-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 051745
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
1245 PM EST THU DEC 5 2013

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

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
1230 PM UPDATE...BUMPED UP TODAYS TEMPS ANOTHER DEGREE OR TWO
BASED ON CURRENT OBS.

PREVIOUS DISCUSSION BELOW...

VERY INTERESTING RIDGE/VALLEY SPLITS REGARDING TEMPS BEING
OBSERVED ACROSS THE AREA. SOME 20 TO 25 DEGREE SPREADS BETWEEN
SOME OF THE SHELTERED VALLEYS AND HOLLOW VERSUS THE
HILLTOPS...SOME OF WHICH JUST A FEW MILES APART LOCATION WISE.
AREAS THAT HAVE INDEED DECOUPLED SHOULD BEGIN TO FEEL THE EFFECTS
OF STOUT LOW LEVEL JET THRU PREDAWN WITH RISING TEMPS. SOME OF THE
OBSERVING SITES WHO HAVE KEPT THE PUFF ALL NIGHT WILL STAY IN THE
UPPER 50S TO AROUND 60...KHTS IS STILL 62F AS OF 07Z.

MUCH OF THE LOWER CLOUDS HAVE STAYED OFF TO THE WEST AND ALSO
ACROSS VA THUS FAR...WITH INFLUX OF HIGH CLOUDS THROUGH MORNING.
HAVE THE COLD FRONT CROSSING INTO SE OH AFTER 15Z AND VERY SLOWLY
PUSHING E INTO C WV AFTER BETWEEN 22Z AND 00Z. HAVE IT CLEARING
THE MOUNTAINS BY 06Z BEFORE PUTTING THE BREAKS ON AND STALLING
OUT. MUCH OF THE PRECIP WITH THIS WILL BE ALONG AND ESPECIALLY
BEHIND THE SURFACE BAROCLINIC ZONE AS THE BOUNDARY ALOFT LAGS
BEHIND. GIVEN THE FRONTAL TIMING AND RESIDUAL SE LOW LEVEL
FLOW...THINK BULK OF THE PRECIP WILL STAY ALONG AND ESPECIALLY W
OF THE OH RIVER MORE INTO SE OH THRU MUCH OF THE DAY. AS SUCH SLOW
TO ADVANCE THE POPS E TODAY. BROAD SW FLOW WILL CONT ABOVE H85
WITH SEVERAL WAVES THIS AFTERNOON AND TONIGHT ON GOOD
FRONTOGENETIC FORCING AND MID LEVEL DEFORMATION. THIS COMBINED
WITH EVENTUAL PASSAGE OF SURFACE FRONT WILL ALLOW RAINS TO
OVERSPREAD THE REMAINDER OF THE AREA TONIGHT. ENOUGH LOW LEVEL
COLD AIR WILL HAVE FILTERED IN BY 12Z FOR A CHANGEOVER TO SLEET
ACROSS PERRY AND MORGAN...WITH A RAIN SLEET MIXTURE DOWN INTO
ATHENS/VINTON. NOT EXPECTING MUCH IN THE WAY OF ANY ACCUMULATIONS
BY 12Z.

GUSTY WINDS ON THE HIGHER HILLTOPS AND MOUNTAIN RIDGES FROM LOW
LEVEL JET WILL SUBSIDE SOME TODAY. STILL HAVE A GOOD PUFF ACROSS
SE OH TODAY.

FOR TEMPS...HARD TO BELIEVE THE 76F THE MET MOS IS SPITTING OUT
FOR CRW TODAY AS WELL AS SOME OF THE OTHER NUMBERS IT HAS OTHER
LOCATIONS. HAVING SAID THAT...THINK MAV IS TOO COOL ACROSS WV/SW
VA AND FELT IN HOUSE LOCAL MOS WAS A GOOD COMPROMISE. THIS MEANS
UPPER 60S ACROSS THE WV LOWLANDS WITH A SHOT AT 70F IN THE COAL
FIELDS. HAVE LOWER 60S IN SE OH WITH PERHAPS DROPPING IN THE
AFTERNOON INTO THE 40S. FOR TONIGHT...USED SOME OF THE RAW NUMBERS
OFF THE NAM/GFS TO FOLLOW PROGRESSION OF THE FRONT WITH SE OH
DIPPING DOWN INTO THE 30S TONIGHT WHILE THE MOUNTAINS REMAIN ON
THE MILD SIDE THRU 12Z. NW PORTIONS OF PERRY CO MAY DIP CLOSE TO
FREEZING AT 12Z.

QPF TOTALS THROUGH NEAR TERM WILL BE HIGHEST ACROSS SE OH/NE KY WHERE
UP TO AN INCH AND HALF MAY FALL. FURTHER E...AMOUNTS TAPER OFF
QUICKLY TO AROUND HALF AN INCH TOWARD I79 CORRIDOR.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
MODELS CONTINUE TO BE FAIRLY CONSISTENT WITH THE SYSTEM FOR FRIDAY
AND FRIDAY NIGHT. BIG CONCERNS ARE THE AMOUNT OF RAINFALL EXPECTED
AND A POSSIBLE SLEET SITUATION IN PORTIONS OF SOUTHEAST OHIO. THE
MODELS CONSISTENTLY ARE PRODUCING A BAND OF 2 TO 2.5 INCHES. A FLASH
FLOOD WATCH REMAINS IN EFFECT WEST OF THE MOUNTAINS. ALL MODELS ARE
ALSO SHOWING SLEET SOUNDINGS FROM ATHENS NORTHWESTWARD ON FRIDAY. WILL
HAVE TO WATCH THIS CLOSELY ON FUTURE MODEL RUNS...AS CURRENT MODELS
SHOWING SEVERAL INCHES OF SLEET ARE POSSIBLE IN THIS AREA.

NEXT SYSTEM ARRIVES LATE SATURDAY NIGHT...AND IS A LITTLE SLOWER
THAN PREVIOUS RUNS. WILL ADJUST THE ONSET OF PRECIPITATION SLIGHTLY.
WITH RIVERS RUNNING HIGH FROM FIRST EVENT...THERE IS A THREAT OF
FLOODING WITH THIS SYSTEM AS WELL. MODELS ARE GENERALLY SHOWING THE
HEAVIEST BAND OF PRECIPITATION BEING SOUTH OF FIRST SYSTEM...BUT
RAINFALL AMOUNTS OF 1 TO 2 INCHES SO QUICK AFTER THE FIRST SYSTEM IS
VERY WORRISOME.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
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.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --
AREA OF MAX PRECIP ROUGHLY ALONG THE OHIO RIVER WITH SOME MVFR
VSBY/CIG. THIS IS AHEAD OF A COLD FRONT CURRENTLY ENTERING EXTREME
WESTERN CWA. EXPECT THIS MVFR TO GRADUALLY SPREAD EASTWARD THROUGH
THE REST OF TODAY AS THE COLD FRONT MOVES VERY SLOWLY EASTWARD.
STILL SOME CONVECTIVE NATURE TO THE RAIN...AND COULD GET BRIEF
DROPS INTO IFR VISIBILITIES THIS AFTERNOON. CEILINGS WILL CONTINUE
TO DROP TONIGHT...WITH IFR EXPECTED ACROSS MUCH OF THE CWA...WHILE
MVFR VISIBILITIES CONTINUE IN RAIN.

HAVE SW WINDS TODAY...WITH SOME GUSTS OF 15-20KTS. AS A COLD FRONT
PASSES...WILL SEE WINDS GO MORE NW THEN N. HOWEVER...SEVERAL
WAVES MAY CAUSE SOME DIVERGENCE FROM THIS GENERAL FLOW AS THEY
LIFT ALONG THE FRONT.

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

FORECAST CONFIDENCE: MEDIUM TO HIGH.

ALTERNATE SCENARIOS: ONSET OF LOWER CIGS/VSBYS AHEAD OF COLD
FRONT THU MAY VARY. MAY NEED TEMPOS THIS AFTERNOON FOR CONVECTIVE
ENHANCED SHOWERS PRODUCING IFR VIS.

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       18   19   20   21   22   23   00   01   02   03   04   05
EST 1HRLY       13   14   15   16   17   18   19   20   21   22   23   00
CRW CONSISTENCY  H    H    M    M    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    M    H    H    H    H
EKN CONSISTENCY  H    H    H    H    H    H    M    H    H    H    L    L
PKB CONSISTENCY  H    H    H    M    M    H    H    H    H    M    H    H
CKB CONSISTENCY  H    H    M    M    H    H    H    H    H    H    H    H

AFTER 18Z FRIDAY...
IFR POSSIBLE RAIN OR SNOW/SLEET FRIDAY NIGHT. IFR POSSIBLE AGAIN
SUNDAY AND MONDAY.
-- End Changed Discussion --

&&

.HYDROLOGY...
-- Changed Discussion --
SIGNIFICANT RISES ARE EXPECTED ON RIVERS IN RESPONSE TO
ONGOING...PROLONGED RAIN WHICH IS EXPECTED TO LAST INTO FRIDAY
NIGHT. RIVERS THAT ARE ESPECIALLY VULNERABLE INCLUDE BUT ARE NOT
LIMITED TO... THE LITTLE SANDY INCLUDING GRAYSON...THE WEST FORK
INCLUDING CLARKSBURG...THE LITTLE KANAWHA...MUD...POCATALICO...THE
TYGART VALLEY...AND SYMMES CREEK. RISES ARE ALSO EXPECTED ON SMALL
CREEKS AND STREAMS THAT DRAIN INTO THESE LARGER...MAIN STEM
WATERWAYS.

ANOTHER WET SYSTEM WILL EFFECT THE REGION ON SUNDAY AND MONDAY. WITH
THE RIVERS ALREADY RUNNING HIGH FROM THE CURRENT EVENT...THE
THREAT OF RIVER FLOODING INCREASES EVEN MORE.
-- End Changed Discussion --

&&

.EQUIPMENT...
-- Changed Discussion --
AUTOMATIC OBSERVATIONS REMAIN MISSING FOR PARKERSBURG DUE TO AN
EQUIPMENT FAILURE. PARTS ARE ON ORDER AND ARE EXPECTED TO
ARRIVE...POSSIBLY AS EARLY AS TODAY.
-- End Changed Discussion --

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLOOD WATCH FROM 7 PM EST THIS EVENING THROUGH SATURDAY
     MORNING FOR WVZ005>011-013>020-024>032-039-040.
OH...FLOOD WATCH FROM 7 PM EST THIS EVENING THROUGH SATURDAY
     MORNING FOR OHZ066-067-075-076-083>087.
KY...FLOOD WATCH FROM 7 PM EST THIS EVENING THROUGH SATURDAY
     MORNING FOR KYZ101>103-105.
VA...NONE.

&&

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