-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 090555
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1255 AM EST MON DEC 9 2013

.SYNOPSIS...
WARM FRONT LIFTS NORTH INTO TONIGHT.  A LOW PRESSURE WAVE CROSSES
LATER TONIGHT INTO MONDAY.  A WEAK SYSTEM CROSSES LATE MONDAY NIGHT
INTO TUESDAY. CHILLY DRY HIGH PRESSURE FOR WEDNESDAY INTO FRIDAY.

&&

.NEAR TERM /THROUGH TODAY/...
8 PM...EXPANDED FLOOD WATCH ACROSS SOUTHWEST VA AND SOUTHERN COAL
FIELDS AS SOME DECENT PRECIPITATION AMOUNTS...0.5 TO 0.75 INCHES
IN AN HOUR AT A FEW SPOTS...ARE BEING REALIZED.

PREVIOUS DISCUSSION...
SECONDARY WAVE AND ASSOCIATED PRECIPITATION STARTING TO PUSH INTO
THE CWA THIS EVENING. FOR NOW...TAKING A WATCHFUL APPROACH
CONCERNING EXPANDING A FLOOD WATCH ACROSS SOUTHERN COAL FIELDS AND
SOUTHWEST VA. SO FAR...GENERALLY 0.1 TO 0.15 INCHES OF
PRECIPITATION OBSERVED FROM BAND IN AN HOUR. FFG IN THESE AREAS IS
AVERAGING ABOUT 1.15 INCHES IN 3 HOURS. IN ADDITION...THIS IS AN
AREA THAT RECEIVED LESS RAINFALL THAN THE REMAINDER OF THE CWA A
FEW DAYS AGO. IF HIGHER RAINFALL RATES ARE OBSERVED...WILL ISSUE A
WATCH. MOST OF THE PRECIPITATION FROM THIS WAVE IS EXPECTED
REMAIN GENERALLY ALONG AND EAST OF THE I79 CORRIDOR.

TEMPERATURES ARE STRUGGLING TO WARM ALONG THE MOUNTAINS...WHERE
COLD AIR CONTINUES TO REMAIN TRAPPED ALONG EASTERN SLOPES. DID
ELECT TO EXTEND THE ADVISORY FOR NICHOLAS AND WEBSTER UNTIL
05Z...AND EXTEND THE WARNING FOR RALEIGH AND FAYETTE COUNTIES
UNTIL 05Z. ALSO DECIDED TO EXTEND THE WARNING FOR RANDOLPH AND
POCAHONTAS COUNTIES UNTIL 12Z BASED ON LATEST MODEL RUNS WHICH
SUGGEST FZRA COULD OCCUR WELL INTO MONDAY MORNING. DID CANCEL THE
ADVISORY ACROSS OHIO AND ADJACENT WV COUNTIES THIS EVENING.


PREVIOUS DISCUSSION FOLLOWS...
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.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
UPPER LEVEL SW FLOW FINALLY FLATTENS...BECOMING MORE ZONAL...IN THE
WAKE OF A S/W TROUGH THAT CROSSES TUE.  SYSTEM IN THE NEAR TERM IS
ABOUT EXODUS BY 00Z TUE...THE START OF THE SHORT TERM...WITH PERHAPS
LIGHT UPSLOPE PRECIPITATION WINDING DOWN.  WHILE NOT AS MOISTURE
RICH AS PREVIOUS SYSTEMS...JET DYNAMICS AND S/W FORCING IN THE
BAROCLINIC ZONE SHOULD GENERATE A QUICK HITTING BAND OF
PRECIPITATION THROUGH THE MIDDLE OHIO VALLEY EARLY TUE MORNING.
ANOTHER BAND BRUSHES THE CENTRAL APPALACHIANS AS A SFC WAVE MOVES NE
ALONG THE FRONT WHICH WILL BE OVER THE CAROLINAS AT THAT TIME.

COLDER AIR MOVING IN MON NT WILL DRIVE H85 TEMPERATURES TO -6C TO
-10C N BY TUE AFTERNOON...SO THE PRECIPITATION WILL TAKE THE FORM OF
SNOW...SAVE FOR MIXED PRECIPITATION EARLY ON OVER THE CENTRAL
APPALACHIANS.

ANY UPSLOPE PRECIPITATION IN THE WAKE OF THIS EVENT TUE AFTERNOON IS
BRIEF...AND HIGH PRESSURE BUILDS IN FOR A DRY AND COLD TUE NT...AND
THEN HANGS ON FOR A DRY WED.

USED ADJMET AND NAM FOR TEMPERATURES IN COLD ADVECTION MON
NT...BLENDED IN ADJMET FOR HIGHS TUE AND BIAS CORRECTED ADJMET FOR
LOWS TUE NT.  BLENDED IN BIAS CORRECTED ADJMEX FOR HIGHS WED.
OVERALL NO MAJOR CHANGES.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
STILL JUST WHAT THE DOCTOR ORDERED.  A MOSTLY DRY PATTERN
WEDNESDAY NIGHT INTO SATURDAY.  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.

DOWN THE ROAD...MOISTURE INCREASES SATURDAY...HAVE SOME CHANCE POPS
BY SATURDAY FOR RAIN AND SNOW.  STILL APPEARS NOT A HEAVY EVENT.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
PERHAPS THE LAST BAND OF LIGHT RAIN UNDER 35 DEGREES MOVING
SLOWLY EAST THROUGH AT LEAST 09Z. THEN...AREAS OF RAIN ARE
EXPECTED TO EXIT THE EASTERN MOUNTAINS. HOWEVER...PERIODS OF
IFR/LIFR WILL BE COMMON UNDER AREAS OF RAIN. A LOW LEVEL DECK
AROUND 500 FEET IS EXPECTED TO FORM OR CONTINUE ACROSS MOST SITES
THROUGH THE PREDAWN HOURS.

AREAS OF LIFR CIGS DEVELOPING MAINLY 03Z THROUGH 14Z OVERNIGHT...LIFTING
TO IFR/MVFR FOR REMAINDER OF TAF PERIOD.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...

FORECAST CONFIDENCE: MEDIUM.

ALTERNATE SCENARIOS: TIMING OF IFR/LIFR CIGS MAY VARY FROM CURRENT FORECAST.

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.

DATE                                   MON 12/09/13
UTC 1HRLY       06   07   08   09   10   11   12   13   14   15   16   17
EST 1HRLY       01   02   03   04   05   06   07   08   09   10   11   12
CRW CONSISTENCY  M    M    H    H    M    M    M    M    M    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
BKW CONSISTENCY  M    M    H    H    M    M    M    H    H    M    H    M
EKN CONSISTENCY  M    M    M    M    M    M    M    M    M    M    M    L
PKB CONSISTENCY  H    H    M    H    H    H    H    H    L    L    L    H
CKB CONSISTENCY  M    H    H    M    M    M    M    M    H    M    M    M

AFTER 06Z TUESDAY...
IFR POSSIBLE IN SNOW MONDAY NIGHT INTO TUESDAY.
-- End Changed Discussion --

&&
.HYDROLOGY...
THE LAST OF THE RIVER FLOOD WARNINGS AT BELINGTON ASSOCIATED WITH
THE RAINFALL LAST THURSDAY AND FRIDAY...IS GONE.

HAVE FLOOD WATCH FOR MUCH OF THE WV LOWLANDS AND INTO NE KY AS MORE
RAINFALL IS EXPECTED TONIGHT INTO MONDAY...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 THE BAND OF HEAVIEST PRECIPITATION SETS UP...AND
THUS WHERE THE AREA OF HIGHEST CONCERN IS.

&&

.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 THIS AFTERNOON FOR WVZ005-006-013>016-018-
     020-024>040.
     WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR WVZ037-
     038.
     WINTER STORM WARNING UNTIL 7 AM EST THIS MORNING FOR WVZ035-
     036-046-047.
OH...NONE.
KY...FLOOD WATCH THROUGH THIS AFTERNOON FOR KYZ105.
VA...FLOOD WATCH THROUGH THIS AFTERNOON FOR VAZ003-004.
-- End Changed Discussion --

&&

$$
SYNOPSIS...KTB/TRM/MZ
NEAR TERM...ARJ/MZ/SL
SHORT TERM...TRM
LONG TERM...KTB
AVIATION...ARJ