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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KRAH 042000 RRA
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
300 PM EST WED DEC 4 2013

.SYNOPSIS...
-- Changed Discussion --
A WARM AND MOIST SOUTHERLY FLOW WILL PERSIST THROUGH
FRIDAY...RESULTING IN ABOVE NORMAL TEMPERATURES. A COLD FRONT WILL
MOVE IN FROM THE WEST EARLY SATURDAY.
-- End Changed Discussion --

&&

.NEAR TERM /TODAY THROUGH TONIGHT/...
AS OF 230 PM WEDNESDAY...

THE SHOWER ACTIVITY FROM THIS MORNING CONTINUES TO MOVE OFF THE CAROLINA
COAST AS MODEST HEIGHT RISES MOVE IN FROM THE WEST. SOUTHERLY FLOW WILL
PROVIDE TEMPERATURES IN THE LOWER TO UPPER 60S NW TO SE... DESPITE MOSTLY
CLOUDY CONDITIONS PERSISTING THROUGH THE REST OF THE DAY.

WITH THE MOIST AIRMASS IN PLACE... ANOTHER ROUND OF LOW CLOUDS...
AND POSSIBLY AREAS OF FOG... WILL FORM ACROSS THE AREA OVERNIGHT. AN
AREA OF ISENTROPIC LIFT ACROSS THE WESTERN HALF OF THE STATE MAY
RESULT IN SOME DRIZZLE. TEMPERATURES WILL REMAIN MILD...IN THE MID
50S.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 231 PM WEDNESDAY...

HIGH PRESSURE WILL REMAIN ACROSS THE WESTERN ATLANTIC... AS A COLD
FRONT SLOWLY APPROACHES FROM THE WEST. THE AREA WILL REMAIN IN THE
WARM SECTOR THROUGH FRIDAY. LOW LEVEL THICKNESSES ON THURSDAY WILL
RISE 20M OVER TODAY... AND THAT WILL PUSH HIGHS INTO THE LOW TO MID
70. THE PRESSURE GRADIENT WILL TIGHTEN IN ADVANCE OF THE APPROACHING
COLD FRONT... AND WINDS ON WILL GUST DURING THE AFTERNOON HOURS 15-
20 KTS. LOWS ON THURSDAY IN THE LOW TO MID 60S. FRIDAY WILL BE A FEW
DEGREES WARMER... WITH HIGHS IN THE MID TO UPPER 70S. RAIN SHOWERS
MAY BEGIN TO MOVE INTO THE WESTERN PIEDMONT FRIDAY AFTERNOON... WITH
RAIN MOVING IN OVERNIGHT. FRONT WILL BEGIN TO MOVE ACROSS THE REGION
OVERNIGHT... AND UNFAVORABLE DIURNAL TIMING WILL LIMIT INSTABILITY.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
AS OF 300 PM WEDNESDAY...

GUIDANCE REMAINS IN DECENT AGREEMENT THAT THE COLD FRONT WILL PUSH
ACROSS OUR CWA EARLY SATURDAY MORNING...MOVING S/E OF OUR CWA BY 12Z
SATURDAY. MODELS CONTINUE TO DEPICT THE FRONT ACCOMPANIED BY MOSTLY
ANAFRONTAL PRECIP WITH INCREASING ISENTROPIC LIFT AS THE FRONT MOVES
SOUTH AND WHILE SW FLOW CONTINUES ABOVE THE SFC.  OVERALL...LOOK FOR
MOSTLY CLOUDY AND DAMP CONDITIONS DURING THE DAYTIME SATURDAY.
DESPITE A GRAY/DAMP FEEL TO THE WEATHER...IT WON`T BE RAINING
HEAVILY OR CONTINUOUSLY ALL DAY...AND GFS AND ECMWF BOTH SUGGEST
LESS THAN A HALF INCH QPF DURING THE DAYTIME SATURDAY IN THE WAKE OF
THE FRONT. SATURDAY`S HIGH TEMPS WILL OCCUR BEFORE FROPA AND SUNRISE
SATURDAY MORNING...WITH A QUICK DROP IN TEMPS WITH FROPA...THEN
TEMPS SLOWLY FALLING THROUGH THE 40S DURING THE DAYTIME.

THE MAIN FORECAST PROBLEM WILL OCCUR SATURDAY NIGHT INTO EARLY
SUNDAY AS ARCTIC HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES AND
NORTHEAST...WITH A 1037MB HIGH BECOMING CENTERED OVER NY BY 12Z
SUNDAY...EXTENDING SW ACROSS THE CAROLINAS IN A CLASSIC CAD REGIME.
WITH LITTLE CHANGE IN THE OVERALL PATTERN AND ISENTROPIC ACCENT
CONTINUING...COMBINED WITH COLDER AIR MOVES SOUTH ON N/NE LOW LEVEL
FLOW...LATEST FORECAST SOUNDINGS CONTINUE TO SUGGEST THE POSSIBILITY
FOR A VERY BRIEF PERIOD OF FREEZING RAIN ACROSS THE NORTHWEST
PIEDMONT EARLY SUNDAY MORNING. WHILE RECENT PREVIOUS RUNS HAVE HAD A
SLIGHT WARMING TREND WITH A WEAKER HIGH...THE LATEST FORECAST
SOUNDINGS STILL SUGGEST A VERY BRIEF (AND LOW-IMPACT) PERIOD OF LIGH
FREEZING RAIN ACROSS THE AFOREMENTIONED LOCATIONS...SO THIS CONCERN
WILL NEED TO BE CLOSELY WATCHED WITH SUBSEQUENT MODEL RUNS.

ON SUNDAY...THE CAD REGIME WILL GRADUALLY ERODE LATE IN THE DAY...AS
THE PARENT HIGH IS DEPICTED TO BE RATHER PROGRESSIVE WHILE
CONTINUING SW FLOW WILL HELP PUSH THE OLD COLD FRONT BACK TO OUR
NORTH. WITH THE WEAKENING CAD...LOOK FOR BEST CHANCE FOR RAIN TO
RETREAT NORTH AND WESTWARD AS THE DAY PROGRESSES. OVERALL...STILL
RATHER CLOUDY...DAMP...AND COOL WITH DAYTIME TEMPS STRUGGLING TO
MAKE IT PAST THE LOWER 40S.

MONDAY THROUGH WEDNESDAY...THE NEXT COLD FRONT IS PROGGED TO SLOWLY
MOVES ACROSS OUR CWA MONDAY AND MONDAY NIGHT...FOLLOWED BY HIGH
PRESSURE BUILDING IN FROM THE WEST. STILL SOME UNCERTAINTY WRT HOW
LONG THE CHANCE FOR RAIN LINGERS ACROSS OUR AREA EARLY NEXT
WEEK...AS SW FLOW AND WEAK ISENTROPIC UPGLIDE EXPECTED TO CONTINUE
DURING THIS TIME. WITH LOW CONFIDENCE...WILL OPT TO KEEP CHANCE POPS
IN THE FORECAST. TEMPS WILL BRIEFLY RISE ABOVE NORMAL (INTO THE 60S)
ON MONDAY AHEAD OF THE FRONT...THEN BACK TO NEAR-NORMAL BEHIND THE
FRONT FOR TUESDAY AND WEDNESDAY.
-- End Changed Discussion --

&&

.AVIATION /18Z WEDNESDAY THROUGH SUNDAY/...
AS OF 1250 PM WEDNESDAY...

ADVERSE AVIATION CONDITIONS WILL REMAIN ACROSS THE AREA FOR MUCH OF
THE 24 HOUR PERIOD. GENERALLY IFR TO MVFR CONDITIONS ACROSS THE AREA
WILL LIKELY ONCE AGAIN RETURN TO IFR/LIFR TONIGHT AS LOW STRATUS AND
FOG DEVELOPS IN THE INCREASINGLY MOIST AIRMASS. CONDITIONS WILL
BEGIN TO IMPROVE BY LATE MORNING TO MVFR CONDITIONS... AND LIKELY
VFR THURSDAY AFTERNOON... AS SW WINDS GUST TO 15-20 KTS.

SUB-VFR CONDITIONS ARE LIKELY FRIDAY THROUGH THE WEEKEND AS A COLD
FRONT APPROACHES... WITH UNSETTLED CONDITIONS AND THE CHANCE FOR
RAIN PERSISTING THROUGH THE WEEKEND.

&&

.CLIMATE...

RECORD HIGH TEMPERATURES FOR DECEMBER 6TH:

GSO... 76 SET IN 1998
RDU... 80 SET IN 1998
FAY... 80 SET IN 1998

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE

&&

$$

SYNOPSIS...NP
NEAR TERM...SEC
SHORT TERM...SEC
LONG TERM...NP
AVIATION...SEC
CLIMATE...RAH