-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 081923
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
223 PM EST SUN DEC 8 2013

.SYNOPSIS...
WARM FRONT LIFTS NORTH INTO TONIGHT. ANOTHER SYSTEM PASSES ACROSS THE
SOUTHEAST MONDAY NIGHT AND EARLY TUESDAY. MOSTLY DRY YET CHILLY FOR
REMAINDER OF THE WORK WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
-- Changed Discussion --
JET STREAK INDUCED HEAVY SNOW BAND DECREASING IN INTENSITY AS THE
JET STARTS PULLING OUT. ALSO HAVE WARMER 850 TEMPS GRADUALLY INCHING
NORTHWARD ACROSS CWA RESULTING IN PRECIP CHANGING FROM SNOW TO SLEET
TO RAIN FROM SOUTH TO NORTH. WESTERN CWA WILL HANG ONTO COOLER TEMPS
A BIT LONGER AND SNOW WILL LINGER LONGER. BULK OF THE SNOW/SLEET
ACCUMULATIONS ARE DONE ACROSS THE CWA...WITH BEST CHANCE OF
ADDITIONAL SNOW ACCUMULATION ACROSS THE NORTHWEST CWA AND NORTHERN
MOUNTAINOUS COUNTIES. ATTENTION THEN TURNS TO ONGOING FREEZING RAIN
EVENT. ACROSS THE WV LOWLANDS AND MID OHIO RIVER
VALLEY...TEMPERATURES WILL SLOWLY CLIMB ABOVE FREEZING...BUT EVEN
WITH THE CURRENT TEMPS OF 30-32F...ICE ACCUMULATIONS ON ROADS WILL
BE VERY MINIMAL. CANCELLED SE TIER OF WINTER WEATHER ADVISORY AND
WARNING FROM THIS MORNING AND WILL LINGER THE NORTH AND WEST
PORTION AS TEMPS STILL BELOW FREEZING WITH SNOW/SLEET/RAIN.
FARTHER EAST...IN SE FLOW EXPECT EASTERN SLOPES TO REMAIN BELOW
FREEZING FOR MUCH OF THE DAY. SPECIAL 18Z RNK SOUNDING SHOWS WARM
NOSE OF +7C ALOFT. ANOTHER ENHANCED AREA OF PRECIP ON RADAR
MOVING UP THE SPINE OF WV MOUNTAINS WITH FREEZING RAIN LIKELY.
HAVE SURFACE TEMPS WARMING ABOVE FREEZING IN THE BKW AREA AROUND
00Z AND SWITCHING TO A COLD RAIN. COOLER TEMPS REMAIN IN PLACE
ACROSS THE EASTERN SLOPES/VALLEYS OF THE NORTHERN MOUNTAINS
THROUGH MUCH OF THE NIGHT.

MODELS SHOW ANOTHER SLUG OF MOISTURE TONIGHT. NAM SHOWS HIGHEST QPF
AMOUNTS ACROSS SW VA AND SOUTHERN WV...WHILE GFS IS A BIT FARTHER
NORTH OHRFC HAS ROUGHLY THREE QUARTERS OF AN INCH ACROSS SOUTHERN
ZONES AND WILL GO WITH THAT. PRECIP WILL GRADUALLY CLEAR OUT FROM
WEST TO EAST THROUGH THE DAY TOMORROW.

WARM ADVECTION SHOULD CONTINUE THROUGH THE NIGHT...SO HAVE
NON-DIURNAL TEMPERATURES...BASED HEAVILY ON THE RAW NAM. THIS HAS
MUCH OF THE WV LOWLANDS AND WEST STAYING IN THE MID TO UPPER 30S
OVERNIGHT...WITH NEAR STEADY TEMPS TOMORROW.
-- End Changed Discussion --

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
CONTINUED ACTIVE DURING THE SHORT-TERM...WITH ONE SYSTEM EXITING ON
MONDAY FOLLOWED QUICKLY BY ANOTHER WAVE EARLY TUESDAY.

NOT MUCH CHANGE REGARDING THE LARGE SCALE FEATURES FROM A RUN TO RUN
BASIS WITH VARIOUS SHORT-RANGE AND MED-RANGE MODEL OUTPUT. ON
MONDAY...AREA REMAINS UNDER STRONG SW FLOW ALOFT WITH STRENGTHENING
JET STREAK TO THE NORTHWEST AS A S/W UPPER TROUGH PROGRESSES
EASTWARD INTO THE NW GREAT LAKES. AT THE SURFACE...LOW PRESSURE OFF
TO THE NORTHEAST CONTINUES TO PULL AWAY. ASSOC SFC FRONT WILL
ALREADY BE SOUTHEAST OF THE FORECAST AREA BY 12Z MON...BUT A STOUT
BAROCLINIC ZONE WILL STILL REMAIN ACROSS THE AREA. BEST DEEP LAYER
MOISTURE PUSHES EASTWARD ACROSS THE AREA DURING THE DAY AS THE 850MB
TROUGH AXIS PUSHES ACROSS. NOT MUCH OVERALL CHANGE WITH REGARD TO
PRECIP CHANCES AND/OR AMOUNTS FOR MONDAY...WITH LIKELY TO CAT POPS
GENERALLY EAST OF THE OHIO RIVER AT 12Z MON...TO LIKELY EAST OF THE
I79 CORRIDOR BY 18Z MON...AND ONLY SLIGHT POPS REMAINING ALONG THE
EASTERN MOUNTAINS BY 00Z TUE. ALSO NOT MUCH CHANGE WITH REGARD TO
MAX TEMPS MONDAY. AS AFOREMENTIONED SFC LOW CONTINUES TO PULL
AWAY...WIND DIRECTION WILL GRADUALLY VEER FROM THE SOUTHWEST TO THE
W/NW BY 00Z TUE WHICH WILL INCREASE COLD ADVECTION ACROSS THE AREA
DURING THE AFTERNOON HOURS. STILL EXPECT LOW/MID 40S FOR MUCH OF WV
ZONES...BUT ONLY THE MID/UPPER 30S FURTHER WEST OVER SE OHIO WHERE
COLDER AIR REMAINS ENTRENCHED.

MONDAY NIGHT...COLD AIR ADVECTION CONTINUES INTO THE FORECAST AREA.
LOWERED MINS JUST A TAD WITH LOWS GENERALLY IN THE UPPER 20S/NEAR 30
FOR CENTRAL AND SOUTHERN LOWLANDS...AND LOW 20S SE OHIO AND EASTERN
MOUNTAINS. PRECIP BRIEFLY WINDS DOWN OVER THE AREA MONDAY EVENING
BUT LOOKS TO QUICKLY RAMP UP AGAIN TOWARDS TUESDAY MORNING AS THE
NEXT WAVE ALONG THE FRONT RIDES NORTHEAST WHILE THE UPPER S/W TROUGH
OVER THE UPPER MIDWEST CONTINUES TO DIG OVER THE CENTRAL CONUS...ROUGHLY
LOCATED OVER THE CENTRAL MISS VALLEY BY 12Z TUE. STILL SOME NOTABLE
DIFFERENCES WITH MODEL OUTPUT WITH THIS SYSTEM BUT DID ELECT TO
RAISE POPS TO LIKELY ACROSS THE SOUTH/SOUTHEAST ZONES BY 12Z TUE.
SHOULD THE LATEST 00Z NAM RUN VERIFY...MUCH OF THE AREA WILL SEE
PRECIP BY 12Z TUE IN FACT. MAY AGAIN SEE A BRIEF PERIOD OF MOSTLY
SLEET WITH SOME FZRA ACROSS THE SOUTH AS THE PRECIP PUSHES IN WITH
TEMPS OF ABOUT 2C AT 725MB PROGGED ON MODEL POINT SOUNDINGS BUT
SHOULD CONTINUE TO TRANSITION TO ALL SNOW RELATIVELY QUICKLY DURING
THE MORNING TUE. QPF AMOUNTS RUNNING AROUND A QUARTER TO A THIRD OF
AN INCH...SO CERTAINLY SOME 1-2 INCH AMOUNTS WILL BE POSSIBLE.
ALSO...STILL A LONG WAY OUT TO TRY TO PIN DOWN MESOSCALE DETAIL. BUT
CONCEPTUALLY WITH STRONG JET STREAK JUST TO OUR NORTHWEST...AS WELL
AS PROGGED EPV/THETA-E LAPSE RATE VALUES...SOME POTENTIAL FOR
BANDING WITH SLANTWISE OR OUTRIGHT CONVECTION ABOVE THE COLD DOME
APPEARS POSSIBLE WHICH MAY SERVE TO ENHANCE SOME SNOWFALL RATES AND
AMOUNTS. THIS SYSTEM SHOULD BE A FAIRLY QUICK-HITTER HOWEVER...WITH
THE HIGHEST POPS ALREADY EXITING BY 18Z TUE WITH ONLY A SLIGHT
CHANCE OF LIGHT SNOW ONCE AGAIN ONLY IN THE EASTERN MOUNTAINS BY 21Z
TUE. CLOUD COVER SHOULD REMAIN FAIRLY EXTENSIVE FOR MOST OF WV ZONES
WITH PERHAPS SOME LATE-DAY BREAKS IN THE CLOUDS. WILL CONTINUE PREV
FCST TREND OF GOING A GOOD DISTANCE BELOW MOS GUIDE FOR MAX TEMPS TUE.
WITH PRECIP PUSHING IN DURING THE MORNING HOURS WITH NO WARM
ADVECTION OR SUN TIL LATE IN THE DAY...DON/T FORESEE MUCH IN THE WAY
OF RECOVERY OF TEMPS FROM EARLY MORNING LOWS. THERE MAY BE A BIT
MORE RECOVERY ACROSS THE SE OHIO ZONES WHERE CLOUDS MAY BREAK A BIT
EARLIER IN THE DAY.

BY TUESDAY EVENING CLOUDS WILL RAPIDLY SCATTER AND CLEAR OUT AS SFC
HIGH PRESSURE NOSES IN FROM THE WEST. WITH HIGHS ONLY IN THE LOW TO
MID 30S AT BEST FOR THE LOWLANDS TUESDAY...CLEARING SKIES...AND
NEAR-CALM WINDS AFTER 06Z WED...STAGE WILL BE SET FOR A COLD NIGHT
WITH TEMPS DROPPING TO THE UPPER TEENS AND LOWER 20S FOR THE WV
LOWLANDS...AND ABOUT 10F-15F FOR THE FAR NW ZONES AND THE EASTERN
MOUNTAINS.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
JUST WHAT THE DOCTOR ORDERED.  A MOSTLY DRY PATTERN TUESDAY NIGHT
FRIDAY.  HAVE A SLIGHT CHANCE OF SOME LIGHT SNOW SHOWERS WEDNESDAY
NIGHT ACROSS THE NORTHERN WV MOUNTAINS.

DRY AIR AND THE LONG DECEMBER NIGHTS YIELDS COLD DAWN TEMPERATURES.

WAY DOWN THE ROAD...MOISTURE INCREASES FRIDAY INTO SATURDAY...HAVE
SOME CHANCE POPS BY SATURDAY.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
MESSY AVIATION FORECAST TODAY WITH LOTS OF IFR CIGS...BUT MVFR TO
VFR BEGINNING TO TAKE HOLD IN DOWNSLOPE REGIONS. ALSO HAVE MIXED BAG
OF PRECIP ONGOING. WARMER AIR IS MOVING IN...TRANSITIONING SNOW TO
SLEET AND THEN RAIN. SURFACE TEMPS ARE GRADUALLY CLIMBING ABOVE
FREEZING...SO A PERIOD OF FREEZING RAIN BEFORE SURFACE TEMPS CLIMB
ABOVE 32F WITH COLD RAIN. BKW WILL HOWEVER REMAIN BELOW FREEZING IN
SE FLOW...SO CONTINUE FREEZING RAIN THERE INTO THIS EVENING...THEN
TRANSITION TO RAIN.

ADDITIONAL MOISTURE ARRIVES TONIGHT...WITH CEILINGS AND VISIBILITIES
DROPPING BACK INTO IFR IN RAIN AND FOG.

FLOW TURNS FROM EAST TO SOUTHEAST TODAY AND WILL BE A BIT GUSTY IN
THE MOUNTAINS. THEN FLOW TURNS MORE S TO SW BY MONDAY MORNING.

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

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: TIMING OF CATEGORY AND P-TYPE CHANGES 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    H    H    H    M    M    M    H    H    H    H
HTS CONSISTENCY  M    M    H    H    H    H    H    H    H    M    H    H
BKW CONSISTENCY  L    L    L    H    H    H    M    M    M    H    H    H
EKN CONSISTENCY  L    H    H    H    H    H    H    H    H    H    H    H
PKB CONSISTENCY  H    M    H    M    M    H    H    H    H    H    H    H
CKB CONSISTENCY  L    L    H    H    H    H    H    M    H    H    H    H

AFTER 18Z MONDAY...
IFR POSSIBLE IN SNOW MONDAY NIGHT INTO TUESDAY IN.
-- End Changed Discussion --

&&

.HYDROLOGY...
-- Changed Discussion --
HAVE FLOOD WATCH FOR MUCH OF THE WV LOWLANDS AND
INTO NE KY AS MORE RAINFALL IS EXPECTED INTO TONIGHT...WHICH MAY
CAUSE ADDITIONAL RISES ON RIVERS. THIS ADDITIONAL RAIN MAY ALSO
CAUSE FLOODING ALONG SMALL CREEKS AND STREAMS. WILL NEED TO
MONITOR TRENDS TONIGHT FOR WHERE BAND OF HEAVIEST PRECIPITATION
SETS UP...AND THUS WHERE AREA OF HIGHEST CONCERN IS.
-- End Changed Discussion --

&&

.EQUIPMENT...
ADDITIONAL PARTS FOR PARKERSBURG ASOS ARE EXPECTED TO ARRIVE MONDAY.
AUTOMATED OBSERVATIONS WILL BE UNAVAILABLE AT TIMES UNTIL THEN.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
WV...FLOOD WATCH THROUGH MONDAY AFTERNOON FOR WVZ005-006-013>016-
     018-020-024>032-037>040.
     WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR WVZ035-
     036.
     WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR
     WVZ009>011-019-020-031-032-037-038.
     WINTER STORM WARNING UNTIL 4 AM EST MONDAY FOR WVZ046-047.
OH...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR OHZ066-
     067-075-076-083>087.
KY...FLOOD WATCH THROUGH MONDAY AFTERNOON FOR KYZ105.
     WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR
     KYZ101>103.
VA...NONE.
-- End Changed Discussion --

&&

$$
SYNOPSIS...KTB/MZ/50
NEAR TERM...MZ
SHORT TERM...50
LONG TERM...KTB
AVIATION...MZ
HYDROLOGY...MZ
EQUIPMENT...MZ