Area Forecast Discussion
Issued by NWS Greer, SC

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000
FXUS62 KGSP 290714
AFDGSP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
314 AM EDT FRI APR 29 2016

.SYNOPSIS...
HIGH PRESSURE WILL BUILD IN FRIDAY INTO SATURDAY. A LOW PRESSURE
SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY THROUGH SUNDAY
NIGHT BRINGING A CHANCE OF THUNDERSTORMS TO THE AREA. THE LOW WILL LIFT
NORTHEAST ALONG THE COAST EARLY NEXT WEEK...BUT LEAVE A TRAILING
COLD FRONT NEAR THE CAROLINA COAST.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 AM EDT...ONLY WRINKLE IN AN OTHERWISE QUIET OVERNIGHT WILL
BE THE LOW STRATUS CLOUD DECK OOZING INTO THE NW PIEDMONT ZONES.
THIS COULD NECESSITATE AN UPDATE LATER THIS MORNING IF IT KEEPS
DRIFTING TOWARD CHARLOTTE. TEMPS LOOK OK.

THE NEXT 24 HOURS SHOULD BE FAIRLY QUIET...BUT QUITE WARM. AN UPPER
LEVEL RIDGE WILL MOVE OVERHEAD TODAY...WITH DRIER AIR AT THE SURFACE
AND A WARM LAYER ALOFT THAT ACTS AS AN EFFECTIVE CAP TO KEEP A LID
ON THE DEEP CONVECTION. THE WESTERLY FLOW ALOFT WILL ALSO HELP TO
RAISE TEMPS E OF THE MTNS AND DRY OUT THE BOUNDARY LAYER. THUS...WE
MAY FLIRT WITH RECORD HIGHS...ALTHO THE FCST AS CONSTRUCTED WOULD
HAVE US FALLING SHORT BY A FEW DEGREES. THE MODEL GUIDANCE SUGGESTS
THAT A SHORT WAVE WILL MOVE IN FROM THE WEST LATE TONIGHT. THINK
THIS WILL BRING LITTLE MORE THAN AN INCREASE IN MID/UPPER LEVEL
CONVECTIVE DEBRIS CLOUDINESS. ANY PRECIP ASSOCIATED WITH THE NEXT
SYSTEM TO THE WEST WILL MOST LIKELY NOT REACH THE MTNS BEFORE
DAYBREAK ON SATURDAY. THE INCREASING CLOUDS LATE TONIGHT SHOULD KEEP
TEMPS SEASONALLY MILD WITH LOW TEMPS NEARLY TEN DEGREES ABOVE NORMAL.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300AM EDT FRIDAY MORNING...NEXT CHANCE FOR PRECIP APPEARS TO
BE SATURDAY AFTERNOON AS UPPER SYSTEM MAKES ITS WAY INTO THE CENTRAL
PLAINS WITH A GOOD FETCH OF GULF MOISTURE AHEAD OF IT IN MUCH OF THE
SE CONUS. HEAVIEST PRECIP IS EXPECTED ON SUNDAY AS QG-FORCING WITH
THE UPPER WAVE REACHES THE APPALACHIANS...CONTINUING INTO MONDAY.
COLD FRONT MONDAY MORNING ENDS SIGNIFICANT RAIN FOR TUESDAY...BUT
PASSAGE OF A SMALLER UPPER IMPULSE COULD CREATE SOME SHOWERS ON
WEDNESDAY...THOUGH WITH MUCH LESS BL MOISTURE TO WORK WITH.  TOTAL
PRECIP EXPECTED FOR SATURDAY THROUGH MONDAY IS AROUND AN INCH.

WITH GOOD DEEP BL MOISTURE ADVECTION WITH THE SATURDAY-MONDAY
SYSTEM...CONVECTIVE INSTABILITY WILL BE RISING AS WELL, REACHING AN
LI OF AROUND -4 SATURDAY AFTERNOON AND -5 SUNDAY AFTERNOON. BULK
SHEAR IS NOT PARTICULARLY IMPRESSIVE AT AROUND 30KTS SATURDAY AND
35KTS ON SUNDAY.  NONETHELESS...THE DOMINANT FORM OF PRECIP. SATURDAY
AND SUNDAY AFTERNOON WILL BE THUNDERSTORMS...WITH SOME LOW-END
SEVERE HAIL AND MICRO/MACRO BURSTS POSSIBLE.

HIGH TEMPERATURES WILL DROP 10 DEGREES FROM THE LOW 80S SATURDAY
THROUGH MONDAY DOWN TO THE LOW 70S TUESDAY THROUGH FRIDAY BEHIND THE
FROPA MONDAY AFTERNOON.  EC MODEL IS SLOWER WITH FROPA MONDAY THAN
THE GFS MODEL...THOUGH OTHER FEATURES ARE SIMILAR THROUGH MONDAY
MORNING.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300AM FRIDAY...RAIN CHANCES DECLINE WITH MAJOR COLD FROPA
MONDAY.  TEMPERATURES ALSO DECLINE BY 10 DEGREES FOR TUESDAY-THURSDAY
BEHIND THE FRONT.  TUESDAY IS EXPECTED TO BE DRY IN THE GFS MODEL ON
TUESDAY WITH A CHANCE OF RAIN RETURNING ON WEDNESDAY AS A SMALL
UPPER SYSTEM CROSSES SOUTHERN STATES.  PRECIP AMOUNTS WITH ACTIVITY
WEDNESDAY WILL BE LIGHT DUE TO SCOURING OF MOISTURE BY COLD FRONT.
THERE IS CONSIDERABLE EC-GFS DISAGREEMENT FOR TUESDAY THROUGH FRIDAY
WITH THE EC MODEL ACTUALLY HAVING PRECIP ON TUESDAY.  BOTH MODELS
TEND TO SHOW THE DEVELOPMENT OF A DEEP UPPER LONG WAVE TROUGH OVER
THE EASTERN CONUS...BUT DIFFER IN MAJOR WAYS IN DETAILS OF TIMING
AND PLACEMENT OF SURFACE FEATURES AND PRECIP.  CURRENT FORECAST IS A
BLEND OF THE POSSIBILITIES...WITH SOME CHANCE FOR RAIN MOST DAYS.
THOUGH THE EC MODEL IS WETTER THROUGH THE PERIOD...NEITHER IT NOR
THE GFS MODEL HAVE MORE THAN A HALF INCH FOR TUESDAY THROUGH FRIDAY
DUE TO A LACK OF GOOD MOISTURE ADVECTION INTO THE REGION.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
AT KCLT...VFR THROUGH THE PERIOD...WITH A CATCH. SATELLITE IMAGERY
SHOWS AN AREA OF IFR STRATUS...LEFT OVER IN PART FROM EARLIER
CONVECTION...OVER THE NW PIEDMONT OF NC. THIS IFR CLOUD DECK WAS
OOZING ITS WAY TOWARD THE S AND SW AT 06Z. MODEL GUIDANCE HAS IT NOT
REACHING KCLT. HOWEVER...WE SHALL HAVE TO KEEP AN EYE ON ITS
PROGRESS.  WILL NOT INCLUDE ANY LOW CLOUDS FOR NOW. OTHERWISE...
EXPECT ONLY CIRRUS TODAY...WITH SOME THICKENING MID/HIGH CLOUDS
AFTER SUNSET AHEAD OF THE NEXT SYSTEM. WINDS WILL GENERALLY BE
LIGHT...BUT THE DIRECTION WILL BE TRICKY. A NORTHERLY DIRECTION IS
EXPECTED OVERNITE AND FRIDAY MORNING. HOWEVER...A LEE TROF MAY
DEVELOP BY MIDDAY WHICH WOULD BRING THE LIGHT WIND AROUND TO THE SW.
HAVE DONE THIS AT 17Z.

ELSEWHERE...A FOG BANK WITH MVFR VIS WAS INCLUDED AT KHKY AROUND
DAYBREAK OWING TO THE CLOSE PROXIMITY OF SHOWERS ON THURSDAY.
OTHERWISE...A SIMILAR IDEA TO THAT OF KCLT.

OUTLOOK...VFR CONDITIONS SHOULD PERSIST INTO SATURDAY MORNING.
UNSETTLED WEATHER/POSSIBLE RESTRICTIONS/CONVECTION RETURN FROM THE
WEST BY SUNDAY.

CONFIDENCE TABLE...

            07-13Z        13-19Z        19-01Z        01-06Z
KCLT       HIGH  97%     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  86%     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 SCHEDULE TAF ISSUANCE FLIGHT RULE CATEGORY.  COMPLET HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK:

WWW.WEATHER.GOV/GSP/AVIATION

&&

.CLIMATE...
ERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      89 1970     46 1999     63 1956     28 1967
   KCLT      91 1888     48 1999     65 1994     33 1973
                                        1991
                                        1914
   KGSP      91 1917     47 1999     67 1975     32 1992



RECORDS FOR 04-30

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      87 1962     50 1925     61 1950     31 2008
   KCLT      91 1962     57 1999     66 1991     37 2008
                                        1893
   KGSP      91 1987     55 1934     64 1991     39 2008
                1962                                1980



RECORDS FOR 05-01

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      87 1962     52 1925     65 2012     32 1996
                            1918
   KCLT      92 1962     56 1883     65 1991     37 1963
                                        1951        1908
                                        1907
   KGSP      90 2007     59 1918     66 1951     36 1908
                1962
                1887



RECORDS FOR 05-02

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      88 1935     51 1945     66 2010     33 1963
                                                    1918
   KCLT      91 1959     55 1945     71 2010     32 1963
   KGSP      91 1887     56 1945     68 2010     38 1963
                                                    1908



RECORDS FOR 05-03

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      85 1965     45 1921     65 2010     31 1909
                1959                    1935
                1938
   KCLT      94 1902     57 1945     70 1901     39 1981
                            1921
   KGSP      91 1959     56 1921     68 2010     27 1885
                1887



RECORDS FOR 05-04

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      88 1996     47 1945     62 2012     29 1986
                                        1887        1971
   KCLT      92 1959     50 1946     68 1935     34 1971
                1938
                1928
   KGSP      91 1887     51 1946     67 2012     30 1885
                                        1979



RECORDS FOR 05-05

               MAX TEMPERATURE         MIN TEMPERATURE
  STATION      HIGH        LOW         HIGH        LOW
  -------  ----------  ----------  ----------  ----------
   KAVL      90 1950     50 1921     64 1953     32 1997
   KCLT      91 1955     57 1961     67 1953     36 2011
                1913
   KGSP      91 2014     54 2013     67 1953     35 1885
                1934

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

&&

$$
SYNOPSIS...SBK/WJM
NEAR TERM...PM
SHORT TERM...WJM
LONG TERM...WJM
AVIATION...PM
CLIMATE...



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