Area Forecast Discussion
Issued by NWS Greer, SC

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000
FXUS62 KGSP 030736
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
336 AM EDT MON AUG 3 2015

.SYNOPSIS...
DRY HIGH PRESSURE WILL REMAIN IN PLACE ACROSS THE AREA TODAY. LOW
LEVEL MOISTURE WILL GRADUALLY RETURN THROUGH THE WORK WEEK AS A COLD
FRONT APPROACHES FROM THE AREA FROM THE NORTHWEST.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 240 AM...UPPER TROF REMAINS OVER THE ERN CONUS TODAY...THEN
BEGINS TO LIFT TONIGHT AS A WEAK SHORTWAVE MOVES EAST OF THE AREA.
AT THE SFC...WEAK HIGH PRESSURE REMAINS OVER THE AREA AS A LOW
PRESSURE CENTER RIDES UP THE EAST COAST ALONG A LEFTOVER FRONTAL
BOUNDARY. FINALLY A COLD FRONT WILL DROP SOUTH TOWARD THE AREA LATE
TONIGHT. DEW POINTS ARE MUCH HIGHER ACROSS THE AREA THIS MORNING AS
A SEABREEZE BOUNDARY HAS MOVED NORTH ACROSS THE CWFA BRINGING IN THE
BETTER LOW LEVEL MOISTURE. DESPITE THE HIGHER START...STILL EXPECT
DEW POINTS TO MIX OUT...ALTHOUGH NOT TO THE EXTREME OF THE PAST FEW
DAYS. THE NAM AND CAM GUIDANCE SHOW CONVECTION DEVELOPING ACROSS THE
AREA TODAY. HOWEVER...THE GFS AND ECMWF CONTINUE TO SHOW A DRY FCST.
GIVEN THE RECENT TRENDS WITH THE WETTER GUIDANCE SHOWING A STRONG
WET BIAS...AND SOME DEW POINT MIXING...WILL KEEP WITH THE CURRENT
DRY FCST FOR NOW. CANNOT RULE OUT SOME LINGERING CONVECTION MOVING
INTO THE NRN TIER FROM MCS ACTIVITY AHEAD OF THE FRONT. HOWEVER...
WILL KEEP POP DRY THEN AS WELL. TEMPS WILL BE UP TO 5 DEGREES ABOVE
NORMAL TODAY AND TONIGHT.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AT 230 AM EDT MONDAY...ON TUESDAY MORNING ZONAL UPPER LEVEL FLOW
WILL EXIST ACROSS THE SOUTHERN TIER OF STATES...TO THE SOUTH OF AN
UPPER LOW OVER JAMES BAY AND A RIDGE OVER THE NORTHERN ROCKIES. THIS
PATTERN PERSISTS INTO WEDNESDAY NIGHT.

AT THE SURFACE...A WEAKENING STATIONARY FRONT WILL BE NEAR THE
CAROLINA AND GA COASTS ON TUESDAY MORNING...WHILE A COLD FRONT MOVES
SOUTH OF THE OH RIVER VALLEY. THE COLD FRONT REACHES THE NC
MOUNTAINS TUESDAY EVENING....MOVING INTO THE UPSTATE SC ON
WEDNESDAY. THE BOUNDARY THEN RETURNS NORTH AS A WARM FRONT ON
WEDNESDAY NIGHT...REACHES VA BY THURSDAY MORNING.

PRECIPITATION CHANCES WILL INCREASE AS MOISTURE SPREAD EAST ALONG
THE FRONT FROM THURSDAY NIGHT INTO WEDNESDAY NIGHT. INSTABILITY WILL
ACTUALLY BE GREATER ON TUESDAY BEFORE THE FRONT ARRIVES AND
MOISTURE INCREASES. TEMPERATURES WILL RUN ABOVE NORMAL AS COLD
ADVECTION NEVER REALLY SETS UP WITH FRONT RETREATING.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AT 230 AM EDT MONDAY...ON THURSDAY NEARLY ZONAL UPPER LEVEL FLOW
WILL BE OVER THE CONTINENTAL USA...WITH SHORTWAVE ENERGY CROSSING
THE MS RIVER VALLEY. THE SHORTWAVE WILL CROSS THE SOUTHERN
APPALACHIANS ON FRIDAY. THE UPPER PATTER AMPLIFIES BY SATURDAY...
WITH A TROUGH OVER THE PLAINS...AND A TROUGH OVER THE EAST. BY
SUNDAY THE PATTERN STARTS TO DEAMPLIFY...AND THE RIDGE EXPANDS
EASTWARD ACROSS THE GULF STATES. MEANWHILE...A WEAK UPPER TROUGH
REMAINS ALONG THE EAST COAST.

AT THE SURFACE...ON THURSDAY A STATIONARY FRONT WILL EXTEND FROM THE
VA CAPES TO THE OH RIVER VALLEY...WHILE ATLANTIC SURFACE RIDGING
EXTEND ACROSS FL TO THE GULF OF MEXICO. THE BOUNDARY DROPS SOUTH AS A
COLD FRONT ON FRIDAY...REACHING WESTERN NC ON FRIDAY NIGHT...AND
CROSSING UPSTATE SC AND NE GA ON SATURDAY. THIS FRONT REACHES S GA
AND THE SC COAST ON SUNDAY COOL HIGH PRESSURE NOSES DOWN THE EASTERN
SEABOARD BEHIND THIS FRONT.

ONLY MODEST INSTABILITY WILL BE PRESENT AHEAD OF THE FRONT.
PRECIPITATION CHANCES AND AMOUNTS SHOULD DIMINISH AS THE FRONT DROPS
SOUTH OF THE AREA. TEMPERATURES WIL EXPERIENCE A DOWNWARD TREND AS
THE FRONT MOVES THROUGH AND HEIGHTS FALL ALOFT.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
AT KCLT...VFR MOST LIKELY WILL PREVAIL THRU 06Z TUE. AS AN UPPER
TROF DIGS TOWARD THE SOUTH ATLANTIC COAST THIS MORNING...A WEAK SFC
LOW WILL SPIN UP OVER SRN GA. NAM AND SOME OF THE OTHER WRF BASED
GUIDANCE ADVECT STALLED FRONTAL BOUNDARY NWD FROM SC...AND BRING
MVFR STRATUS OVER THE FIELD IN THE MRNG. IT CURRENTLY APPEARS THESE
MODELS ARE OVERDOING THIS. HOWEVER SUCH A DECK WILL LIKELY BE NOT
TOO FAR AWAY. TO HINT AT THE POTENTIAL A SCT MVFR LEVEL DECK WAS
MENTIONED NEAR DAYBREAK. WINDS START OUT SSE THEN GO SW FOR THE
AFTERNOON...BACK TO SSE FOR THE EVENING. LOW VFR CU SHOULD BREAK OUT
BY AFTN....BUT WILL LIKELY START BEFORE NOON THEN RISE THRU THE DAY.
HIGH BASED CU CONTINUE INTO THE EVENING.

ELSEWHERE...SOME RESTRICTED VSBYS ARE EXPECTED BRIEFLY NEAR DAYBREAK
AT KAVL...WITH MOISTURE IMPROVING SOMEWHAT COMPARED TO RECENT
MORNINGS. ENOUGH MOISTURE IS ALSO EXPECTED TO ADVECT INTO THE LOWER
PIEDMONT FOR SOME PATCHY FOG AT KAND. OTHERWISE VFR THRU THE PERIOD
WITH FAIR WEATHER CU DEVELOPING EARLY ACROSS THE AREA. EXCEPT FOR
NNW WINDS AT KAVL THRU THE PERIOD...VERY LIGHT S TO SW SELY WINDS
WILL PREVAIL THRU THE PERIOD.

OUTLOOK...GRADUALLY INCREASING PRECIPITATION/RESTRICTION CHANCES
THROUGH MID WEEK AS MOIST SOUTHERLY FLOW RETURNS AHEAD OF THE NEXT
COLD FRONT.

CONFIDENCE TABLE...

            07-13Z        13-19Z        19-01Z        01-06Z
KCLT       HIGH  98%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH  96%     HIGH 100%     HIGH 100%     HIGH 100%
KHKY       HIGH  98%     HIGH 100%     HIGH 100%     HIGH 100%
KGMU       HIGH  98%     HIGH  96%     HIGH 100%     HIGH 100%
KAND       HIGH  91%     HIGH  97%     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...JAT
NEAR TERM...RWH
SHORT TERM...JAT
LONG TERM...JAT
AVIATION...RWH



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