Area Forecast Discussion
Issued by NWS Greer, SC

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FXUS62 KGSP 291751
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
151 PM EDT MON JUN 29 2015

.SYNOPSIS...
MOISTURE WILL GRADUALLY RETURN TO THE REGION STARTING TODAY WITH
THE NEXT FRONT APPROACHING BY THE MIDDLE OF THE WEEK. THIS WILL LEAD
TO INCREASED SHOWER AND THUNDERSTORM CHANCES TUESDAY AND WEDNESDAY
WITH HIGH TEMPERATURES RETURNING TO NEAR NORMAL LEVELS.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM...REGIONAL RADAR INDICATES THAT THE EARLIER SHRA ACROSS
EASTERN TN HAVE DISSIPATED. LATEST SPS CAPE ANALYSIS INDICATED THAT
THE CWA REMAINS STABLE...WITH 100-200 J/KG ACROSS THE EXTREME
WESTERN NC MTNS. I WILL UPDATE THE FORECAST TO REDUCE POPS THROUGH
THE EARLY AND MID AFTERNOON...THEN INCREASE TO SCHC TO CHC ALONG THE
TN BORDER LATE THIS AFTERNOON AND EVENING. I WILL ALSO MAKE MINOR
EDITS TO TEMPS AND DEWPOINTS.

AS OF 11 AM...LATEST SATELLITE IMAGES INDICATE A FEW PATCHES OF MID
CLOUDS OVER THE FOOTHILLS...WITH CU OVER GRAHAM AND SWAIN COUNTIES.
REGIONAL RADAR COMPOSITE INDICATED A FEW SHRAS ACROSS EASTERN
TN...TRACKING EAST. A FEW OF THE LEADING SHRAS HAVE WEAKEN AS THEY
MOVED INTO A MORE STABLE ENVIRONMENT. THE CURRENT FORECAST TREND
APPEARS WELL TIMED...WITH SCHC TO CHC POPS ALONG THE TN BORDER
DURING THE HEAT OF THIS AFTERNOON. I WILL UPDATE THE FORECAST TO
MAKE MINOR ADJUSTMENT TO THE TEMPERATURES AND SKY.

AS OF 9 AM...TEMPERATURES HAVE WARMED QUICKLY FROM GENERALLY COOL
MORNING TEMPERATURES...RISING 10 TO 15 DEGREES FROM MINS. I WILL
UPDATE THE FORECAST TO ADJUST HOURLY TEMPERATURES TO OBSERVATIONS.
RECENT MESOSCALE ANALYSIS INDICATED A WEAK LOW NEAR THE NC/SC STATE
LINE OVER THE PEE DEE REGION. A WEAK FRONT ASSOCIATED WITH THE LOW
DRAPED SW ACROSS THE SC/GA ACROSS THE COASTAL PLAIN. THE DEPARTING
LOW SHOULD SUPPORT WEAK NE WINDS THROUGH MOST OF THE MORNING.
HOWEVER...RETURN SW FLOW SHOULD DEVELOP EARLY THIS AFTERNOON AND
REMAIN INTO THE EVENING. I WILL UPDATE TO ADJUST WIND TIMING AND
SPEED.

0830 UTC UPDATE...SKY COVER WAS UPDATED PER INFRARED SATELLITE
IMAGERY TO ACCOUNT FOR A THIN STREAK OF HIGH CLOUDS MOVING NORTHEAST
FROM THE GULF STATES.

AS OF 300 AM...AN ANOMALOUS HIGH AMPLITUDE UPPER TROUGH WILL BE
OVER EASTERN NORTH AMERICA TODAY AND TONIGHT. WEAK SHORTWAVE ENERGY
MOVING THROUGH THIS TROUGH WILL CROSS THE SOUTHERN APPALACHIANS THIS
EVENING AND AGAIN AROUND TUESDAY MORNING. LOW LEVEL MOISTURE
ASSOCIATED WITH THE REMAINS OF A FRONT NOW IN THE MS RIVER VALLEY
WILL REACH THE MOUNTAINS BY MIDDAY...SPREADING ACROSS THE AREA THIS
AFTERNOON...AND PERSISTING INTO TONIGHT. INSTABILITY WILL BE BEST IN
THE MOUNTAINS...CLOSEST TO THE TROUGH AXIS...AND THIS IS WHERE THE
GREATEST THUNDERSTORMS COVERAGE WILL BE CARRIED. ALTHOUGH CAPE IS
RATHER LIMITED...SOME SHEAR WILL EXIST. STEERING FLOW WILL KEEP
CELLS MOVING...AND LOW LEVEL FLOW WILL BE NEARLY PARALLEL TO THE
BLUE RIDGE...LIMITING UPSLOPE FLOW. TEMPERATURES WILL RUN SLIGHTLY
BELOW NORMAL IN A RELATIVELY COOL AIRMASS AND BELOW NORMAL HEIGHTS
ALOFT.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 130 AM MONDAY...THE AMPLIFIED PATTERN WILL LINGER THROUGH THE
PERIOD WITH MEAN L/WV TROUGH AXIS ATOP THE EASTERN CONUS.
EXPECTEDLY...THE DEEP LAYERED FLOW WILL BE UNSEASONABLY QUICK AND
AVERAGE FROM THE WSW. WITHIN THE WSW LLVL FLOW...MOISTURE RETURN AND
DESTABILIZATION WILL BE MODEST...YET STEADY...ALLOWING DAILY
DIURNALLY ENHANCED TSTMS TO INCREASE EACH DAY TO ABOVE CLIMO
VALUES. GIVEN THE ABNORMALLY AMPLIFIED FLOW FOR THIS TIME OF
THE YEAR...SFC-6 KM SHEAR VALUES WILL GIVE RISE TO POTENTIAL
FOR ORGANIZED DEEP CONVECTION EACH AFTERNOON/EVENING LEADING
TO SCATTERED SVR TSTMS. TEMPERATURES EACH DAY WILL BE CLOSE TO
PERSISTENCE AND THE LATE JUNE CLIMO.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 215 AM MONDAY...IT IS LOOKING LIKE THERE WILL BE A SLOW/TOKEN
RISE IN HEIGHTS ATOP THE REGION FOR THE LATTER HALF OF THE
WORKWEEK...PROBABLY KEEPING THE PROGGED WAVY FRONT/BAROCLINIC
ZONE EXTENDING FROM THE OHIO VALLEY TO MID-ATLANTIC OFF TO OUR
NORTH. HOWEVER...WITH SOME DEGREE OF ABNORMAL AMPLIFICATION TO
THE MEAN PATTERN TO START OFF JULY...DAILY THUNDERSTORM CHANCES
SHOULD AVERAGE HIGHER THEN CLIMO. HEADING INTO THE HOLIDAY
WEEKEND...IT REMAINS TO BE SEEN HOW FAR INTO THE SE CONUS THAT
BERMUDA HIPRES ASSERTS ITSELF...BUT AT THIS POINT...THERE/S REALLY
NO REASON TO DEVIATE FROM THE INHERITED FCST WHICH IS TYPICAL EARLY
JULY CONDITIONS.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AT KCLT AND ELSEWHERE...LATEST SATELLITE IMAGE INDICATED A BAND OF
DEBRIS CLOUDS ACROSS THE NC MTNS...WITH A SHALLOW CU FIELD ACROSS
THE NC AND NRN SC FOOTHILLS AND PIEDMONT. A FEW SHRA TO ISO TSRA MAY
REACH THE TN BORDER COUNTIES OF NC BEFORE DISSIPATING THIS EVENING.
OTHERWISE...CONDITIONS ACROSS THE WESTERN CAROLINAS SHOULD REMAIN
QUIET...WITH A LIGHT SW CONTINUING THROUGH TONIGHT.

ON TUESDAY...CONDITIONS WILL BECOME MUCH MORE SUMMER-LIKE. THE
PASSAGE OF A MID LEVEL WAVE COMBINED WITH HIGHER LLVL DEWPOINTS WILL
YIELD AN ENVIRONMENT MORE SUITABLE FOR TSRAS. KAVL WILL SEE THE
GREATEST CHC DURING THE 18Z PACKAGE...I WILL HIGHLIGHT WITH A
PROB30. ELSEWHERE...TSRA SHOULD HOLD OFF UNTIL AFTER 18Z. IN
ADDITION...DEEP MIXING SHOULD YIELD MARGINAL WIND GUSTS DURING THE
AFTERNOON...KAND TO KGSP BEFORE 18Z.

OUTLOOK...A LINGERING BERMUDA HIGH COMBINED WITH AN AMPLIFYING
LONGWAVE TROF OVER THE SOUTHEAST WILL GRADUALLY INCREASE MOISTURE
AND INSTABILITY THROUGH MOST OF THE WORK WEEK. THUNDERSTORM COVERAGE
MAY INCREASE EACH DAY THROUGH WEDNESDAY...WITH SCT TO NUM DIURNAL
THUNDERSTORMS LATE IN THE WEEK. RESTRICTIONS MAY OCCUR WITH PASSING
STORMS...AND EACH MORNING OVER AREAS OF WET SOIL.

CONFIDENCE TABLE...

            18-24Z        00-06Z        06-12Z        12-18Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH  93%
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  86%
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...CSH
NEAR TERM...NED
SHORT TERM...CSH
LONG TERM...CSH
AVIATION...NED


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