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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 161930
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
230 PM EST MON DEC 16 2013

.SYNOPSIS...
-- Changed Discussion --
SHORTWAVE TROUGH PUSHES A WARM FRONT NORTH TONIGHT...FOLLOWED BY
A COLD FRONT TUESDAY. HIGH PRESSURE CROSSES WEDNESDAY. NEXT SYSTEM
LATE WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TUESDAY/...
-- Changed Discussion --
OVERALL NOT MUCH CHANGE WITH REGARD TO PREVIOUS FORECAST THINKING
EARLY THIS AFTERNOON FOR THIS PERIOD. BAROCLINIC ZONE STILL EVIDENT
ACROSS THE FAR NORTHERN PART OF THE AREA EARLY THIS
AFTERNOON...WHICH WILL SLOWLY RETREAT NORTHWARD THIS EVENING AND
OVERNIGHT. THIS WILL INTERACT WITH ANOTHER S/W TROUGH PUSHING ACROSS
AS WELL. BEST LARGE SCALE FORCING FOR ASCENT WILL ENTER AND QUICKLY
PUSH ACROSS FROM ROUGHLY 06Z-12Z TUE. BEST DYNAMICS AND MOISTURE
WILL RESIDE ACROSS THE FAR NORTHERN ZONES AND FURTHER NORTH AND WILL
CARRY HIGH LIKELY POPS ACROSS THOSE AREAS OVERNIGHT...TAPERING TO
JUST A SLIGHT CHANCE FURTHER SOUTH ALONG THE I64 CORRIDOR. AS WARM
FRONT RETREATS NORTHWARD...EXPECT OVERNIGHT TEMPS TO REMAIN FAIRLY
STEADY FOR THE MOST PART...WHICH PREV FCST HAD A GOOD HANDLE ON.
WITH THE WARMER TEMPS...EXPECTING PRECIP TO FALL AS RAIN FOR MOST
LOWLAND LOCATIONS. NORTHERN LOWLANDS HOWEVER SHOULD REMAIN ALL SNOW
OR AT LEAST A MIX FOR MUCH OF THE OVERNIGHT HOURS WITH WET BULB ZERO
HEIGHTS REMAINING AT OR BELOW 1KFT AGL. SNOW ACCUMS SHOULD REMAIN
LIGHT HOWEVER...WITH PERHAPS A HALF INCH OR SO GIVE OR TAKE ACROSS
THE FAR NW ZONES BY 12Z TUE AND AROUND THE SAME FOR THE NORTHERN
MOUNTAIN AREAS. EXPECTING ANOTHER GENERAL LULL IN PRECIP COVERAGE
DURING THE MORNING HOURS AS THIS S/W TROUGH EXITS...BUT PRECIP RAMPS
UP AGAIN BY THE AFTERNOON HOURS AS A MORE STOUT S/W TROUGH WITH
COLD FRONT ROTATE AROUND THE LOW OVER THE NORTHERN GREAT LAKES. NEAR
AND NORTH OF A LINE ROUGHLY FROM CKB-PKB AND INTO THE NW
ZONES...PRECIP MAY INITIALLY BEGIN AS LIGHT RAIN HERE BUT A DECENT
DEWPOINT DEPRESSION AND RESULTANT WET BULB ZERO HEIGHTS WOULD
INDICATE A FAIRLY QUICK CHANGEOVER TO A RAIN/SNOW MIX TO ALL SNOW.
STILL HOWEVER...TEMPS REMAIN IN THE LOW/MID 30S SO ACCUMS SHOULD BE
CONFINED MOSTLY TO GRASSY AREAS. ACROSS THE CENTRAL WV LOWLANDS
PRECIP STARTS AS RAIN AND WILL TAKE A BIT LONGER TO TRANSITION TO A
MIX AND SNOW...CLOSER TO 22Z TUE - 00Z WED.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
SERIES OF UPPER SHORTWAVE TROUGHS WILL STREAK THROUGH THE AREA IN
THE SHORT TERM PERIOD. ONE WHICH WILL BE EXITING TO THE EAST OF THE
AREA ON TUESDAY...WITH JUST A FEW LINGERING UPSLOPE SHOWERS MAINLY
ACROSS THE NORTH TUESDAY...FOLLOWED BY ANOTHER TUESDAY NIGHT THROUGH
EARLY WEDNESDAY. BOTH OF THESE DISTURBANCES WILL AFFECT MAINLY
NORTHERN ZONES...AND HIGHER TERRAIN COUNTIES. PRECIPITATION WITH
BOTH OF THESE WAVES LOOKS TO BE RATHER LIGHT. WITH PLENTY OF COLD
AIR ALOFT...AND SATURATION IN THE CRYSTAL GROWTH ZONE...EXPECT MOST
PRECIPITATION TO MAKE IT TO THE GROUND AS EITHER LIGHT SNOW OR A
MIX...ALTHOUGH LOWLAND ZONES MAY TRANSITION TO A PERIOD OF RAIN
TUESDAY AFTERNOON.

HIGH PRESSURE WILL GRADUALLY BUILD INTO THE REGION WEDNESDAY INTO
THURSDAY...WITH DRIER WEATHER...AND A GRADUAL CLEARING OF SKY COVER
TAKING HOLD.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
MODEL AGREEMENT ON HIGH PRESSURE DOMINATING OUR AREA THURSDAY INTO
FRIDAY. WITH THE HIGH SHIFTING EAST...EXPECT TEMPERATURES TO REBOUND
TO ABOVE NORMAL READINGS...ESPECIALLY FRIDAY EVEN AS THE SIGNIFICANT
CLOUDS ARRIVE FROM THE WEST FROM THE NEXT SYSTEM.

GIVEN 12Z MODEL TRENDS...WILL QUICKEN WPC THINKING ON THE NEXT
SIGNIFICANT SYSTEM AFFECTING US BY THE END OF THE WEEK. THE GFS
STILL LOOKS TOO FAST IN EJECTING INITIAL LOW PRESSURE SYSTEM AND
ASSOCIATED COLD FRONT OUT OF THE DEEP WESTERN U.S. UPPER TROUGH.
HOWEVER...THE FRONT NOW LOOKS TO LEAN OVER INTO THE NORTHERN HALF OF
THE AREA FRIDAY NIGHT...THEN LIFT BACK NORTH AS A WARM FRONT LATER
SATURDAY AS THE MAIN LOW PRESSURE SYSTEM LIFTS OUT THROUGH THE
WESTERN OHIO RIVER VALLEY SATURDAY NIGHT AND SUNDAY. THUS...WILL
HAVE POPS ARRIVING INTO THE NORTHWEST PORTIONS LATER FRIDAY. EXPECT
THE BEST POPS WILL STAY OVER NORTHWESTERN HALF FRIDAY NIGHT AND
SATURDAY AS THE FRONT STARTS TO RETREAT...THEN OVERSPREAD THE AREA
FROM THE WEST BY SUNDAY AS THE COLD FRONT PUSHES EAST BEHIND THE LOW
PRESSURE SYSTEM. THIS SCENARIO...WHILE BRING COOLER TEMPERATURES TO
NORTHWEST SECTIONS LATER FRIDAY NIGHT AND SATURDAY...WILL KEEP
PRECIP TYPE ALL RAIN TIL PASSAGE OF THE FRONT LATER SUNDAY. IN
GENERAL...WE EXPECT WELL ABOVE NORMAL TEMPERATURES ESPECIALLY SOUTH
AND EAST...DESPITE INCREASING CLOUDS AND SHOWERS THROUGH THE PERIOD.

COLD FRONT SHOULD MOVE EAST OF AREA SUNDAY NIGHT WITH A TYPICAL POST
FRONTAL SNOW SHOWER SCENARIO.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/... 
-- Changed Discussion --
LOW STRATOCU / STRATUS
PERSISTS...WITH SOME BREAKS ACROSS THE FAR SOUTHERN PART OF THE
AREA.

SNOW SHOWERS STILL OVER THE CENTRAL PART OF THE AREA EALRY THIS
AFTERNOON ARE CONTINUING TO WIND DOWN WITH THE PASSAGE OF A SHORT
WAVE TROUGH. STILL EXPECTING A RELATIVE LULL IN PRECIP LATE THIS
AFTERNOON INTO THE EARLY EVENING HOURS. IN THE MEANTIME...THERE
MAY BE SOME BRIEF IMPROVEMENT TO LOW VFR EITHER WITH A RAISED CIG
OR A SCATTERING DURING THIS SAME TIME PERIOD. BUT OVERALL...STILL
PRIMARILY EXPECTING MVFR TO HIGH IFR CIGS DURING THE VALID PERIOD
AS ANOTHER S/W AFFECTS THE AREA OVERNIGHT...WITH YET ANOTHER
STRONGER IMPULSE PUSHING IN TOWARDS THE END OF THE VALID PERIOD.
PRECIP SHOULD BE MAINLY IN THE FORM OF RAIN ACROSS CENTRAL AND
SOUTHERN LOWLANDS TONIGHT AS SFC TEMPS WARM ENOUGH HERE...WHILE
NORTHERN AREAS SUCH AS PKB AND CKB CONTINUE TO SEE LIGHT SNOW
DURING THE OVERNIGHT HOURS...BEFORE TRANSITIONING TO A MIX THEN
RAIN TOWARDS THE 12Z TIME FRAME. WINDS WILL ALSO PICK UP AND
BECOME BREEZY OVERNIGHT FROM THE SOUTHWEST.


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

FORECAST CONFIDENCE: LOW TO MEDIUM.

ALTERNATE SCENARIOS: CIGS STRADDLING HIGH IFR / LOW MVFR THIS
EVENING ACROSS E-CENTRAL OHIO AND NORTHERN WV MAY VARY. TIMING AND
INTENSITY OF PRECIP TONIGHT MAY VARY.

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       20   21   22   23   00   01   02   03   04   05   06   07
EST 1HRLY       15   16   17   18   19   20   21   22   23   00   01   02
CRW CONSISTENCY  H    H    M    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    M    M    M    M    M    H
EKN CONSISTENCY  L    L    L    L    L    L    L    L    L    H    H    M
PKB CONSISTENCY  H    H    H    L    L    L    H    H    H    H    H    H
CKB CONSISTENCY  L    L    L    L    L    L    L    H    H    H    H    M

AFTER 18Z TUESDAY...
IFR IN LOW CIGS INTO TUE AFTERNOON AND EVENING...ESPECIALLY ACROSS
THE WV MOUNTAIN COUNTIES.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...TRM/SL/50
NEAR TERM...50
SHORT TERM...SL
LONG TERM...JMV
AVIATION...50