-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRNK 050639
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
139 AM EST THU DEC 5 2013

.SYNOPSIS...
-- Changed Discussion --
A WEAK WARM FRONT WILL PUSH NORTH OF THE AREA TONIGHT. A STRONG
BUT SLOW MOVING COLD FRONT PUSHES EAST INTO THE APPALACHIANS
THURSDAY NIGHT BEFORE CRAWLING ACROSS VIRGINIA LATER FRIDAY.
STRONG COLD HIGH PRESSURE TO THE NORTH WILL RIDGE DOWN ALONG THE
MOUNTAINS SATURDAY BEFORE INTERACTING WITH PRECIPITATION RETURNING
NORTH BY SUNDAY.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
-- Changed Discussion --
AS OF 124 AM EST THURSDAY...

MIN T FOR LEWISBURG AND MARION WERE SEVERAL DEGREES ABOVE CURRENT
TEMPS AT THOSE LOCATIONS. WITH MORE NUMEROUS CLOUDS ON
ARRIVAL...THOSE COLD SPOTS SHOULD WARM A FEW DEGREES INTO DAWN.
ELSEWHERE...TEMPS SHOULD BE RATHER STEADY FOR THE REST OF THE
NIGHT. WILL BE WATCHING EXTREME SW VA FOR A DENSE FOG ADVISORY
LATER TONIGHT.
-- End Changed Discussion --

&&

.SHORT TERM /8 AM THIS MORNING THROUGH SATURDAY NIGHT/...
-- Changed Discussion --
AS OF 300 PM EST WEDNESDAY...

THURSDAY WILL SEE LITTLE REAL CHANGE IN THE AIR MASS PROPERTIES
WITH STILL VERY MILD SOUTHERLY FLOW ACROSS THE CWA. MORE
WIDESPREAD CLOUDINESS WILL LIMIT DAYTIME HEATING...WHICH MAY BE
THE ONLY THING HOLDING BACK SOME RECORD HIGHS TOMORROW.

SLOW MOVING COLD FRONT AGAIN THE MAIN FOCUS AS WEAK LOW PRESSURE
PASSES TO THE NORTH THURSDAY EVENING ALLOWING THE LOW LEVEL
BOUNDARY TO SAG SE ACROSS THE FAR NORTHERN SECTIONS BY EARLY
FRIDAY. HOWEVER THE DEEPER SWATH OF MOISTURE/LIFT AND ASSOCIATED
PRECIP WILL STILL BE ALONG THE 85H PORTION OF THE BOUNDARY AND
MAINLY JUST WEST OF THE REGION. THEREFORE HAVE SLOWED POPS UP SOME
THU NIGHT WITH A SWATH OF LIKELYS EXTREME WEST...CHANCE BLUE
RIDGE...AND ONLY ISOLATED COVERAGE SE. MAIN ASPECT WILL BE WITH
VERY MILD OVERNIGHT LOWS GIVEN CLOUDS...MIXING AHEAD OF THE FRONT
UNDER THE STRONG JET ALOFT AND RATHER MOIST DEWPOINTS. THIS COULD
RESULT IN RECORD HIGH MIN TEMPS IN THE 50S TO LOWER 60S PER
CLIMATE SECTION BELOW.

MODELS AGREE ON THE FRONT BASICALLY REMAINING STUCK ACROSS THE
FAR WEST/NORTH FRIDAY AS ANOTHER WAVE RIDES UP THE BOUNDARY
KEEPING STRONG WARM ADVECTION EAST AND OOZING COLD ADVECTION
NORTH-NW. MAIN AXIS OF SHOWERS LOOKS TO STILL BE FROM THE WESTERN
MOUNTAINS AND POINTS WEST DURING THE DAY WITH PERHAPS A FEW BANDS
ACROSS THE SOUTH/EAST WHERE GUIDANCE INDICATES SOME SHALLOW
INSTABILITY. CAN`T TOTALLY RULE OUT A RUMBLE OF THUNDER ALONG THE
LEADING EDGE OF THE HEAVIER SHOWERS WEST AS WELL BUT WILL LEAVE
OUT ALL AREAS FOR NOW. SHOWERS COULD ALSO FOLD SOUTH ACROSS THE NE
SECTIONS WHERE WINDS MAY SHIFT TO THE NE AROUND LYH BEFORE
REACHING BCB/ROA FRIDAY EVENING. DESPITE CLOUDS...VERY WARM HIGHS
IN STORE FRIDAY WITH SOME LOW/MID 70S POSSIBLE SE AND 60S BACK TO
THE BLUE RIDGE.

WAVE WILL BOOT E/SE FRI NIGHT ALLOWING THE BOUNDARY TO FINALLY
ACCELERATE A BIT MORE ESPCLY SAT WHEN THE STRONGER DRIER ADVECTION
FROM THE NW WILL BE ONGOING. LATEST EC SUGGESTS A SWATH OF
WEAKENING SHOWERS WILL HEAD SE WITH THE FRONT FRIDAY NIGHT...THEN
PERHAPS ENHANCE SOME OVER THE SE LATE WHERE THE WAVE MAY SLOW THE
FRONT DOWN A LITTLE. THUS WILL HAVE CAT/LIKELY POPS
OVERNIGHT...THEN MAINLY CHANCE POPS BLUE RIDGE SOUTH AND EAST
SATURDAY WHEN MANY SOLUTIONS SHOW THINGS DRYING EVEN MORE FROM NW
TO SE. COLDER AIR MAY CATCH THE PRECIP JUST BEFORE IT ENDS FAR NW
EARLY SATURDAY BUT LITTLE MORE THAN SPOTTY WINTRY MIX AT THIS
POINT. TEMPS BEGIN TO CRASH BY SAT WITH HIGHS ONLY 35-40 WEST AND
MOSTLY 40S BLUE RIDGE EAST AS THE WEDGE STARTS TO DIG IN.

ANY DRYING WILL BE SHORT AS YET ANOTHER WAVE HEADS UP WEST OF
THE MOUNTAINS AND THE STRONG ARCTIC HIGH TO THE NORTH ENTRENCHES
DOWN EAST OF THE BLUE RIDGE BY SUNDAY MORNING. SOME GUIDANCE HAS
THINGS DRIER WITH MOISTURE SLOWER TO RETURN NORTH SAT NIGHT WHILE
THE GFS REMAINS THE FASTEST WITH A LARGE AXIS OF MODERATE PRECIP
LIFTING ACROSS THE AREA LATE SATURDAY NIGHT AHEAD OF THE WAVE.
THIS ALONG WITH TIMING OF THE BEST LOW LEVEL DRY/COLD ADVECTION
MAKES TIMING OF POTENTIAL ICING IFFY SAT NIGHT WITH CONSENSUS
INDICATING THIS SCENARIO DEVELOPING FROM NE TO SW MOSTLY AFTER
MIDNIGHT. SOUNDINGS SHOW A TYPICAL BELOW FREEZING LAYER AROUND
2-3K FT WHICH WILL MAKE FOR THE BEST ICING ALONG THE BLUE RIDGE IN
VIRGINIA AND ACROSS THE FAR NE CLOSER TO THE PARENT HIGH. APPEARS
MOST OF THESE AREAS EXCLUDING NW NC INTO SOUTHSIDE VA ALONG WITH
THE FAR SW...WILL SEE AT LEAST A PERIOD OF DECENT ELEVATED TYPE
ICING BY SUNDAY MORNING AS TEMPS FALL INTO THE UPPER 20S
NORTH/EASTERN SLOPES TO THE LOW/MID 30S ELSW. OTRW WILL FOLLOW
MORE OF A BLEND OF POPS WITH MOST OF THE SW HALF SEEING LIKELY
POPS LATE WITH HIGH CHANCES ELSW FOR NOW.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
AS OF 400 PM EST WEDNESDAY...

WILL START THE DAY ON SUNDAY WITH A WEATHER PATTERN IDEAL FOR
FREEZING RAIN ACROSS MUCH OF OUR AREA NORTH OF HIGHWAY 460...AND
POSSIBLY SLEET NORTH OF INTERSTATE 81. ARCTIC HIGH PRESSURE WILL
BE WEDGED AGAINST THE EASTERN FACE OF THE APPALACHIANS...RESULTING
IN A COLD NORTHEASTERLY WIND ACROSS THE VA PIEDMONT...SHIFTING
SOUTHEASTERLY FROM THE BLUE RIDGE WESTWARD ACROSS THE MOUNTAINS.
MEANWHILE...AN UPPER LEVEL TROUGH WILL APPROACH FROM THE PLAINS...
WITH STRONG SOUTHWESTERLY FLOW OFF THE SURFACE CARRYING WARM GULF
MOISTURE NORTHWARD ALONG THE APPALACHIAN CHAIN.

PRECIPITATION WILL ALREADY BE MOVING ACROSS THE AREA BY SUNRISE
SUNDAY MORNING...WHICH WILL RESULT IN A VERY SLOW WARMUP FROM
EARLY MORNING LOWS...WITH THE WARMUP TAKING PLACE FROM SOUTHWEST
TO NORTHEAST. AS SUCH...AREAS FROM THE GREENBRIER VALLEY INTO THE
PIEDMONT NORTH OF INTERSTATE 81 ARE EXPECTED TO REMAIN BELOW
FREEZING THROUGH MUCH OF THE DAY...AND WILL LIKELY SEE PERIODS OF
FREEZING RAIN THROUGH THE DAY. MODELS ARE STILL JUMPING AROUND A
BIT CONCERNING PRECIPITATION AMOUNTS...SO WILL GIVE IT ONE MORE
DAY BEFORE WE START MENTIONING ICE ACCUMULATIONS.

WARMER AIR WILL CONTINUE TO WORK IN FROM THE SOUTHWEST SUNDAY
NIGHT...WITH THE LAST POCKETS OF FREEZING RAIN ACROSS THE ALLEGHANY
HIGHLANDS AND SHENANDOAH VALLEY ENDING BY SUNRISE MONDAY. WILL
THEN SEE A COLD FRONT PUSH ACROSS THE AREA DURING THE AFTERNOON.
HAVE ADDED A SLIGHT CHANCE OF THUNDERSTORMS FOR PORTIONS OF
SOUTHSIDE VIRGINIA AND THE NORTH CAROLINA PIEDMONT FOR A FEW HOURS
DURING THE AFTERNOON DUE TO STRONG SHEAR ASSOCIATED WITH A 60KT
LOW LEVEL JET PASSING ACROSS THE AREA...WHICH MAY RESULT IN
LOCALLY STRONG SURFACE WINDS IN THE CONVECTION.

THE COLD FRONT MAY STALL ALONG THE COAST MONDAY NIGHT AND TUESDAY
MORNING AS MODELS CONTINUE TO HINT AT A WAVE DEVELOPING ALONG THE
BOUNDARY. BY TUESDAY AFTERNOON...THE FRONT WILL CONTINUE ITS
EASTWARD PUSH...ENDING PRECIPITATION ACROSS OUR AREA AND BRINGING A
RETURN OF DRY HIGH PRESSURE FROM THE WEST. UPPER LEVEL TROUGHING
ACROSS THE NORTHEAST WILL KEEP TEMPERATURES ON THE COOL SIDE DURING
THE MIDDLE OF NEXT WEEK.
-- End Changed Discussion --

&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
AS OF 1135 PM EST WEDNESDAY...

HIGH PRESSURE IS STILL POSITIONED OFF THE COAST. MEANWHILE A
STRONG LOW PRESSURE SYSTEM SITUATED IN THE NORTHERN PLAINS WILL
MAKE ITS WAY TOWARD THE GREAT LAKES ON THURSDAY...ACCOMPANIED BY
A TRAILING COLD FRONT.

STRATUS WILL CONTINUE TO FILL IN EAST OF THE BLUE RIDGE WITH MVFR
TO IFR CEILINGS ON THE EASTERN SLOPES. THE CLOUDS WILL KEEP
VISIBILITIES FROM FALLING MUCH BELOW 4SM. DOWNSLOPE FLOW NEAR
BLF AND LWB...COMBINED WITH THE OVERALL SOUTHWESTERLY FLOW ALOFT
THOSE SITES VFR TO HIGH MVFR INTO THURSDAY. SURFACE WINDS WILL
BECOME SOUTH TO SOUTHWEST ON THURSDAY SO MODERATE TO HIGH
CONFIDENCE THAT TAFS SITES WILL IMPROVE TO VFR BY 18Z/1PM.

EXTENDED AVIATION CONCERNS...A COLD FRONT WILL MAKE SLOW PROGRESS
ACROSS THE AREA FRIDAY...RESULTING IN MVFR AND IFR CONDITIONS IN
ADDITION TO WIDESPREAD RAIN SHOWERS...BEFORE THE FRONT PASSES EAST
FRIDAY NIGHT. MAY SEE A BRIEF IMPROVEMENT TO VFR ON SATURDAY AS
ARCTIC HIGH PRESSURE BUILDS IN...HOWEVER IFR WILL RETURN SATURDAY
NIGHT AS ANOTHER SYSTEM APPROACHES FROM THE WEST...BRINGING
FREEZING RAIN TO THE AREA SUNDAY AND SUNDAY NIGHT FOR MOST
AIRPORTS. A COLD FRONT WILL MOVE THROUGH ON MONDAY...BRINGING A
SLOW IMPROVEMENT TO VFR THROUGH THE DAY AS HIGH PRESSURE RETURNS
FROM THE WEST.

&&

.CLIMATE...
WARM TEMPERATURES THE NEXT COUPLE DAYS WILL APPROACH RECORDS AT THE
CLIMATE SITES. BELOW ARE THE CURRENT RECORDS.

DECEMBER 5 CURRENT RECORD HIGH TEMPERATURES (YEAR)

ROA76(2001)
LYH76(2001)
DAN 75(1982)
BCB70(2001)
BLF71(2001)
LWB68(2001)

DECEMBER 5 CURRENT RECORD HIGH MINIMUM TEMPERATURES (YEAR)

ROA58(1982)
LYH60(1982)
DAN57(1982)
BCB52(1982)
BLF55(1994)
LWB53(1994)

DECEMBER 6 CURRENT RECORD HIGH MINIMUM TEMPERATURES (YEAR)

ROA52(2011)
LYH52(2011)
DAN60(2011)
BCB51(2011)
BLF56(2011)
LWB 52  (1998)

&&

.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.

&&

$$
SYNOPSIS...JH/KM
NEAR TERM...KM
SHORT TERM...JC/JH/PC
LONG TERM...NF
AVIATION...AMS/NF
CLIMATE...CF