Area Forecast Discussion
Issued by NWS Blacksburg, VA

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FXUS61 KRNK 262222
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
522 PM EST MON JAN 26 2015

.SYNOPSIS...
LOW PRESSURE OVER VIRGINIA WILL DEVELOP INTO A MAJOR WINTER STORM
AS IT MOVES NORTHEAST ALONG THE NEW ENGLAND COAST TONIGHT AND
TUESDAY. THIS STORM WILL INFLUENCE OUR WEATHER THROUGH TUESDAY
WITH MOUNTAIN SNOW SHOWERS AND GUSTY NORTHWEST WINDS.

&&

.NEAR TERM /THROUGH TUESDAY NIGHT/...
AS OF 430 PM EST MONDAY...

LOW PRESSURE IS CURRENTLY PASSING OVER CENTRAL VIRGINIA WITH
UPPER TROF AXIS AND COLDER AIR SPILLING OVER THE APPALACHIAN
MOUNTAINS. TEMPERATURES ARE FALLING ACROSS THE MOUNTAINS...AND
THIS COLD AIR ADVECTION WILL CAUSE FALLING TEMPERATURES FARTHER
EAST AS WE PROGRESS THROUGH THE EVENING. TEMPERATURES HAVE ALREADY
DROPPED INTO THE 20S IN THE MOUNTAINS. READINGS IN THE 40S WERE
FOUND OVER THE PIEDMONT OF NC AND INTO SOUTHSIDE VA...BUT THESE
NUMBERS WILL TAKE A TUMBLE TONIGHT.

THROUGH 4PM TODAY...LITTLE OR NO SNOW HAD ACCUMULATED ANYWHERE
WITHING THE CWA...WITH MAINLY A MIX OF RAIN/SNOW OVER THE
MOUNTAINS AND RAIN EAST OF THE BLUE RIDGE. AS TEMERATURES FALL
THIS EVENING...ANY LINGERING RAIN WILL CHANGE TO SNOW. THE
DEFORMATION ZONE ON THE NORTHWEST SIDE OF THE LOW IS EXPECTED TO
PRODUCE A PERIOD OF SNOW OVER THE MOUNTAINS THIS EVENING. HIGHEST
ACCUMULATIONS THIS EVENING ARE EXPECTED TO BE IN THE WV HIGHLANDS
WHERE 1 TO 3 INCHES OF ACCUMULATION IS ANTICIPATED BEFORE
MIDNIGHT. LATER TONIGHT THERE WILL BE A SECONDARY SURGE OF
MOISTURE ASSOCIATED WITH AN UPPER LEVEL SHORT WAVE CROSSING THE
NORTH CAROLINA MOUNTAINS. THIS WILL LIKELY RESULT IN ACCUMULATING
SNOW FOR THE NORTH CAROLINA HIGH COUNTRY AND MOUNT ROGERS IN
VIRGINIA. SNOW TO LIQUID RATIOS WILL ALSO BEGIN TO COME INTO PLAY
LATE TONIGHT AS TEMPERATURES DIP BELOW 20 DEG F...YEILDING 2 TO 1.
AS SUCH...THINK IT IS FEASIBLE TO SEE 2 TO 4 INCHES OF SNOW OVER
THE NC HIGH COUNTRY...POSSIBLY MORE AT ELEVATIONS ABOVE 4000 FT.

OVERALL THIS IS NOT EXPECTED TO BE A BIG SNOW PRODUCER FOR
THE CENTRAL APPALACHIANS. THE MAIN MEDIA FOCUS WILL BE ON COASTAL
NEW ENGLAND WHERE THIS AREA OF LOW PRESSURE WILL WRAP UP INTO A
MAJOR WINTER STORM. FOR THE CENTRAL APPALACHIANS...WE GET TO DEAL
WITH THE BACKLASH WINDS AND MOUNTAIN SNOW SHOWERS. THEIR IS SOME
POTENTIAL FOR WRAP AROUND MOISTURE FROM THE COASTAL STORM TO
PENETRATE AS FAR SOUTH AS OUR NORTHEASTERN CWA LATE TONIGHT...SO
WILL HAVE TO MONITOR THIS CLOSELY AS THERE MAY BE A NEED FOR
WINTER WEATHER HEADLINES FOR AREAS NORTHEAST OF LYNCHBURG...
SPECIFICALLY APPOMATTOX...BUCKINGHAM AND POINTS NORTH AND EAST.

EVEN THOUGH WE ARE NOT ADVERTISING MUCH PRECIP WITHIN OUR LOCAL
FORECAST AREA...THIS WEATHER SYSTEM IS VERY DYNAMIC...LOTS OF
ENERGY ALOFT THAT WILL CAUSE THIS STORM TO DEEPEN QUICKLY AS IT
MOVES UP THE EAST COAST. HAVE EVEN SEEN A FEW LIGHTNING STRIKES
WITHIN THE SHOWERS OVER THE NORTH CAROLINA PIEDMONT TODAY WHICH IS
AN INDICATOR OF HOW UNSTABLE THIS ATMOSPHERE IS BECOMING AND THE
POTENTIAL ENERGY THAT IS BUILDING UP FOR THIS THING TO FEED OFF OF
ONCE IT GETS EAST OF OUR FORECAST AREA AND CERTAINLY SETTING THE
STAGE FOR COASTAL BOMBOGENESIS TONIGHT. MODELS HAVE BEEN
STRUGGLING WITH QPF...AND IT WAS A BIT INTERESTING TO SEE ALL THE
QPF THE GFS MODEL PAINTING OVER OUR CWA THIS MORNING...YET NOT
MUCH WAS OCCURRING...CONVECTIVE FEEDBACK IN THE MODEL. WHAT REALLY
MADE IT HUMOROUS WAS THE MODEL THEN TOOK THE 4-6 TENTHS OF AN INCH
OF QPF AND CONVERTED IT TO ALL SNOW. ANYONE ISSUING FORECASTS AND
BLINDLY FOLLOWING GUIDANCE THIS MORNING WOULD HAVE THEN
EXPERIENCED A GOOD TASTE OF METEOROLOGICAL/MODEL CANCER...A
GARBAGE IN...GARBAGE OUT SORT OF FORECAST.

QPF ISSUES ASIDE...THE IMPACT FROM THIS STORM FOR OUR LOCAL AREA
WILL BE MINOR COMPARED TO OUR NEIGHBORS TO THE NORTH. I.E. NOTHING
WE HAVN`T SEE BEFORE. IN SUMMARY...A PERIOD OF SNOW IS LIKELY FOR
OUR MOUNTAINS TONIGHT WITH FLURRIES AND SCATTERED SNOW SHOWERS
LINGERING INTO TUESDAY. IT WILL BECOME BLUSTERY WITH NORTHWEST
WINDS OF 10 TO 20MPH...AND GUSTS OF 25 TO 30 MPH. A 40 MPH GUST
OVER THE NC/VA/WV HIGHLANDS IS CERTAINLY POSSIBLE. COLDER AIR
SPILLING INTO THE AREA TONIGHT WILL PUSH TEMPERATURES INTO THE
TEENS ACROSS THE HIGHLANDS...TO NEAR 30 IN THE PIEDMONT.
TEMPERATURES WILL MOVE VERY LITTLE ON TUESDAY...REMAINING IN THE
20S MOUNTAINS...AND 30S TO NO MORE THAN 40 EAST OF THE BLUE RIDGE.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 400 PM EST MONDAY...

TUESDAY NIGHT OUR REGION WILL CONTINUE TO BE WITHIN A NORTHWEST FLOW
REGIME ON THE BACKSIDE OF THE DEEPENING LOW PRESSURE SYSTEM OFF THE
NEW ENGLAND COAST. NORTHWEST FLOW...WITH A ORIGIN ACROSS LAKE
ERIE...WILL BRING MOISTURE UPSLOPE ACROSS THE SOUTHEAST WEST
VIRGINIA MOUNTAINS...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH
CAROLINA. ANTICIPATE LIGHT ACCUMULATIONS OF SNOW ALONG THE PREFERRED
WESTERN SLOPES. AMOUNTS WILL BE GREATEST IN WESTERN GREENBRIER
COUNTY WHERE LESS THAN INCH OF NEW MEASURABLE SNOW IS EXPECTED.
ELSEWHERE...THE SNOW WILL LIKELY BE IN THE FORM OF FLURRIES...OR
ACCUMULATING SNOW THAT PRODUCES A DUSTING ON SURFACES. WINDS WILL
GUST ACROSS THE MOUNTAINS IN THE 20 TO 30 MPH RANGE WITH LESSER
MAGNITUDES ACROSS THE PIEDMONT.

BY WEDNESDAY...HIGH PRESSURE WILL BE BUILDING INTO THE AREA AND LOW
LEVEL WINDS WILL WEAKEN AND VEER MORE NORTHERLY...THUS TURNING OFF
THE UPSLOPE SNOW MACHINE. ANTICIPATE A TREND TOWARD LITTLE OR NO
CLOUD COVER AND WEAKENING WINDS.

WEDNESDAY NIGHT INTO THURSDAY...THE CENTER OF THE SURFACE HIGH WILL
SHIFT EAST OF THE REGION WHILE OUR NEXT CLIPPER SYSTEM HEADS
SOUTHEAST THROUGH THE GREAT LAKES REGION. LOOK FOR WINDS TO BACK
SOUTHWEST AND INCREASE THROUGH THIS TIME PERIOD...ALONG WITH AN
ONSET OF WARM AIR ADVECTION. CLOUD COVER WILL START TO INCREASE FROM
WEST TO EAST WEDNESDAY NIGHT SO THAT BY DAYBREAK THURSDAY MOSTLY
CLOUDY TO CLOUDY CONDITIONS ARE EXPECTED ACROSS THE ENTIRE FORECAST
REGION. OUR NEXT CHANCE OF PRECIPITATION WILL ARRIVE IN THE WEST BY
MIDDAY THURSDAY AS THE CLIPPER SYSTEM HEADS INTO THE OHIO VALLEY.
THE ONSET OF PRECIPITATION LOOKS AT THIS TIME TO BE A RAIN/SNOW MIX
IN THE WEST. AS PRECIPITATION SPREADS EAST DURING THE...MILDER AIR
WILL ALLOW FOR THE VAST MAJORITY OF THE PRECIPITATION TO TRANSITION
TO PLAIN RAIN.

TEMPERATURES WILL MODERATE DURING THIS TIME PERIOD...ESPECIALLY
ACROSS WESTERN PARTS OF THE AREA ONCE WARM AIR ADVECTION STARTS
WEDNESDAY NIGHT INTO THURSDAY.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 400 PM EST MONDAY...

BELOW NORMAL TEMPERATURES TRENDING TO MUCH BELOW THROUGH THE
EXTENDED...ALONG WITH STRONG NORTHWEST WINDS THURSDAY NIGHT/FRIDAY
AND AGAIN SUNDAY NIGHT/MONDAY.

UPPER LEVELS WILL BE EVOLVING TO MORE OF A DOMINANT NORTHERN STREAM.
THE LATEST INDICATIONS POINT TO A COLDER MORE AMPLIFIED EASTERN TROF
DEVELOPING AS PER THE ECMWF...AND SPLIT FLOW OUT WEST WITH A RIDGE
FOR THE PACIFIC NW AND A CUTOFF LOW REGENERATING OVER THE BAJA
PENINSULA.

THURSDAY NIGHT STARTS OUT WITH A COLD FRONT PUSHING THROUGH FOLLOWED
BY UPSLOPE SNOW SHOWERS FOR THE WESTERN SLOPES OF THE APPALACHIANS
WITH BLUSTERY NORTHWEST WINDS. THE SNOW SHOWERS AND BLUSTERY
CONDITIONS WILL CONTINUE INTO FRIDAY. HIGH PRESSURE THEN BUILDS IN
WITH FAIR WEATHER AND COLD TEMPERATURES FOR THE START OF THE
WEEKEND.

IT NOW APPEARS THAT A COLD FRONT WILL BE APPROACHING FROM THE WEST
ON SUNDAY...BRINGING A GOOD CHANCE OF PRECIPITATION TO THE REGION.
THE FRONT WILL PUSH THROUGH SUNDAY NIGHT...ALLOWING VERY STRONG
NORTHWEST WINDS TO USHER IN A SHOT OF ARCTIC AIR AND COLD
TEMPERATURES FOR THE START OF NEXT WEEK. THE ECMWF HAS BEEN
CONSISTENT WITH THIS MESSAGE AND NAEFS ANOMALIES NOW SUPPORT THE GFS
TREND TOWARD THIS SOLUTION SO CONFIDENCE IS GROWING IN THIS COLD
OUTBREAK.


&&

.AVIATION /22Z MONDAY THROUGH SATURDAY/...
AS OF 100 PM EST MONDAY...

LOW PRESSURE OVER THE MID ATLANTIC WILL MOVE NORTHEAST DEVELOPING
INTO A MAJOR COASTAL STORM FOR NEW ENGLAND. AS THE STORM
STRENGTHENS THIS EVENING AND OVERNIGHT...MUCH COLDER AIR WILL
ADVECT INTO THE CENTRAL APPALACHIANS SUPPORTING SNOW SHOWERS AND
BLUSTERY NORTHWEST WINDS.

FOR A TIME THIS AFTERNOON AND EVENING...IFR CIGS WILL DEVELOP
EAST OF THE MOUNTAINS PER A SHALLOW MOIST NORTHEAST WIND. ONCE THE
NORTHWEST WIND DEVELOPS THIS EVENING...THIS CLOUD LAYER SHOULD
LIFT. HOWEVER...CLOUD BASES OVER THE MOUNTAINS WILL REMAIN LOW
WITH PERIODS OF SNOW SHOWERS AND FLURRIES.

HIGH CONFIDENCE FOR AREAS OF MVFR AND OCNL IFR CONDITIONS THROUGH
THIS EVENING WITH HIGH CONFIDENCE FOR MVFR CONDITIONS LINGERING
OVER THE MOUNTAINS THROUGH TUESDAY.

EXTENDED DISCUSSION...
NORTHWEST FLOW CONTINUES ON TUESDAY. MVFR CONDITIONS LIKELY
ACROSS KBLF/KLWB AND PERHAPS EVEN KBCB DUE TO SCATTERED UPSLOPE
SNOW SHOWERS. EASTERN TAF LOCATIONS SHOULD BECOME VFR ON TUESDAY.
HIGH PRESSURE ON WEDNESDAY WILL PROVIDE A QUIET DAY WITH VFR
CONDITIONS ACROSS ALL TAF LOCATIONS. ANOTHER CLIPPER SYSTEM
ARRIVES ON THURSDAY...BRINGING A CHANCE OF SUB-VFR CEILINGS AND
VSBYS.

&&

.EQUIPMENT...
HINTON ALL HAZARDS RADIO...162.425MHZ WAS OFF THE AIR THIS
MORNING. TECHNICIANS INDICATE THERE IS QUITE A BIT OF TREE DAMAGE
FROM ICE IN THE AREA AND THE RADIO WILL CONTINUE EXPERIENCE
INTERMITTENT OUTAGES DUE TO POWER INTERUPTIONS IN THE AREA.

THE ROANOKE TRANSMITTER...POOR MOUNTAIN 162.475 MHZ...IS ALSO
EXPERIENCING PROBLEMS WITH INTERMITTENT OUTAGES. SIMILAR
CONDITIONS EXIST ON POOR MOUNTAIN WITH THE POWER BEING INTERRUPTED
BY TREE DAMAGE FROM ICE.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     VAZ019-020.
     WINTER WEATHER ADVISORY UNTIL NOON EST TUESDAY FOR VAZ015.
NC...WINTER WEATHER ADVISORY UNTIL NOON EST TUESDAY FOR NCZ001-018.
WV...WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
     WVZ507-508.

&&

$$
SYNOPSIS...PM
NEAR TERM...PM
SHORT TERM...DS
LONG TERM...MBS
AVIATION...PM
EQUIPMENT...PM


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