Area Forecast Discussion
Issued by NWS Greer, SC

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000
FXUS62 KGSP 012035
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
435 PM EDT SAT AUG 1 2015

.SYNOPSIS...
DRY HIGH PRESSURE WILL REMAIN IN PLACE ACROSS THE AREA THROUGH THE
WEEKEND. LOW LEVEL MOISTURE WILL GRADUALLY RETURN NEXT WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH.

&&

.NEAR TERM /THROUGH SUNDAY/...
AS OF 430 PM EDT SATURDAY...MOSTLY SUNNY SKIES PREVAIL WITH ONLY A
FEW FAIR WX CUMULUS SPREAD ABOUT THE REGION.  WINDS REMAIN GENERALLY
LIGHT AND NORTHERLY WITH SOME LOW END GUSTS OCCURRING IN THE MTN
VALLEYS DUE TO CHANNELING.  TWEAKED TEMPERATURES/DEWPOINTS ALONG
WITH SKY IN THE IMMEDIATE NEAR TERM AND LEFT THE REMAINDER OF THE
FCST AS IT WAS FOR THIS UPDATE.

PREVIOUS DISCUSSION...

AS OF 215 PM...NOT MUCH CHANGE IN THE UPPER PATTERN THRU THE NEAR
TERM...WITH A PERSISTENT TROF OVER THE EASTERN CONUS AND LARGE RIDGE
ACRS THE WEST. AN UNUSUALLY DRY AIR MASS FOR THIS TIME OF YEAR HAS
SETTLED IN ACRS THE AREA. THIS SHUD KEEP POPS AT A MINIMUM WITH JUST
A FEW CLOUDS HERE AND THERE. TEMPS WILL NEAR OR EVEN A DEG OR TWO
BELOW NORMAL IN SPOTS TONIGHT.

SUNDAY...MODELS HINT AT SOME RETURN OF LLVL MOISTURE INTO THE
AREA...AS SFC HIGH PRES BUILDS INTO THE CENTRAL
APPALACHIANS...ALLOWING FOR A LIGHT EASTERLY FLOW ATOP THE CWFA. THE
NAM IS MOST BULLISH ON THIS...AND HAS SOME CONVECTIVE RESPONSE IN
THE NC MTNS. THIS AND THE SREF ARE ABOUT THE ONLY MODELS THAT SHOW
THIS. I WILL KEEP A SLGT CHC POP FOR THE TYPICAL CENTRAL AND SW NC
MTN PEAKS THAT OFTEN STILL TRIGGER CONVECTION IN SPITE OF DRY
GUIDANCE. TEMPS WILL RISE TO A CATEGORY OR TWO ABOVE NORMAL AGAIN
WITH MOSTLY SUNNY SKIES EXPECTED.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
AS OF 215 PM SATURDAY...IT LOOKS LIKE OUR QUIET WEATHER WILL REMAIN
AT LEAST INTO MONDAY...THEREAFTER WE CAN EXPECT A RETURN TO MORE
DIURNAL THUNDERSTORM CHANCES AS LOW LEVEL MOISTURE STARTS TO
IMPROVE. THE DRY WEATHER CONTINUES ON SUNDAY NIGHT AND MONDAY AS WE
SHOULD STILL BE AT THE BOTTOM OF AN UPPER TROF WITH A WNW FLOW
ALOFT. DEWPOINT WILL PROBABLY MIX OUT AGAIN ON MONDAY AFTERNOON...
DOWN INTO THE 50S IN MANY PLACES E OF THE MTNS...WHICH WOULD CUT
BACK ON THE POTENTIAL FOR POSITIVE BUOYANCY. THE NAM ACTUALLY
DEVELOPS A MOISTURE BOUNDARY NEAR THE EASTERN FRINGE OF FCST AREA...
WHICH THE MODEL ACTS UPON WITH SHOWER DEVELOPMENT. FOR NOW...THIS
WAS DISCOUNTED AS BEING AN OUTLIER. THE FCST WAS KEPT DRY OVER THE
PIEDMONT...THRU TUESDAY MORNING. SOME CHANGES WILL BEGIN ON TUESDAY
AS A SHORT WAVE TO THE WEST BEGINS TO FLATTEN AND LIFT THE TROF.
THIS ALLOWS MOISTURE TO INCREASE AS A SURFACE BOUNDARY STARTS TO SAG
DOWN INTO THE REGION FROM THE N. THE INCREASED BUOYANCY COMBINED
WITH THE POTENTIAL TRIGGER SUGGESTS A BETTER CHC FOR AFTERNOON
STORMS...AT LEAST OVER THE NC PART OF THE FCST AREA...SO PRECIP
CHANCES WERE NUDGED A BIT ABOVE GUIDANCE. TEMPS WILL CLIMB A BIT
EACH DAY...BUT RH WILL BE LOW ENOUGH SO AS TO KEEP HEAT INDEX BELOW
ADVISORY CRITERIA.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 215 PM SATURDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
WEDNESDAY WITH BROAD UPPER TROFFING CENTERED OVER THE GREAT LAKES AND
PERSISTENT UPPER RIDGING OVER THE WESTERN CONUS. OVER THE NEXT COUPLE
OF DAYS...THE PATTERN IS EXPECTED TO DEAMPLIFY TO SOME DEGREE AS THE
UPPER TROF LIFTS TO THE NE AND ANOTHER NORTHERN STREAM UPPER TROF HELPS
TO FLATTEN THE RIDGE OVER THE WEST. AT THE SAME TIME...A SERIES OF FAIRLY
POTENT LOOKING EMBEDDED UPPER SHORTWAVES APPROACH THE FCST AREA FROM
THE WEST AND NW. AT THE SFC...THE SUBTROPICAL BERMUDA HIGH WILL MAINTAIN
ITS INFLUENCE OVER THE SE REGION THRU MOST OF THE PERIOD WITH GENERALLY
LIGHT SLY FLOW. AS HAS BEEN THE CASE OVER THE PAST COUPLE OF WEEKS...THE
LONG RANGE MODELS DO NOT APPEAR VERY CONSISTENT WITH THE EVOLUTION OF
THE SFC PATTERN FOR MOST OF THE MEDIUM RANGE. THEY ATTEMPT TO SPIN UP
SOME SORT OF LOW ON THRUS AND MOVE IT OFFSHORE BY FRI AND THEN DEVELOP
ANOTHER LOW JUST TO OUR WEST ON FRI AND END WITH DRIER CONDITIONS
FOR SAT. AT THIS POINT...IT IS DIFFICULT TO PLACE MUCH CONFIDENCE ON
ANY SPECIFIC MODEL SOLUTION SO I OPTED FOR AN OVERALL BLEND. POPS INCREASE
FOR THURS AND FRI AND TAPER BACK AGAIN ON SAT BUT STILL REMAIN AT SLIGHT
TO SOLID CHANCE. TEMPS START OUT ABOVE NORMAL AND THEN COOL A FEW DEGREES
TOWARDS THE END OF THE WEEK.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
AT KCLT...VFR. THERE IS JUST ENUF MOISTURE FOR A FEW CUMULUS OUT
THERE WITH BASES AROUND 7000 FT. OTHERWISE...THE MAIN CONCERN WILL
BE WINDS (AND THAT SHUD NOT BE MUCH). WINDS SHUD FAVOR A N DIRECTION
THRU THE PERIOD (MAINLY NW THIS EVENING...THEN NE SUNDAY MORNING).
THEY WILL BE GENERALLY 5 KT OR LESS TONIGHT...THEN INCREASE AGAIN
AROUND DAYBREAK TO AROUND 8-10 KTS.

ELSEWHERE...VFR. UNUSUALLY DRY AIR FOR THIS TIME OF YEAR HAS SETTLED
IN ACRS THE REGION. WINDS HAVE BEEN OCCASIONALLY GUSTY SO FAR
TODAY...AND GUST POTENTIAL SHUD GRADUALLY END LATE AFTN/EARLY EVE. N
TO NE WIND WILL INCREASE AGAIN AROUND DAYBREAK SUNDAY...WITH A FEW
LOW-END GUSTS POSSIBLE MID MORNING WHEN MIXING STARTS TO DEEPEN.

OUTLOOK...FLIGHT CONDITIONS WILL REMAIN RESTRICTION FREE THROUGH THE
WEEKEND AHEAD OF GRADUALLY INCREASING PRECIPITATION/RESTRICTION
CHANCES THROUGH MID WEEK AS MOIST SOUTHERLY FLOW RETURNS.

CONFIDENCE TABLE...

            20-02Z        02-08Z        08-14Z        14-18Z
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 100%
KHKY       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGMU       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAND       HIGH 100%     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...JPT
NEAR TERM...ARK/CDG
SHORT TERM...PM
LONG TERM...JPT
AVIATION...ARK



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