Area Forecast Discussion
Issued by NWS Greer, SC

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000
FXUS62 KGSP 061439
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1039 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. A BROAD UPPER RIDGE WILL
STRENGTHEN AND MIGRATE OVER THE SOUTHEAST THROUGH THE REMAINDER OF
THE WEEK AND INTO THE WEEKEND.  AS A RESULT...SHOWER AND
THUNDERSTORM CHANCE WILL BECOME INCREASINGLY DIURNAL IN NATURE.
TEMPERATURES ARE ALSO EXPECTED TO MODERATE TO ABOVE NORMAL LEVELS.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM...RADAR SHOWS SOME DISSIPATING LIGHT SHOWERS OVER THE
NORTHERN NC PIEDMONT. THE FOCUS FOR ADDITIONAL PRECIP WILL SHIFT TO
THIS AFTERNOON. THE REMNANTS OF THE UPPER TROUGH IS STILL LINGERING
ACROSS THE WESTERN CAROLINAS INTO NE GA. SATELLITE PICS SHOW QUITE A
BIT OF CLOUDINESS FROM FAR WESTERN NC INTO GA APPARENTLY ASSOCIATED
WITH A VORT MAX. THE 12Z NAM LIFTS THIS FEATURE SLOWLY E-NE. THE NAM
IS THE MOST BULLISH IN TRIGGERING DEEP CONVECTION ALONG THE
ESCARPMENT EARLY THIS AFTERNOON AND THEN DEVELOPING MORE SCT TSRA
OVER EASTERN SECTIONS THIS EVENING. THE LATEST CAMS ARE MUCH MORE
MUTED. USED A BLEND OF THE LATEST CONSSHORT AND NAM ND5 POPS. THIS
RESULTS IN CHANCE POPS ALONG THE ESCAPRMENT THIS AFTERNOON AND ALSO
OVER PARTS OF THE I-77 CORRIDOR THIS EVENING. OTHERWISE...ANY
CONVECTION WILL BE ISOLATED IN NATURE. ALSO TRENDED TEMPS/DEWPOINTS
AND SKY TO LATEST CONSHORT DATA.

AS OF 645 AM...THE UPPER TROUGH THAT HAS LINGERED OVER THE CWFA THE
PAST COUPLE OF DAYS IS LOSING INFLUENCE AS IT DRIFTS NEWD. THE BEST
DPVA IS ALREADY OFF TO OUR NORTHEAST. A BAND OF LIGHT SHOWERS
HOWEVER ILL CONTINUE TO ROTATE ACRS THE NRN MTN/FOOTHILL ZONES OVER
THE NEXT COUPLE OF HRS. THESE WILL PROBABLY BE NO MORE THAN
SPRINKLES IN MANY AREAS. PATCHY FOG AND LOW CLOUDS WILL BE SEEN OVER
THE PIEDMONT...BUT THESE SHOULD MIX OUT BY 9 A.M. OR SO.

CYCLONIC MID-UPPER FLOW WILL REMAIN OVERHEAD THRU MOST OF THE DAY.
THOUGH EMBEDDED VORTICES MIGHT PROVIDE MESOSCALE ENHANCEMENT TO
LIFT...THE UPPER PATTERN IS EXPECTED TO HAVE LITTLE IMPACT ON POPS
EXCEPT PERHAPS TO ALLOW THE LIGHT SHOWERS OVER THE NRN CWFA AT
DAYBREAK TO CONTINUE SPREADING EAST THRU THE MRNG. MAJOR MODELS
INCLUDING THE CONVECTION ALLOWING SPC AND NSSL WRF RUNS MAINLY KICK
OFF ACTIVITY ALONG THE SRN END OF THE BLUE RIDGE AT
MIDDAY...PROPAGATING IT EWD AND FEATURING THE BEST COVERAGE OVER THE
PIEDMONT BY MID-AFTN. SOME DIFFERENCES CONTINUE TO BE SEEN BETWEEN
NAM AND GFS IN TERMS OF INSTABILITY...MORESO THAN USUAL. GFS SHOWS
POORER LAPSE RATES PERHAPS ON ACCOUNT OF SUBSIDENCE IN THE WAKE OF
THE TROUGH. NONETHELESS BOTH MODELS SUPPORT SCATTERED ACTIVITY.
TSTMS ARE EXPECTED TO REMAIN MORE ISOLATED THAN SHOWERS WITH
BUOYANCY IN QUESTION. PROFILES WILL BE QUITE A BIT DRIER IN THE
UPPER LEVELS WHICH MIGHT ALLOW TSTMS TO PRODUCE ROBUST
OUTFLOWS...PARTICULARLY IF THE HIGHER NAM CAPES VERIFY. HOWEVER I
WILL NOT VENTURE TO SAY THAT DAMAGING WINDS CAN BE EXPECTED. MAX
TEMPS WILL BE CLOSE TO NORMAL...MAYBE A DEGREE OR TWO BELOW.

TONIGHT POPS DIMINISH WITH NOCTURNAL STABILIZATION AND CONTINUED
DEPARTURE OF THE TROUGH. HOWEVER WITH WARM ADVECTION RAMPING UP OVER
THE TENN VALLEY IN SW FLOW AHEAD OF THE MIDWEST TROUGH...I KEPT AN
ISOLD SHOWER MENTION AND MCLDY SKIES OVER THE MTNS. MIN TEMPS WILL
BE SIMILAR TO THOSE THIS MORNING...ABOUT NORMAL.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM EDT MONDAY...THE SHORT TERM FCST PERIOD INITIALIZES
TUESDAY MORNING AMIDST BUILDING UPPER RIDGING OVER THE WESTERN
ATLANTIC...WHILE A LOW AMPLITUDE TROF DIGS ACROSS THE UPPER MIDWEST
AND GREAT LAKES STATES.  AT THE SURFACE...A COLD FRONT TIED TO SAID
UPPER TROFFING WILL EXTENDED FROM THE UPPER PENINSULA OF
MICHIGAN...SOUTHWARD THROUGH THE MID MISSISSIPPI RIVER VALLEY INTO
THE SOUTHERN PLAINS.  FURTHER EAST...BERMUDA HIGH PRESSURE WILL
STRENGTHEN LEADING TO IMPROVING/PREVAILING SOUTHERLY FLOW OVER THE
SOUTHEAST.  IN RESPONSE...MODELS INDICATE MODEST DESTABILIZATION ON
TUESDAY WITH UPWARDS OF 1K-2K SBCAPE ACROSS THE AREA.  THUS...THE
FCST FOR TUESDAY WILL FEATURE DIURNALLY FAVORED POPS WITH MID/HIGH
CHANCE POPS OVER THE MTNS WHERE UPPER HEIGHTS ARE LOWEST.  POPS OVER
THE LOW TERRAIN REMAIN AT SLIGHT CHANCE LEVELS DUE TO WEAK
SUBSIDENCE...DESPITE SOME FOCUSING POSSIBLE ALONG PIEDMONT
TROFFING.  DUE TO WEAK SHEAR...ANY STORMS THAT DO DEVELOP WILL
LIKELY BE PULSE IN NATURE AND COULD REACH STRONG/SEVERE LIMITS WITH
DAMAGING WINDS AND HAIL BEING THE PRIMARY THREATS THANKS TO INVERTED
V PROFILES AMONGST DEEP MIXED LAYER.  TEMPERATURES ON TUESDAY WILL
RETURN TO CLIMO LEVELS.

POPS WILL TAPER TO NON MENTIONABLE LEVELS OVERNIGHT INTO WEDNESDAY
MORNING WITH HEATING LOSS.  MEANWHILE...THE ABOVE MENTIONED UPPER
RIDGE WILL ELONGATE AND BEGIN A MULTIDAY JOURNEY OF WESTWARD
RETROGRESSION WHILE THE COLD FRONT SLIDES INTO THE OH VALLEY...ALL
THE WHILE REMAINING NORTH OF THE CWFA.  IN RESPONSE...TEMPERATURES WILL
FINALLY RETURN TO ABOVE CLIMO LEVELS ON WEDNESDAY AS HEIGHTS RISE
ALOFT.  PROFILES WILL ONCE AGAIN EXHIBIT A DEEP/DRY MIXED
LAYER...AND WEAK SHEAR LEADING TO PULSE STORMS WITH MICROBURSTS/HAIL
BEING THE PRIMARY THREATS.  AS FOR THE FCST...POPS REMAIN AT CHANCE
LEVELS OVER THE HIGH TERRAIN WITH SLIGHT CHANCES FEATURED OVER THE
PIEDMONT REGIONS.  OVERALL...EXPECTING COVERAGE TO BE SOMEWHAT
DIMINISHED ON WEDNESDAY AS SUBSIDENCE IMPROVES LEADING TO AT LEAST
MODEST CAPPING.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 330 AM EDT MONDAY...THE MEDIUM RANGE FCST PERIOD INITIALIZES
THURSDAY MORNING AS A 593DM H5 RIDGE CONTINUES TO SLOWLY RETROGRADE
WESTWARD...WHILE A BERMUDA HIGH PREVAILS AT THE SURFACE.  THE
PATTERN WILL SLOWLY EVOLVE THROUGH THE MEDIUM RANGE WHICH IS
HIGHLIGHTED BY THE UPPER RIDGE CENTER SHIFTING WESTWARD.
MEANWHILE...A SERIES OF UPPER IMPULSES WILL SLIDE ATOP THE RIDGE
AXIS AMONGST THE QUASIZONAL FLOW ACROSS THE OHIO AND MID MISSISSIPPI
RIVER VALLEYS.  THIS WILL LIKELY BE OF NO CONSEQUENCE TO NORTHEAST GA
AND THE WESTERN CAROLINAS THROUGH AT LEAST THE START OF THE
WEEKEND.  THUS...THE FCST FEATURES ONLY DIURNALLY FAVORED SHOWERS
AND THUNDERSTORMS THURSDAY/FRIDAY WITH POPS AROUND OR JUST BELOW
CLIMO LEVELS DUE TO DEEP LAYER SUBSIDENCE.

PRECIPITATION CHANCES WILL SLOWLY INCREASE THROUGH THE WEEKEND AND
INTO THE START OF NEXT WEEK AS THE UPPER RIDGE CENTER SHIFTS FURTHER
WEST PLACING THE SOUTHERN APPS ON THE DESCENDING BRANCH.  ON TOP OF
INCREASING DIURNAL CHANCES DUE TO WEAKENING SUBSIDENCE...THIS
PATTERN WILL ALSO LEND ITSELF TO INCREASED EVENING/OVERNIGHT MCS
PROPAGATION.  THUS...POPS WILL RETURN TO CLIMO LEVELS SATURDAY AND
SUNDAY.  TEMPERATURES THROUGH THE MEDIUM RANGE ARE EXPECTED TO
CONTINUALLY CLIMB TO AROUND 3-5 DEGREES ABOVE CLIMO BY
SUNDAY...WHICH COMBINED WITH UPPER 60S DEWPOINTS COULD YIELD
INCREASED HEAT THREATS.

&&

.AVIATION /15Z 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...WHICH WILL THIN AND
MOVE NEWD THRU THE MRNG. HOWEVER SPOTTY IFR CIGS AND FOG ARE BEING
REPORTED NORTH AND SOUTH OF KCLT. IT IS NOT OUT OF THE QUESTION THAT
THESE WILL AFFECT THE FIELD...BUT MORE LIKELY THAN NOT THEY WILL
LIFT OUT FAIRLY QUICKLY. OTHERWISE...NO RESTRICTIONS EXPECTED THIS
MRNG. DURING THE DAY...FLOW WILL CONTINUE TO BE GENERALLY SW EAST OF
THE MTNS...NW OVER KAVL. DIURNALLY DRIVEN SCT SHRA AND A FEW TSRA
ARE EXPECTED TO FORM INVOF THE BLUE RIDGE ESCARPMENT AND PROPAGATE
EWD THRU THE AFTN. HAVE USED VCSH AND/OR VCTS AS NEEDED TO HIGHLIGHT
THIS LOW CHANCE. CAN/T RULE OUT A TS AFFECTING ANY SITE
HOWEVER...WITH BIGGEST IMPACT LIKELY LTNG AND GUSTY WINDS.
TONIGHT...FLOW BECOMES RATHER LIGHT...THOUGH IT APPEARS MUCH OF THE
AREA WILL REMAIN TOO DRY FOR FOG OR LOW CIGS TO DEVELOP...EXCEPT IN
THE MTN VALLEYS. VFR EXPECTED EVERYWHERE BUT KAVL.

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...

            14-20Z        20-02Z        02-08Z        08-12Z
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  87%
KHKY       HIGH 100%     HIGH 100%     HIGH 100%     MED   74%
KGMU       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAND       HIGH  90%     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/WIMBERLEY
NEAR TERM...LG/WIMBERLEY
SHORT TERM...CDG
LONG TERM...CDG
AVIATION...WIMBERLEY



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