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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 100008
AFDRLX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
708 PM EST TUE FEB 9 2010

.SYNOPSIS...
-- Changed Discussion --
ARCTIC FRONT BLOWS THROUGH THIS EVENING. MUCH COLDER AND BRISK WITH
SNOW SHOWERS THROUGH WEDNESDAY NIGHT. UPSLOPE SNOW SHOWERS LINGER
INTO THURSDAY FOR MOUNTAINS. COLD PATTERN CONTINUES INTO NEXT WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
DEEP COMPACT AND VERY COLD UPPER LOW IS INBOUND...WITH ITS
ASSOCIATED TROPOPAUSE FOLD NEAR SAINT LOUIS IN THE NAM ALL THE WAY
DOWN TO ABOUT 800MB! THE UPPER LOW IS SET TO PASS OVERHEAD BY
12Z...WITH 1000-500MB THICKNESSES SLIPPING BELOW 510 DECAMETERS.

WARM WEDGE AHEAD OF THE LOW CHANGED ALMOST ALL WINTRY MIX TO PLAIN
RAIN LATE MORNING THROUGH EARLY AFTERNOON. AS OF 3PM...WITH SURFACE
LOW LIFTING NORTHWARD INTO CENTRAL OHIO...ARCTIC FRONT IS KNOCKING
ON OUR WESTERN DOOR AND READY TO SWING THROUGH. FRONT WILL BE CLEAR
OF THE AREA BY AROUND 03Z. LOOKING AT ABRUPT DROP IN TEMPERATURES
BEHIND FRONT...WITH A FLASH FREEZE OF ANY WET SURFACES THIS EVENING.
ALSO...IMMEDIATELY ALONG FRONT...LOOKING AT RAIN SWITCHING TO SNOW
BEFORE LULL IN ACTIVITY FOR MUCH OF OVERNIGHT /FLURRIES OR SCATTERED
SNOW SHOWERS/ AS VERY LOW DEWPOINTS ADVECT INTO THE REGION.
THEN...DURING THE PREDAWN HOURS...WRAP AROUND MOISTURE QUICKLY
BRINGS ACCUMULATING WIND SWEPT SNOW SHOWERS ACROSS THE WESTERN TO
CENTRAL LOWLANDS...WITH THE REST OF THE AREA TO FOLLOW. WIND CHILLS
IN SINGLE DIGITS FOR MUCH OF THE AREA AT DAWN.

ONGOING WINTER STORM WARNING WILL CONTINUE THROUGH THE NEAR TERM
PERIOD...THOUGH WESTERN PORTION OF THE WARNING WILL END UP WITH LESS
SNOW COMPARED TO THE EASTERN PORTION /WV MOUNTAINS/. ALSO...AREA
THAT GOT ESPECIALLY WARM WEDGED WITH RAIN TODAY IN THE
LOWLANDS...WILL KEEP THE ADVISORY WITH LESS TOTAL SNOW WHEN
INCLUDING WHAT HAPPENED EARLIER TODAY. ALSO...WIND ADVISORY IN THE
MOUNTAINS...WAS BACKED UP TO A START TIME OF 05Z...WITH INCREASING
WINDS STARTING EARLIER DUE TO STRONG COLD AIR ADVECTION.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
THE COMPLEX WEATHER SYSTEM CONTINUES TO AFFECT OUR AREA THIS
PERIOD. MODELS ARE IN VERY GOOD AGREEMENT ON THE PROGRESSIVE VERY
STRONG AND COLD UPPER LOW DRIVING AN ARCTIC FRONT ACROSS THE AREA
TONIGHT...FOLLOWED BY A UNIQUE WARM ADVECTION SNOW EVENT LATE
TONIGHT AND WEDNESDAY.

FIRST...A PSEUDO COLD FRONT MOVES ACROSS THIS EVENING...AHEAD OF A
SOUTHERN STREAM UPPER TROUGH THAT LIFTED OUT AHEAD OF THIS UPPER
LOW...AND EFFECTIVELY ENDING MOST OF OUR PRECIPITATION THIS EVENING.
MOST OF THE PRECIP WAS LIGHT AND MAINLY IN THE FORM OF RAIN THIS
AFTERNOON...EXCEPT OVER PARTS OF SOUTHEAST OHIO AND HIGHER WEST
VIRGINIA MOUNTAIN ELEVATIONS. MOST TEMPERATURES WILL REMAIN CLOSE TO
OR JUST ABOVE FREEZING BEFORE THE ARCTIC FRONT PASSES A BIT LATER
TONIGHT.

THERE WILL BE A RELATIVE LULL IN THE PRECIP EARLY TONIGHT...UNTIL
DEEP MOIST WRAPAROUND NORTHWEST FLOW WITH THE UPPER LOW OVERSPREADS
OUR AREA LATER TONIGHT AND WEDNESDAY. THIS IS A UNIQUE
PATTERN WHERE MOST OF OUR PRECIP LATER TONIGHT AND WEDNESDAY WILL BE
WARM ADVECTION SNOW...WITH ATLANTIC MARITIME AIR BEING DRAWN ALL
THE WAY AROUND THIS UPPER LOW. THIS SCENARIO WILL BRING ABOUT A MORE
WIDESPREAD SNOW IN THIS WARM ADVECTION NORTHWEST FLOW. THIS MAY
SOMEWHAT LIMIT LOCALIZED HEAVY BANDS OF SNOW THAT WE COMMONLY FIND
IN COLD ADVECTION NORTHWEST UPSLOPE FLOW AND PLUMES OFF THE LAKES.
NEVERTHELESS...SIGNIFICANT ACCUMULATIONS OF SNOW ARE EXPECTED ACROSS
THE AREA THROUGH WEDNESDAY...AND INTO WEDNESDAY IN THE NORTHERN
MOUNTAINS. DESPITE LACK OF STRONG COLD ADVECTION...THE MOUNTAINS
WILL STILL SEE ENHANCED UPSLOPE SNOWS WITH IDEAL NORTHWEST FLOW.
GUSTY WINDS WILL ALSO CAUSE SOME BLOWING AND DRIFTING OF THE
SNOW...ESPECIALLY IN THE MOUNTAINS WHERE WIND ADVISORIES WILL BE IN
EFFECT LATER TONIGHT AND WEDNESDAY. THUS...WINTER STORM WARNINGS AND
ADVISORIES WILL ALSO REMAIN IN EFFECT. HOWEVER...NO WIND CHILL
ADVISORY...AS CRITERIA NOT MET OUTSIDE THE HIGHEST ELEVATIONS.

TEMPS WILL BE TRICKY...WITH THE WARM ADVECTION PATTERN WEDNESDAY. SO
AFTER TEMPS TAKE A FALL BEHIND THE ARCTIC FRONT TONIGHT...WE LOOK
FOR SOME TEMPERATURE RECOVERY WEDNESDAY...BUT WILL REMAIN BELOW
FREEZING.  GOING ON THE LOWE SIDE OF GUIDANCE.

HIGH PRESSURE BUILDS IN WEDNESDAY NIGHT AND THURSDAY...WITH SNOW AND
SNOW SHOWERS DIMINISHING...LEADING TO QUITE COLD TEMPERATURES ONCE
AGAIN.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
BASED ON 850 MB TEMPERATURES AND LOW LEVEL MOISTURE...WILL LINGER A
FEW SNOW SHOWERS IN THE NORTHERN MOUNTAINS FOR FRIDAY MORNING.
MODELS SHOW THE COLD PATTERN HOLDING THROUGH THE WEEKEND AND INTO
NEXT WEEK. WHILE THERE IS GOOD AGREEMENT ON THE GENERAL COLD
PATTERN...CONFIDENCE IN THE DETAILS AND TIMING OF PRECIPITATION
IMPULSES IS LOW.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
LOW PRESSURE SYSTEM TO CAUSE COMPLICATED DEGRADED CONDITIONS THROUGH
18Z WEDNESDAY. WARM AIR SURGE AHEAD OF THE INBOUND LOW PRESSURE
BRINGING VARIABLE CONDITIONS IN RAIN AND PATCHY DENSE VALLEY FOG /
WARM AIR OVER SNOW COVER/ IN S FLOW AHEAD OF ARCTIC FRONT.

ARCTIC FRONT BLOWING THROUGH CRW RIGHT AT START OF PERIOD...HAVING
JUST PAST HTS AND WILL ACROSS EKN NEAR 05-06Z AND THROUGH THE ARE
ENTIRELY SHORTLY AFTER THAT.  THIS WILL CLEAN OUT THE FOG BUT BRIEF
IFR LIKELY IN SNOW SHOWERS IMMEDIATELY BEHIND THE FRONT.  WIND
SHIFTS TO WSW BAND BECOME GUSTY BEHIND THE FRONT.

SOMEWHAT OF A LULL OCCURS OVERNIGHT...BEFORE WRAP AROUND MOISTURE
BRINGS IN GUSTY SNOW SHOWERS WEDNESDAY MORNING. GENERAL MVFR WITH
TIMES OF IFR EXPECTED IN THE SNOW SHOWERS...BUT BLOWING SNOW MAY
BRING IT DOWN TO WORSE THAN IFR AT TIMES IN THE HEAVIER SNOW BANDS.
THE SNOW SHOWERS MAY DIMINISH SOMEWHAT IN THE AFTERNOON...BUT
BLOWING SNOW WILL CONTINUE TO RESTRICT VSBY AT TIMES AS CIGS STAY NO
BETTER THAN MVFR.

AFTER 00Z THURSDAY...
INTERMITTENT IFR OR WORSE CONDITIONS EXPECTED IN BANDS OF SNOW
SHOWERS THROUGH WEDNESDAY NIGHT...ESPECIALLY IN THE
MOUNTAINS...WHERE IT MAY LAST WELL INTO THURSDAY MORNING.
-- End Changed Discussion --

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR WVZ005>007-
     009>011-017>020-027>032-035>040-046-047.
     WIND ADVISORY FROM MIDNIGHT TONIGHT TO 4 AM EST THURSDAY FOR
     WVZ033>038-046-047.
     WINTER WEATHER ADVISORY UNTIL 7 AM EST THURSDAY FOR WVZ008-
     013>016-024>026-033-034.
OH...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR OHZ066-067-
     075-076-083>087.
KY...WINTER STORM WARNING UNTIL 7 AM EST THURSDAY FOR KYZ101>103-
     105.
VA...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 4 AM EST THURSDAY FOR
     VAZ003-004.
     WINTER WEATHER ADVISORY UNTIL 7 AM EST THURSDAY FOR VAZ003-004.

&&

$$
SYNOPSIS...MDP/JMV/RPY
NEAR TERM...MDP
SHORT TERM...JMV
LONG TERM...RPY
AVIATION...TRM