Area Forecast Discussion
Issued by NWS Greer, SC

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS62 KGSP 280536
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
136 AM EDT SUN JUN 28 2015

.SYNOPSIS...
A COLD FRONT WILL PUSH OUT OF THE REGION EARLY SUNDAY BRINGING
COOLER AND DRIER CONDITIONS TO START THE NEW  WEEK. ANOTHER FRONT
WILL APPROACH THE REGION BY MID-WEEK AND WEAKEN ACROSS THE
MOUNTAINS. THEREAFTER THE REGION WILL STAY IN A WARM AND MOIST
ENVIRONMENT WHICH WILL SUPPORT ISOLATED TO SCATTERED SHOWER AND
THUNDERSTORM COVERAGE TYPICAL OF EARLY JULY.

&&

.NEAR TERM /THROUGH TODAY/...
1015 PM UPDATE...COLD FRONT NOW IS ORIENTED ALONG THE ERN SLOPES OF
THE APPALACHIANS. SOME LIGHT BANDS OF PRECIP CONTINUE AHEAD OF IT
BUT THIS WILL NOT AMOUNT TO MUCH...AND CONVECTION IS UNLIKELY TO
GET GOING AGAIN...WITH MOST OF THE AREA AHEAD OF THE FRONT HAVING
ALREADY BEEN WORKED OVER. SETTLED CONDITIONS WILL RETURN IN THE
WAKE OF THE FRONT. SOME GUSTY WINDS COULD OCCUR OVER THE HIGH
TERRAIN IN COLD ADVECTION NEAR DAYBREAK...BUT MAJOR ISSUES ARE NOT
ANTICIPATED. DEWPOINTS WILL AT LEAST BEGIN TO DROP OFF WITH THE
INCOMING AIRMASS TONIGHT. THERE IS SOME CHANCE THEY WILL NOT FALL
FAST ENOUGH TO OUTPACE COOLING TEMPS...AND SOME FOG COULD
DEVELOP...PARTICULARLY WHERE SOILS ARE WET FROM AFTN RAINS.
HOWEVER BASED ON THE LATEST GUIDANCE IT APPEARS THE DEWPOINTS WILL
LIKELY DROP FASTER THAN TEMPS...NOT ONLY BECAUSE OF ABUNDANT MID-
HIGH CLOUD COVER STILL OVERHEAD.

AS OF 230 PM SATURDAY...SUNDAY WILL BE ABOUT AS FINE A LATE-JUNE DAY
AS ONE SEES IN THE SOUTHEAST...MAINLY OWING TO THE MUCH DRIER AIR.
IN FACT...DEWPOINTS WILL LIKELY MIX OUT TO THE LOWER/MID 50S IN MANY
AREAS OUTSIDE THE MTNS...AND POSSIBLY THE 40S ACROSS THE HIGHER
TERRAIN. ALTHOUGH TEMPS ARE EXPECTED TO ONLY BE A CATEGORY OR SO
BELOW CLIMO... CONSIDERING HOW HOT IT/S BEEN OVER THE PAST TWO
WEEKS...IT WILL PROBABLY FEEL LIKE AUTUMN TO MOST FOLKS.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY/...
AT 230 PM EDT SATURDAY... OVERALL BIG PICTURE CONTINUES TO INDICATE
AN ANOMALOUS UPPER AIR PATTERN...WITH HIGH AMPLITUDE RIDGING ACROSS
THE WESTERN CONUS AND TROFFING IN THE EAST.

DURING THIS PART OF THE FORECAST CYCLE WE SHOULD MAINTAIN A NWLY TO
WESTERLY FLOW ALOFT. A WEAK BUBBLE OF SURFACE HIGH PRESSURE WILL
MIGRATE THROUGH OUR FORECAST AREA SUNDAY NIGHT AND MONDAY WITH QUIET
WEATHER CONDITIONS ON TAP.

ENERGY DROPPING SEWD MONDAY NIGHT...FROM THE UPPER MIDWEST AND
WESTERN GREAT LAKES...WILL REACH THE NC MOUNTAINS. DPVA COUPLED WITH
BACKING SURFACE-H85 FLOW (AN INCREASE IN MOISTURE)...WILL LEAD TO A
SMALL CHANCE OF SHOWERS OR THUNDERSTORMS. THIS SHOULD BE NOTED IN
THE WEE HOURS LATE MONDAY NIGHT/TUESDAY BEFORE DAYBREAK.

A TEMPORARY BACKING FLOW WILL THEN SET-UP THROUGHOUT OUR FA TUESDAY.
A SECONDARY COLD FRONT...ASSOCIATED WITH THE UPPER LEVEL ENERGY...
WILL EITHER WASH OUT OR BECOME ABSORBED IN A LEE TROUGH TYPE
CONFIGURATION. NEVERTHELESS...MOISTURE RAMPING UP...A SHOT OF ENERGY
SWIFTLY MOVING THROUGH THE REGION AND A WARM AIR ADVECTION PATTERN
SETTLING IN...WILL LEAD TO CHANCE POPS OVER OUR REGION.

RUNNING VARIOUS TOOLS FOR STABILITY INDICES SUGGEST THUNDER MENTION
OVER ALL OF OUR REGION DURING THIS EPISODE.

IN THE TEMPERATURE DEPARTMENT...H85 THERMAL PROFILE AND THICKNESS
LEVELS...ALL INDICATE A SLOW UPWARD TREND IN THE MAXIMUM AND MINIMUM
TEMPERATURES...AS WE MOVE OUT IN TIME EARLY IN THE NEW WORK WEEK.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AT 300 PM EDT SATURDAY...THE MEDIUM-RANGE PERIOD BEGINS ON TUESDAY
NIGHT WITH A DEEP MID-LEVEL RIDGE CENTERED OVER THE INTERMOUNTAIN
WEST AND CORRESPONDING MID-LEVEL TROUGH EXTENDING FROM THE HUDSON
BAY TO THE GULF COAST.  HOWEVER...DURING THE WEEK THE PATTERN SLOWLY
EVOLVES AS THE RIDGE CENTER RETROGRADES TOWARDS CA/NV WHILE THE
TROUGH AXIS SHIFTS WEST TOWARDS THE MS RIVER VALLEY.  MEANWHILE THE
ATLANTIC SUBTROPICAL RIDGE DEEPENS AND EXPANDS WEST TOWARDS THE EAST
COAST...PLACING THE LOCAL AREA IN WSW FLOW ALOFT BY THE END OF THE
PERIOD ON SUNDAY MORNING.

EMBEDDED WITHIN THE UPPER-LEVEL FLOW TUESDAY NIGHT IS A SHORTWAVE
WHICH WILL PIVOT AROUND THE LOWER GREAT LAKES AND THROUGH NEW
ENGLAND BY WEDNESDAY MORNING. AN ASSOCIATED WEAK COLD FRONT
APPROACHES FROM THE TN RIVER VALLEY INCREASING COVERAGE OF SHOWERS
AND THUNDERSTORMS THROUGH WEDNESDAY MORNING. THE FRONT DISSIPATES
OVER THE CAROLINAS ON WEDNESDAY.  THEREAFTER...AT LEAST A HALF DOZEN
NOTABLE SHORTWAVES PIVOT AROUND THE MEAN FLOW THROUGH THE PERIOD. AS
HAS BEEN THE STORY FOR THE PAST SEVERAL DAYS...MODEL GUIDANCE
DISAGREES ON THE TIMING AND POTENCY OF EACH SHORTWAVE...BUT THE
OVERALL IMPACT OF EACH SYSTEM ON OUR AREA WILL BE TO MAINTAIN CHANCE
POPS ACROSS THE AREA AND PERHAPS SUPPORT OVERNIGHT CONVECTION.

THROUGHOUT THE WORK WEEK...HIGH TEMPERATURES WILL REMAIN NEAR NORMAL.
WHILE THERE IS STILL PLENTY OF TIME FOR THE FORECAST TO CHANGE...THE
CURRENT OUTLOOK FOR THE INDEPENDENCE DAY WEEKEND CALLS FOR ISOLATED
TO SCATTERED DIURNAL CONVECTION WITH TEMPERATURES SLIGHTLY ABOVE
NORMAL.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AT KCLT...DRYING AND SCOURING EARLY THIS MORNING WILL LESSEN THE
POSSIBILITY OF STRATUS CIGS DEVELOPING...ESPECIALLY HEADING TOWARD
DAYBREAK. FOR THE DAYLIGHT HOURS...MOSTLY CLEAR CONDITIONS ARE ON TAP
WITH NW WINDS THIS MORNING BACKING TO WSW THIS AFTERNOON.

ELSEWHERE...AREAS OF PIEDMONT STRATUS SHOULD DISSIPATE AS THE
PRE-DAWN HOURS WEAR ON...OTHERWISE VFR THROUGH THE PERIOD.

OUTLOOK...A DRY AIRMASS WILL PERSIST OVER THE REGION THROUGH
EARLY WEEK...BRINGING MOSTLY VFR CONDITIONS. AN ACTIVE PATTERN WILL
RETURN BY MID-WEEK...WITH PERIODIC SHRA/TSRA POSSIBLY BRINGING
RESTRICTIONS.

CONFIDENCE TABLE...

            05-11Z        11-17Z        17-23Z        23-00Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       LOW   56%     LOW   31%     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...WIMBERLEY
NEAR TERM...JDL/WIMBERLEY
SHORT TERM...TS
LONG TERM...JMP
AVIATION...CSH/WIMBERLEY



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.