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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 041637
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1137 AM EST WED DEC 4 2013

.SYNOPSIS...
ANOTHER WARM FRONT CROSSES TODAY. SLOW MOVING COLD FRONT FOR
THURSDAY AND FRIDAY WITH ABUNDANT PRECIPITATION. BRIEF HIGH
PRESSURE SATURDAY. ANOTHER WET SYSTEM SUNDAY AND MONDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
915 AM UPDATE...UPDATED HOURLY TEMPS TODAY BASED ON CURRENT
TRENDS. APPEARS WARM FRONT HAS MOVED THROUGH KLEX AND KLOZ...HAVE
IT TIMED TO NE KY ZONES 16-17Z.

PREVIOUS DISCUSSION BELOW...

WARM AIR ADVECTION REALLY GETS CRANKING TODAY ON STRENGTHENING SW
FLOW ALOFT. WILL BE TRACKING ANOTHER WARM FRONTAL BOUNDARY POISED
TO CROSS THIS AFTERNOON. THERE WILL ALSO BE SOME UPPER AIR SUPPORT
IN CONJUNCTION WITH THIS FEATURE WHICH MAY PROVIDE FOR A FEW LIGHT
RAIN SHOWERS TODAY...MAINLY ACROSS SE OH...WHERE SOME CHANCE POPS
WERE MAINTAINED FROM PREVIOUS FORECAST. OTHERWISE...WILL WE TRYING
TO RID THE AREA OF CLOUDS TODAY WHICH MAY PROVE FUTILE UNTIL THIS
AFTERNOON...ESPECIALLY ACROSS SE OH AND ALSO ALONG THE E SLOPES IN
THE N MOUNTAINS ON LOW LEVEL SE UPSLOPE FLOW.

WARM AIR ADVECTION CONTINUES IN EARNEST TONIGHT AS LOW LEVEL JET
AROUND 50 KTS APPROACHES LATE TONIGHT AHEAD OF THE COLD FRONT.
THIS IN CONJUNCTION WITH TIGHTENING OF THE ISOBARS WILL PROVIDE
FOR A BREEZY NIGHT ACROSS PORTIONS OF SE OH AND ACROSS THE
MOUNTAINS. THINK ENOUGH OF AN INVERSION SETS UP ACROSS THE WV
LOWLANDS TO KEEP THE PUFF OFF UNTIL PREDAWN. THINK SOME 15 TO 20
KT GUSTS ARE POSSIBLE...PARTICULARLY ON THE HIGHER HILLTOPS IN SE
OH AS WELL AS IN THE MOUNTAINS. FRONT LOOKS TO BE STILL W OF A
LINE FROM CLE TO CMH TO CINCY AT 12Z. AS SUCH TRIED TO DELAY THE
POPS AS LONG AS POSSIBLE WITH SOME HELP FROM A DOWNSLOPING
COMPONENT NEAR THE SURFACE. STILL...BRING IN HIGH CHANCE AND LOW
LIKELY ACROSS PORTIONS OF SE OH BY SAID TIME.

FOR TEMPS...HARD TO FIGURE THE GUIDANCE GIVEN FLIP FLOP
VERIFICATION FOR HIGHS THE PAST COUPLE OF DAYS BETWEEN THE MET AND
THE MAV. WILL OPT FOR A BLEND...CLOSE TO IN HOUSE LOCAL MOS
GUIDANCE. DID HEDGE TOWARD WARMER MET ACROSS THE I79 CORRIDOR AND
TYGART VALLEY WHERE SOME COMPRESSIONAL WARMING EFFECTS FROM
DOWNSLOPING SE LOW LEVEL FLOW SHOULD GIVE THOSE AREAS A BOOST.
HAVE MOST PLACES IN THE 62 TO 65F RANGE OUTSIDE OF THE HIGH
TERRAIN. HAVE GENERALLY 50S IN THE HIGHER TERRAIN EXCEPT TYGART
VALLEY WHERE AFOREMENTIONED LOCAL EFFECTS SHOULD GET TEMPS TO PAST
THE 60 DEGREE MARK. TONIGHT...ROLLED ON THE WARMEST SIDE OF THE
ENVELOPE ALONG AND W OF THE OH RIVER WHERE BL PUFF SHOULD KEEP
THINGS MIXED. THE W LOWLANDS AND SE OH MAY BE HARD PRESSED TO DIP
MUCH BELOW THE UPPER 50S. FURTHER E SOME DECOUPLING EARLY MAY
ALLOW TEMPS TO SNEAK BELOW 50 IN SHELTERED LOCATIONS...ESPECIALLY
IN THE MOUNTAIN VALLEY. OVERALL THOUGH A VERY MILD NIGHT
RELATIVELY SPEAKING.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
ECMWF/CANADIAN AND NAM ARE ALL IN FAIRLY GOOD AGREEMENT WITH THE
TIMING OF THE COLD FRONT AND PLACEMENT OF THE ASSOCIATED RAIN SHIELD
WITH THE FRONT AND WAVES MOVING ALONG THE FRONT. THE GFS IS A BIT
FURTHER SOUTH WITH THE RAIN SHIELD. WILL GO WITH THE MAJORITY AND
EDGE BACK POPS IN THE SOUTHEAST ON THURSDAY IN ADVANCE OF THE FRONT.
MODELS ARE ALSO IN FAIRLY GOOD AGREEMENT ON THE EXITING
PRECIPITATION FRIDAY NIGHT...SO WILL REMOVE POPS ON SATURDAY. MODELS
STILL SHOWING LOTS OF PRECIPITATION WITH THIS SYSTEM. WILL HAVE TO
CONTINUE TO MONITOR FOR A FLOOD THREAT. SECOND ROUND ON SUNDAY AND
MONDAY MAY BE THE BIGGER THREAT IN THAT REGARD...AS THE FIRST SYSTEM
WILL SATURATE THE GROUND AND FILL THE RIVERS.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
-- Changed Discussion --
GENERALLY FOLLOWED WPC THINKING WITH SOME TWEAKS FOR LATEST MODEL
TRENDS.

PERIOD SHOULD BEGIN WITH AN AREA OF LOW PRESSURE OFF THE LA COAST
AND AN AREA OF HIGH PRESSURE OVER PA/NY.

THE LOW IS EXPECTED TO LIFT NORTH TO THE GREAT LAKES...WITH A WARM
FRONT LIFTING ACROSS THE REGION BY MONDAY MORNING.

EXPECT PRECIPITATION CHANCES WILL INCREASE FROM THE SOUTH SATURDAY
NIGHT INTO SUNDAY. SURFACE TEMPS SATURDAY NIGHT SHOULD BEGIN BELOW
FREEZING WITH TEMPS ALOFT AT OR ABOVE FREEZING.  PRECIPITATION WILL
LIKELY BEGIN AS A MIXTURE OF SNOW...SLEET AND FREEZING RAIN.
HOWEVER...THE PRECIPITATION SHOULD THEN CHANGE TO ALL RAIN SUNDAY
ACROSS THE LOWLANDS...WITH A WINTRY MIXTURE EXPECTED TO CONTINUE
ACROSS THE HIGHER ELEVATIONS INTO MONDAY.

HAVE GONE WITH CATEGORICAL POPS ACROSS PARTS OF THE REGION SUNDAY
AND SUNDAY NIGHT. IN ADDITION TO ANY WINTRY CONDITIONS THAT
DEVELOP...RAINFALL AMOUNTS WILL ALSO HAVE TO BE MONITORED.

AN ASSOCIATED COLD FRONT WILL PUSH EAST ON MONDAY...WITH A RIDGE
OF HIGH PRESSURE FINALLY BUILDING INTO THE AREA BY LATE TUESDAY.

AS THE COLDER AIR FILTERS IN BEHIND THE FRONT...PRECIPITATION MAY
MIX WITH SLEET AND FREEZING RAIN BEFORE CHANGING TO SNOW MONDAY
NIGHT.

PRECIPITATION CHANCES WILL COME TO AN END ACROSS MUCH OF THE AREA BY
LATE TUESDAY.
-- End Changed Discussion --

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
-- Changed Discussion --
MAINLY VFR CONDITIONS EXPECTED THROUGH THE PERIOD WITH VARYING
BASES AMID MID/HI CLOUDS ALONG WITH 4 TO 6 THSD FOOT CIGS. THERE
WILL BE A FEW EXCEPTIONS. SOME MVFR STRATUS MAY MOVE INTO NE KY
AND SE OH THIS MORNING...PERHAPS GIVING KHTS A FEW HRS OF MVFR
CIGS THIS MORNING. ALSO...MOIST SE FLOW JUST OFF THE SURFACE
WILL KEEP MVFR CIGS ACROSS POCAHONTAS CO THRU 15Z AND ALONG THE E
SLOPES IN THE WV MOUNTAINS. MVFR CIGS ACROSS SE OH TONIGHT WITH
APPROACHING COLD FRONT. SOME MVFR CIGS MAY SNEAK INTO KBKW TONIGHT
ON SE FLOW.

SW FLOW STRENGTHENS HEADING INTO TONIGHT WITH LOW LEVEL JET ON
ORDER OF 50 KTS AT H85 APPROACHES AHEAD OF COLD FRONT LATE. WINDS
OUT OF S TO SSE CLOSE TO THE SURFACE WILL PREVAIL AND BECOME GUSTY
TONIGHT ACROSS THE HIGHER MOUNTAINOUS TERRAIN AND ALONG THE E
SLOPES TO INCLUDE KBKW WHERE 15 TO 20 KT GUSTS ARE POSSIBLE. THIS
MAY ALSO HOLD TRUE FOR SE OH. THINK ENOUGH OF AN INVERSION SETS UP
ACROSS WV LOWLAND TAF SITES TO KEEP PUFF OFF THE DECK UNTIL CLOSER
TO 12Z THU. OH RIVER SITES THOUGH TOUGH CALL THOUGH.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z THURSDAY...


FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: MVFR CEILING PLACEMENT AND TIMING MAY VARY
THROUGH MORNING FOR SE OH AND E SLOPE OF WV MOUNTAINS.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

UTC 1HRLY       14   15   16   17   18   19   20   21   22   23   00   01
EST 1HRLY       09   10   11   12   13   14   15   16   17   18   19   20
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H

AFTER 18Z THURSDAY...
IFR POSSIBLE IN RAIN THURSDAY NIGHT INTO FRIDAY NIGHT.
-- End Changed Discussion --

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.

&&

$$
SYNOPSIS...RPY/JMV/30
NEAR TERM...MZ/30
SHORT TERM...RPY
LONG TERM...JSH
AVIATION...30