-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 301045
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
545 AM EST FRI JAN 30 2015

.SYNOPSIS...
-- Changed Discussion --
LOW PRESSURE OVER NEW ENGLAND WILL MOVE EAST AND OFF THE NEW
ENGLAND COAST TODAY...FOLLOWED BY HIGH PRESSURE FOR SATURDAY.
ANOTHER AREA OF LOW PRESSURE WILL MOVE OUT OF THE SOUTHWESTERN
UNITED STATES ON SATURDAY...CROSSING THE CENTRAL PART OF THE
NATION SUNDAY...AND REACHING THE EAST COAST BY MONDAY MORNING.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
AS OF 500 AM EST FRIDAY...

SURFACE CYCLONE RESIDES TO OUR NORTH OVER NEW ENGLAND WITH A
SURFACE COLD FRONT TRAILING SOUTH THROUGH THE MID ATLANTIC REGION.
THIS FRONT CROSSED OUR FORECAST AREA DURING THE OVERNIGHT
RESULTING IN WINDS SHIFTING TO THE NORTHWEST. TEMPERATURES HAVE
FALLEN INTO THE 30S BEHIND THE FRONT...BUT ARE EXPECTED TO TAKE A
MORE SUBSTANTIAL TUMBLE LATER THIS MORNING AS A SECONDARY SURGE OF
COLD AIR ARRIVES FROM THE NORTHWEST. THIS COLDER AIR WAS
ASSOCIATED WITH A STRONG UPPER LEVEL DISTURBANCE WHICH IS EXPECTED
TO CROSS THE MOUNTAINS BETWEEN 9AM AND NOON. THIS DISTURBANCE WILL
LIKELY RESULT IN AN ENHANCEMENT OF THE SNOW SHOWER ACTIVITY OVER
THE MOUNTAINS IN ADDITION TO FALLING TEMPERATURES AND A FURTHER
INCREASE IN WIND SPEED.

THE FORECAST FOR TODAY IS ESSENTIALLY UNCHANGED. A WINTER WEATHER
ADVISORY REMAINS IN EFFECT FOR THE HIGHLANDS OF WV...WITH AN
ADDITIONAL 2 TO 3 INCHES OF SNOW EXPECTED FOR PLACES LIKE
QUINWOOD/CRAWLEY WV (THEY HAD AN INCH OR TWO ON THE GROUND AS OF
4AM). 1 TO 2 INCHES OF SNOW IS STILL POSSIBLE FARTHER SOUTH
THROUGH BLUEFIELD AND INTO THE HIGH COUNTRY OF NC...WITH A DUSTING
IN THE NEW RIVER VALLEY...AND SCATTERED FLURRIES AS FAR EAST AS
THE BLUE RIDGE. A WIND ADVISORY WILL REMAIN IN EFFECT FOR ALL
COUNTIES NEAR THE BLUE RIDGE AND ACROSS THE VA/NC HIGHLANDS/HIGH
COUNTRY. WINDS WILL CONTINUE TO INCREASE THIS MORNING AND PEAK
THIS AFTERNOON WITH GUSTS IN THE 40-55 MPH RANGE...THE STRONGEST
GUSTS NEAR THE RIDGE CRESTS. STRONG MOMENTUM MIX DOWN ALOFT WILL
ALSO RESULT IN SOME HEALTHY WIND GUSTS ACROSS THE PIEDMONT OF
VA/NC WITH POTENTIAL FOR 35 MPH GUSTS TO BE OBSERVED FOR
DANVILLE.

COLD HIGH PRESSURE WILL BUILD SOUTHEAST ACROSS THE OHIO VALLEY AND
INTO THE MID ATLANTIC REGION TONIGHT. TEMPERATURES WHICH WILL
STRUGGLE TO RISE TODAY DUE TO THE STRONG COLD AIR ADVECTION...WILL
TAKE A MORE SERIOUS NOSE DIVE TONIGHT...READINGS DIPPING INTO THE
SINGLE DIGITS AND TEENS WEST OF THE BLUE RIDGE...AND INTO THE
LOWER 20S (POSSIBLY THE UPPER TEENS) FOR AREAS EAST OF THE BLUE
RIDGE. WINDS TONIGHT WILL RESULT IN WIND CHILL VALUES DIPPING
INTO THE SINGLE DIGITS FOR MOST AREAS...AND BELOW ZERO IN THE
HIGHER ELEVATIONS.
-- End Changed Discussion --

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
-- Changed Discussion --
AS OF 400 AM EST FRIDAY...

HIGH PRESSURE OVER EASTERN KENTUCKY SATURDAY MORNING WILL BUILD
SOUTHEAST INTO SATURDAY NIGHT. IF WINDS STAY UP SATURDAY
MORNING...WIND CHILLS NEAR ZERO ACROSS THE HIGHER ELEVATIONS TO
AROUND 10F ABOVE IN THE LOWER ELEVATIONS. IN THE EAST...UPPER TEEN
WIND CHILLS ARE LIKELY. A NICE SATURDAY EXPECTED WITH PLENTY OF
SUNSHINE. HIGH TEMPERATURES WILL WARM INTO THE MID 20S IN THE
NORTHWEST MOUNTAINS TO THE MID 40S IN THE PIEDMONT.

AS LOW PRESSURE MOVES NORTHWARD INTO THE TENNESSEE VALLEY...CLOUD
COVER WILL INCREASE SATURDAY NIGHT INTO SUNDAY MORNING. LOW
TEMPERATURES SATURDAY NIGHT WILL BE WARMER THAN FRIDAY NIGHT WITH
READINGS FROM AROUND 20 DEGREES IN THE MOUNTAINS TO AROUND 30
DEGREES ALONG THE SOUTHEAST BLUE RIDGE MOUNTAINS.

AN UPPER LEVEL NORTHERN STREAM TROUGH WILL SWING OUT OF THE ROCKIES
AND TRAVEL EAST SUNDAY INTO SUNDAY NIGHT. THE STRENGTH OF THIS
TROUGH MAY HOLD THE KEY TO SUNDAY COMPLICATED WEATHER FORECAST WITH
TEMPERATURES AND PLACEMENT OF SNOW ACCUMULATIONS. THIS MORNING 00Z
GFS...ECMWF AND CANADIAN GUIDANCE HAS SHIFTS THE PLACEMENT AND TRACK
OF THE LOW FURTHER NORTH FOR SUNDAY.

THE P-TYPE QUESTION HAS BEEN A CHALLENGE WITH SUNDAY FORECAST.
TEMPERATURES AND THICKNESSES START COLD ACROSS THE MOUNTAINS FOR
PRECIPITATION TO FALL AS SNOW. IF DRY AIR IS LEFT-OVER FROM
DEPARTING HIGH PRESSURE...PRECIPITATION FALLING COULD SEND WET BULB
TEMPERATURES DOWN BELOW FREEZING...KEEPING MOUNTAIN PRECIPITATION AS
SNOW AND A COLD RAIN IN THE EAST. IF THE SURFACE LOW BECOMES
STRONGER...MORE WARM AIR WILL SURGE INTO THE AREA CHANGING SNOW OVER
TO RAIN THROUGH THE DAY SUNDAY...THEN COLD AIR ENTERS LATE SUNDAY
NIGHT TO CHANGE RAIN BACK TO SNOW.  MOS TEMPERATURES REMAIN QUITE
CONSISTENT FOR HIGHS SUNDAY WITH READINGS IN THE LOWER 30S IN THE
NORTHWEST MOUNTAINS TO THE MID 40S IN THE PIEDMONT.

THE LOW PRESSURE CENTER LIFTS NORTHEAST AND BY SUNDAY NIGHT IS
LOCATED NEAR ANNAPOLIS. THE TRAILING COLD FRONT WILL SWEEP EAST
ACROSS OUR REGION SUNDAY NIGHT. THIS IS WHEN THE UPSLOPE SNOW
SHOWERS AND SNOW FLURRIES WILL REALLY KICK IN. SOME SNOW
ACCUMULATIONS ARE POSSIBLE IN THE WEST WITH THE HIGHEST TOTALS IN
THE WESTERN GREENBRIER COUNTY. SOME ADVISORY LEVEL SNOW
ACCUMULATIONS COULD BE POSSIBLE IN THE NORTHWESTERN MOUNTAINS BY
MONDAY MORNING. WILL MENTION POTENTIAL FOR SNOW IN THE HWO. LOW
TEMPERATURES SUNDAY NIGHT WILL RANGE FROM THE TEENS IN THE NORTHWEST
TO THE UPPER 30S IN THE SOUTHEAST.
-- End Changed Discussion --
&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 330 PM EST THURSDAY...

TEMPERATURES BELOW NORMAL THROUGH THE EXTENDED...TRENDING TO MUCH
BELOW NORMAL TOWARD THE END OF NEXT WEEK.

MODELS KEEP THINGS PROGRESSIVE AND ARE CONSISTENT IN PHASING THE
UPPER LEVEL SPLIT FLOW PATTERN INTO A LONG WAVE WESTERN
TROF/EASTERN RIDGE PATTERN. THIS WILL OPEN THE DOOR FOR A SHOT OF
ARCTIC AIR AS WE GET TOWARD THE END OF THE PERIOD.

WE START THE PERIOD WITH A COASTAL LOW OFF THE MIDDLE ATLANTIC
COAST PULLING AWAY FROM THE REGION...LEAVING US WITH COLDER AIR
MOVING IN AND RESIDUAL NORTHWEST UPSLOPE FLOW SNOW SHOWERS WEST OF
THE BLUE RIDGE. THE SNOW SHOWERS COME TO AN END MONDAY NIGHT AS
HIGH PRESSURE BUILDS IN FROM THE OHIO VALLEY AND BRINGS US QUIET
AND COLD WEATHER FOR TUESDAY AND TUESDAY NIGHT.

THE NEXT CHANCE FOR PRECIPITATION COMES ON WEDNESDAY AS DEEPENING
LOW PRESSURE SYSTEM IS DRIVEN BY A VIGOROUS SHOT WAVE THROUGH THE
GREAT LAKES REGION AND INTO CANADA. THIS WILL SWING A COLD FRONT
THROUGH THE REGION...OPENS THE DOOR TO ARCTIC HIGH PRESSURE
BUILDING IN FROM THE MIDWEST. MODEL RUN TO RUN VARIABILITY IN THE
EXTENDED HAS BEEN QUITE HIGH RECENTLY AND WHILE EVOLUTION OF THE
OVERALL SYNOPTIC PATTERN SEEMS SOLID...DO NOT HAVE A LOT OF
CONFIDENCE IN SPECIFICS FROM ANY OF THE INDIVIDUAL SOLUTIONS. THE
EURO IS QUITE AGGRESSIVE IN DIGGING THE EASTERN TROF AND DEVELOPS
A COASTAL LOW MOVING OUT OF THE GULF WITH A CHANCE OF WINTRY
PRECIPITATION FOR OUR NORTH AND WEST AREAS...WHILE THE GFS/NAEFS
IS LESS AMPLIFIED AND DOES NOT ADVERTISE A COASTAL LOW AND KEEPS
US MOSTLY DRY. WILL HAVE TO WAIT AND SEE HOW THIS ALL PLAYS OUT IN
LATER MODEL RUNS BUT FOR NOW WILL SHADE THE FORECAST TOWARD THE
DRIER GFS/NAEFS.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
AS OF 1215 AM EST FRIDAY...

THE STRONG ADVERTISED ALBERTA CLIPPER COLD FRONT MOVING RAPIDLY
THROUGH THE WESTERN PART OF THE CWA AT THIS HOUR...NEAR BCB AND
ALREADY THROUGH LWB/BLF. VERY QUICKLY CIGS DROP INTO THE MVFR/IFR
RANGE BEHIND THE FRONT WITH MIXED PCPN...WHICH SHOULD RAPIDLY
CHANGE TO SNOW WITH STRONG LOW-LEVEL COLD ADVECTION. ALONG AND
EAST OF THE BLUE RIDGE...WINDS LIGHT AND VARIABLE WITH MOSTLY LOW
END VFR CIGS AT THIS HOUR. MODELS NOW DEPICTING A WAVE THAT WILL
RIDE ALONG THE FRONT...WHICH COULD SLIGHTLY DELAY ITS PROGRESS
INTO THE PIEDMONT AND FURTHERMORE BRING A WAVE OF -SHRA TO BCB/ROA
BEFORE THE COLD FRONT ARRIVES OR SHORTLY THEREAFTER. HAVE THUS INTRODUCED
THESE CHANGES TO THE TAFS...SLIGHTLY DELAYING THE ARRIVAL OF THE
FRONT INTO ROA/LYH/DAN AND ALSO INTRODUCING -SHRA TO BCB/ROA THAT
WERE NOT IN THE 00Z TAFS. UPSLOPE -SHSN SHOULD CONTINUE TO BE
ENHANCED WEST OF THE BLUE RIDGE OVERNIGHT INTO EARLY FRI...WITH
OCCASIONAL MVFR TO BRIEFLY IFR VSBYS AND IFR-LIFR CIGS. CONDITIONS
SHOULD BEGIN TO IMPROVE AFT 14Z WITH JUST FLURRIES OR OCCASIONAL
-SHSN THROUGH THE EARLY AFTERNOON WEST OF THE BLUE RIDGE. EXPECT
MVFR CIGS TO HOLD MUCH OF THE DAY WEST OF THE BLUE RIDGE...BUT
CLOUDS SHOULD SCATTER OUT TO THE EAST. EXPECT VFR CIGS AROUND 22Z
BLF/LWB/BCB...BECOMING MOSTLY SKC OR JUST SCT ALL SITES AFT 22Z.

MAIN CONCERN THROUGH THE TAF VALID PERIOD WILL BE STRONG...GUSTY
NORTHWEST WINDS. WITH A 50KT NORTHWESTERLY LLJ OVER THE REGION
LATE TONIGHT/EARLY FRI AS A TIGHT PRESSURE GRADIENT DEVELOPS
BETWEEN THE ADVANCING CANADIAN HIGH AND THE DEPARTING SFC LOW
NORTHEAST U.S...30-40KT WIND GUSTS WILL BE POSSIBLE LATE TONIGHT
AND THROUGH EARLY AFTERNOON FRI. SUSTAINED WINDS SHOULD BE MAINLY
IN THE 15-25KT RANGE. WINDS REMAIN GUSTY EVEN INTO FRI
EVENING...BUT SHOULD DROP BELOW 25KTS FAIRLY QUICKLY AFT 02Z.
WINDS OVERALL WILL AVERAGE 10KTS LESS ACROSS THE PIEDMONT.

MEDIUM CONFIDENCE IN CIGS AND VSBYS THROUGH 14Z...THEN MEDIUM TO
HIGH CONFIDENCE.
MEDIUM TO HIGH CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID
PERIOD.

EXTENDED DISCUSSION...

WINDS WILL DIMINISH FRIDAY NIGHT AS HIGH PRESSURE MOVES INTO THE
REGION FROM THE WEST. ANY REMAINING LOW CLOUDS LINGERING ACROSS
EASTERN WV SHOULD DISSIPATE...WITH VFR CIGS EXPECTED FRI NIGHT AND
SAT. THE NEXT LOW PRESSURE SYSTEM HEADING OUT OF THE SW STATES
WILL BRING A RETURN OF CLOUDS AND PRECIPITATION ON SUNDAY WITH
WIDESPREAD MVFR TO IFR CIGS/VSBYS LIKELY WITHIN THIS TIME FRAME.
THE NORTHERN SECTIONS OF THE CWA WILL LIKELY SEE MOSTLY WINTER
PRECIPITATION WITH THIS EVENT...WHILE THE SOUTHERN AREAS SHOULD
SEE MOSTLY RAIN. IN BETWEEN...LOCATIONS SUCH AS
BCB/ROA/LYH...COULD SEE A MIX OF RAIN AND SNOW. MOUNTAIN SNOW
SHOWERS WITH MVFR CIGS/VSBYS WILL CONTINUE INTO MON...WITH STRONG
AND GUSTY WINDS ALL AREAS BY MONDAY AFTERNOON. IMPROVING
CONDITIONS ARE EXPECTED BY TUESDAY.

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...WIND ADVISORY UNTIL 9 PM EST THIS EVENING FOR VAZ009>014-
     016>020-022>024-032>035.
     WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VAZ015.
NC...WIND ADVISORY UNTIL 9 PM EST THIS EVENING FOR NCZ002.
     WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NCZ001-018.
WV...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR WVZ508.

&&

$$
SYNOPSIS...PM
NEAR TERM...PM
SHORT TERM...KK
LONG TERM...MBS
AVIATION...DS/RAB