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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 101153 AAA
AFDRNK

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BLACKSBURG VA
653 AM EST WED FEB 10 2010

.SYNOPSIS...
LOW PRESSURE WILL INTENSIFY OFF THE MID ATLANTIC COAST TODAY AND
THEN SLOWLY LIFT NORTHEAST AND AWAY FROM THE AREA LATER TONIGHT. A
STRONG ARCTIC COLD FRONT TRAILING THIS SYSTEM WILL USHER IN VERY
STRONG WINDS AND COLD TEMPERATURES INTO THURSDAY. THIS IN
COMBINATION WITH RESIDUAL MOISTURE AND NORTHWEST FLOW WILL ALSO
RESULT IN WIDESPREAD SNOW SHOWERS ACROSS THE MOUNTAINS.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
SENDING A QUICK UPDATE TO DROP THE GOING WINTER WX ADVISORY FROM
THE NEW RIVER VALLEY AND POINTS EAST GIVEN CLEARING SKIES AND
DOWNSLOPING. EXPECT WILL SEE SOME ADDED SNOW SHOWERS REDEVELOP
FROM THE ROA VALLEY WEST THIS MORNING BUT NOT ENOUGH ACCUMULATION
TO KEEP AN ADVISORY GOING AT THIS POINT. ALSO ADDING ALLEGHANY
COUNTY VA TO THE WINTER WX ADVISORY THAT RUNS THRU LATE TONIGHT
GIVEN STRENGTH OF UPSLOPE FLOW. PREVIOUS DISCUSSION BELOW...

ARCTIC FRONT NOW CROSSING THE BLUE RIDGE WILL CONTINUE TO WORK
EAST BRINGING A SUDDEN INCREASE IN WINDS ALONG WITH FALLING TEMPS
AND A QUICK SHOT OF HEAVIER SNOWFALL THRU DAYBREAK. THUS EXTENDING
THE GOING ADVISORY IN SPOTS THRU NOON TO COVER THIS AND QUICK
FREEZING OF MOISTURE WHERE -SN PERSIST ALONG 460 EARLY ON. THEN AS
THE COASTAL STARTS TO DEEPEN LATER THIS MORNING...GOOD NW
TRAJECTORY OF UPSLOPE SNOWFALL SHOULD CRANK INTO GEAR AND PERSIST
INTO TONIGHT. WITH MOISTURE DEPTH GOOD AND UNIFORM NW
FLOW...INCLUDING SPEED SHEAR WITH HEIGHT THRU A LAYER OF
DEVELOPING INSTABILITY...EXPECT HEAVIER SNOW SQUALLS AND BANDS TO
BECOME QUITE WIDESPREAD BY AFTERNOON ACROSS THE WEST. THINKING UP
TO A FOOT POSSIBLE ACROSS WESTERN GREENBRIER THRU TONIGHT WITH
WARNING CRITERIA ALL ALONG THE WESTERN SLOPES WHERE WILL ADD A
COUPLE MORE COUNTIES TO THE WARNING. STEEP LAPSES UNDER THE COLD
POOL SHOULD ALSO ALLOW ACCUMULATING SNOW TO WORK FARTHER EAST SO
INCLUDING ANOTHER LAYER OF COUNTIES ACROSS THE WEST IN AN ADVISORY
THRU LATE TONIGHT. WARNING MAY NEED TO GO LONGER INTO THU BUT DEEP
RH ON THE WANE BY THEN SO WILL HOLD OFF FOR NOW. ALSO CONSIDERED A
BLIZZARD WARNING FOR PARTS OF THE WESTERN SLOPES GIVEN STRONG
WINDS AND BLOWING SNOW ALTHO THINK VSBYS MAY ONLY DROP BELOW A 1/4
MILE AT TIMES IN SPOTS SO HELD OFF. OTRW CAT POPS WESTERN SLOPES
RANGING TO CHANCE JUST EAST OF THE BLUE RIDGE AND LITTLE ACROSS
THE PIEDMONT AFTER EARLY THIS MORNING. FALLING TEMPS IN ORDER
UNDER THE PASSING CORE OF -18C 85H COLD POOL THIS MORNING WITH
ONLY A SLIGHT REBOUND...AND OVERALL BELOW MOS THIS AFTERNOON.

BIGGEST ISSUE IS THE THREAT FOR WIDESPREAD WIND DAMAGE ESPCLY
LATER THIS AFTERNOON AS WE GET A FEW BREAKS AND MIXING ENHANCES
UNDER A LOWERING INVERSION. LATEST FCST RAOBS SHOW POTENTIAL FOR
THE HIGHER RIDGES TO SEE GUSTS IN EXCESS OF 70-75 MPH NW NC AND
60+ BLUE RIDGE. THINGS MAY NOT BE QUITE IN SYNC AS THE FEB 2008
EVENT REGARDING COLD ADVECTION...SUBSIDENCE AND JET DYNAMICS BUT
CLOSE ENOUGH ESPCLY IF LAPSES COME IN LINE WHEN THE 85H JET IS
STRONGEST LATER ON TO PRODUCE A DAMAGING EVENT. STRONGEST WINDS
WILL LIKELY PERSIST THRU MIDNIGHT AND THEN SLACKEN SOME BUT STILL
WARNING CRITERIA ON THE RIDGES THRU THU MORNING. OTRW TYPICAL
BREAK IN CLOUDS IN NW FLOW REGIME OVERNIGHT WITH CLOUDS/SNOW
SHOWERS WEST AND CLEARING EAST. TEMPS LIKELY TO BE STEADY OR RISE
SOME GIVEN MIXING AND STEADY STATE 85H VALUES.
-- End Changed Discussion --

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
UPSLOPE SNOW SHOWERS WILL CONTINUE THROUGH THURSDAY NIGHT ALONG THE
FAVORABLE WESTERN UPSLOPE AREAS IN SOUTHEAST WEST VIRGINIA SOUTH
THROUGH THE MOUNTAIN EMPIRE AND THE NORTHERN MOUNTAINS OF NORTH
CAROLINA. IT WILL BEGIN TAPERING OFF FROM SOUTH TO NORTH THROUGH THE
NIGHT THURSDAY. AN ADDITIONAL 2 INCHES OR LESS COULD ACCUMULATE
BEFORE ALL IS SAID AND DONE.

WINDS WILL SUBSIDE THROUGH LATE EVENING THURSDAY AS THE LOW LEVEL
JET DIMINISHES.

HIGH PRESSURE NOSES INTO THE AREA FROM THE WEST FRIDAY ENDING THE
UPSLOPE SNOW SHOWERS.

TEMPERATURES WILL REMAIN BELOW SEASONAL NORMS.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
ON FRIDAY...HIGH PRESSURE MOVES OVERHEAD AND BRINGS AN END TO THE
UPSLOPE SNOW SHOWERS IN THE WEST VIRGINIA MOUNTAINS. FRIDAY INTO
SATURDAY...AN AREA OF LOW PRESSURE WILL MOVE THROUGH THE GULF COAST
STATES WHERE ITS ASSOCIATED ENERGY AND PRECIPITATION WILL OCCUR.
ONLY THE UNPREFERRED GEM SOLUTION CONTINUES TO KEEP SOME LIGHT
PRECIPITATION ASSOCIATED WITH THE NORTHERN EXPANSE OF PRECIPITATION
ON THE NORTH SIDE OF THE LOW OVER OUR AREA. WE WILL CONTINUE WITH A
FORECAST THAT DOES NOT HAVE THIS SYSTEM IMPACT OUR REGION.

WHAT WILL HAVE A CHANCE TO IMPACT THE WEATHER FOR AT LEAST A
PORTION OF THE AREA...WILL BE A RETURN TO NORTHWEST UPSLOPE FLOW
INTO THE SE WV MOUNTAINS BY SATURDAY IN ADVANCE OF AN APPROACHING
SHORTWAVE SWINGING SOUTH OUT OF THE GREAT LAKES. GUIDANCE VARIES ON
THE TIMING AND MOISTURE CONTENT OF THIS SYSTEM. HAVE FAVORED THE
GUIDANCE OFFERED BY HPC THAT SUGGESTS THE BULK OF THE ENERGY AND
MOISTURE ASSOCIATED WITH THIS SYSTEM WILL BRING SCATTERED
PRECIPITATION...RAIN OR SNOW SHOWERS DEPENDING UP THE LOCAL
TEMPERATURE...TO A GREATER EXPANSE OF THE REGION ON SUNDAY. JUST
AHEAD...AND ESPECIALLY BEHIND THIS SYSTEM...A RETURN OF SNOW SHOWERS
IN THE SE WV MOUNTAINS SOUTH INTO THE NORTHERN MOUNTAINS OF NW NC IS
EXPECTED WITH A TREND TOWARDS DECREASING COVERAGE ON TUESDAY. HAVE
ALSO FAVORED TEMPERATURES IN LINE WITH GUIDANCE FROM HPC.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
FRONT NOW EXITING THE REGION WITH CLEARING SKIES EAST BUT WINDS
GUSTING 25-35 KTS ACROSS THE AREA. EXPECT THIS SCENARIO TO PREVAIL
TODAY WITH IMPROVING CONDITIONS TO VFR EAST AND IFR SE WVA WHERE
SNOW SHOWERS WILL BE ON THE INCREASE.

THE MAIN IMPACT IN THE TAFS WILL BE THE STRONG NW FLOW BEHIND THE
FRONT. A PROLONGED PERIOD OF NW WINDS OF 15 TO 30 KNOTS WITH GUSTS
AS HIGH AS 45 TO 55 KNOTS IS POSSIBLE AT TIMES THIS AFTERNOON INTO
EARLY TONIGHT. SEVERE TURBULENCE WILL BE THE RULE.

MVFR TO IFR CONDITIONS AND SNOW SHOWERS WILL OCCUR IN
BLF/LWB...ALONG WITH BLOWING SNOW TODAY INTO TONIGHT.

SHOULD SEE SOME IMPROVEMENT BY FRIDAY IN SE WVA AS HIGH PRESSURE
MOVES IN.

A CLIPPER SYSTEM ARRIVES SUNDAY AND COULD BRING SOME LOWER CIGS
INTO BLF/LWB AND EVEN ROANOKE. NW FLOW BEHIND THIS WILL KEEP SOME
POTENTIAL MVFR CIGS OR LOWER IN BLF/LWB EARLY NEXT WEEK WITH
MAINLY VFR ELSEWHERE.

&&

.EQUIPMENT...
MALFUNCTION OF THE NEW CEILOMETERS AT LYH...AND BLF HAS BEEN
REPORTED BY NATIONAL WEATHER SERVICE EASTERN REGION. THE CEILING
AT BLF IS NOW BEING REPORTED...AND APPEARS IN LINE WITH
SURROUNDING OBSERVATIONS. IF A DISCREPANCY IS NOTED...THE
CEILOMETER WILL NEED TO BE LOGGED OUT AGAIN. THE CEILING AT LYH
MAY NOT BE REPRESENTATIVE DURING THE OVERNIGHT HOURS WHEN THE
CONTROL TOWER IS CLOSED.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
VA...HIGH WIND WARNING UNTIL 5 AM EST THURSDAY FOR VAZ007-009>014-
     016>020-022>024-032>035-043>047-058-059.
     WINTER WEATHER ADVISORY UNTIL 6 AM EST THURSDAY FOR VAZ010>012-
     019-020.
     HIGH WIND WARNING UNTIL 1 PM EST THURSDAY FOR VAZ015.
     WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR VAZ007-009-
     015.
NC...HIGH WIND WARNING UNTIL 5 AM EST THURSDAY FOR NCZ003>006-019-
     020.
     WINTER WEATHER ADVISORY UNTIL 6 AM EST THURSDAY FOR NCZ002.
     HIGH WIND WARNING UNTIL 1 PM EST THURSDAY FOR NCZ001-002-018.
     WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR NCZ001-018.
WV...HIGH WIND WARNING UNTIL 5 AM EST THURSDAY FOR WVZ042>045.
     WINTER WEATHER ADVISORY UNTIL 6 AM EST THURSDAY FOR WVZ044.
     WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR WVZ042-043-
     045.
-- End Changed Discussion --

&&

$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...REB
LONG TERM...DS
AVIATION...AMS/JH/WP
EQUIPMENT...