTO THE AREA AS DEEP CONVECTION FIRES
ALONG THE COAST. PLENTY OF CLOUD COVER AND LINGERING PRECIP WILL
HOLD MAX TEMPS ARND 10-12 DEGREES BELOW NORMAL...BUT AREAS OF DIFF
HEATING COULD CREATE A BUST POTENTIAL. MINS WILL REMAIN A FEW
DEGREES BELOW NORMAL...MID TO UPPER 60S NON/MTNS AND L60S MTN
VALLEYS.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 220 AM EDT FRIDAY...THE SHORT TERM FCST PICKS UP AT 12Z ON
SATURDAY WITH THE WET PATTERN EXPECTED TO CONTINUE THROUGH EARLY
NEXT WEEK. THE UPPER TROUGH AXIS WILL REMAIN WEST OF THE
APPALACHIANS THRU THE WEEKEND AND GRADUALLY DRIFT EASTWARD EARLY
NEXT WEEK...DEAMPLIFY A BIT...AND TAKE ON A MORE POSITIVE TILT.

ON SATURDAY...AS THE WEDGE PATTERN PERSISTS DEEP LYR MOISTURE WILL
REMAIN OVER THE CWFA WITH THE HIGHEST PWAT VALUES EXPECTED OVER THE
SOUTHERN AND EASTERN ZONES. THE LATEST RUNS OF THE MESOSCALE MODELS
INDICATE THAT THE GREATEST QPF IS MORE LIKELY SAT AFTERNOON/EVENING
AS NUMEROUS LOBES OF PVA ROTATE AROUND THE UPPER TROF AND OVER THE
FCST AREA. THIS COUPLED WITH THE PERSISTENT ISENTROPIC UPGLIDE
SHOULD PRODUCE AT LEAST ANOTHER QUARTER TO ONE INCH OF RAINFALL OVER
THE CWFA BY EARLY SUN.

ON SUNDAY...A WEAK COLD FRONT WILL TRY AND PUSH ITS WAY INTO THE
WESTERN CAROLINAS FROM THE NW BUT WILL LIKELY STALL SOMEWHERE OVER
THE NC PIEDMONT WITH DRIER AIR BEHIND IT. OVERALL QPF POTENTIAL DOES
NOT LOOK AS FAVORABLE OVER MOST OF THE CWFA WITH THE GREATEST
AMOUNTS LIKELY JUST TO OUR SOUTH AND EAST ALONG THE STALLED BNDY.
THE AXIS OF HEAVIER PRECIP COULD OF COURSE SHIFT DEPENDING ON HOW
FAR SOUTH THE BNDY ACTUALLY MAKES IT. AT ANY RATE...I KEPT POPS AT
HIGH END CHANCE TO LIKELY THRU EARLY MONDAY WITH VALUES TAPERING
OFF FROM THE NW TO SE BY THE END OF MY PERIOD 12Z MONDAY. TEMPS WILL
VARY LITTLE FROM DAY TO DAY WITH HIGHS WELL BELOW NORMAL AND LOWS
NEAR NORMAL.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 1220 AM FRIDAY...THIS MEDIUM RANGE PERIOD BEGINNING AT 12Z
MONDAY WITH THE UPPER AIR PATTERN WITH A TROUGH AXIS WEST OF THE
APPALACHIANS. THIS TROUGH WILL GRADUALLY TRANSITION INTO MORE ZONAL
WEST TO EAST FLOW IN MID WEEK. AS THE TROUGH BREAKS DOWN...A WEAK
UPPER LOW WILL BE LEFT OVER THE LOWER MISSISSIPPI VALLEY. AS THE
GENERAL WESTERLY FLOW INCREASES IN MID WEEK...OUR AIRMASS WILL
BECOME DRIER AND TEMPS WILL RETURN TO NEAR NORMAL. ON MONDAY...THE
STALLED OUT SURFACE FRONT FROM NRN FL TO ALONG THE CAROLINA COAST
WILL HAVE WEAK LOWS RIDING NE ALONG THE FRONT.  IT APPEARS THE
TROPICAL LOW BERTHA IS FORECAST TO BE EAST OF THE CAROLINAS OUT
TOWARD BERMUDA ON TUESDAY AS IT TURNS FROM NW TO N THEN NE AVOIDING
THE EAST COAST. BY WED AND THUR WE CAN EXPECT A TYPICAL SUMMERTIME
PATTERN OF PM TSTORMS FAVORING THE MTNS WITH LESS OUT OVER THE
PIEDMONT. SOME UPPER ENERGY WILL BE APPROACHING FROM THE NW LATE
THURS...BUT MOST EFFECTS SHOULD HOLD OFF UNTIL AFTER THE END OF THE
CURRENT FORECAST.

MONDAY HIGH TEMPS WILL BE AROUND 7 DEGREES BELOW NORMAL THEN REBOUND
TO NEAR NORMAL WED AND THURS.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AT KCLT...LIGHT TO MODERATE RAIN SHIELD WILL CONTINUE TO COME AND GO
AT CLT THIS MORNING WITH CONTINUED LOW OF CIGS MVFR...POSSIBLY
IFR... THROUGH 16Z. NOT MUCH IMPROVEMENT THIS AFTERNOON AS SFC
HEATING WILL BE SLOW. THE TAF REMAINS PESSIMISTIC WITH MVFR CIGS
EXPECTED MOST OF THE DAY THEN A DROP BACK IFR LATE ARND 03Z. THUNDER
CHANCES REMAIN HIGH ENOUGH FOR PROB30 MENTION AFT 21Z.

ELSEWHERE...A MIXED BAG OF CIGS/VSBY THIS MORNING DEPENDING ON THE
INTENSITY AND LOCATION OF RAINFALL. ALL SITES SHOULD REMAIN LOW
MVFR...IF NOT IFR...THIS MORNING MAINLY FOR CIGS. KAND SHOULD REMAIN
VFR THIS MORNING AND INTO THE AFTERNOON AS DRIER AIR MIXES IN FROM
THE WEST. OTHER SITES WILL LIKELY TEMPO MVFR/VFR THROUGH THE
DAY...WITH LOWERING CIGS TO IFR LATE IN THE TAF PERIOD. THUNDER
CHANCES REMAIN HIGH ENOUGH FOR VCTS MENTION ALL SITES THIS
AFTERNOON.

OUTLOOK...UNSETTLED WEATHER WITH ENHANCED PRECIPITATION CHANCES
ALONG WITH MORNING FOG/STRATUS ARE EXPECTED THROUGH THE WEEKEND.

CONFIDENCE TABLE...

            12-18Z        18-24Z        00-06Z        06-12Z
KCLT       HIGH  83%     HIGH  80%     MED   62%     HIGH  91%
KGSP       MED   74%     MED   79%     MED   68%     MED   61%
KAVL       MED   79%     MED   67%     MED   77%     HIGH  81%
KHKY       HIGH  83%     HIGH  88%     MED   78%     HIGH  83%
KGMU       MED   78%     MED   78%     MED   67%     LOW   48%
KAND       MED   69%     MED   60%     MED   60%     LOW   58%

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...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR GAZ010-017-018-026-
     028-029.
NC...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR NCZ033-048>053-058-
     059-062>065-501>510.
SC...FLASH FLOOD WATCH UNTIL NOON EDT TODAY FOR SCZ001>007-010>012-
     019.

&&

$$
SYNOPSIS...JPT
NEAR TERM...JAT/SBK
SHORT TERM...JPT
LONG TERM...DEO
AVIATION...SBK





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