Area Forecast Discussion
Issued by NWS Blacksburg, VA

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000
FXUS61 KRNK 220553
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
153 AM EDT WED OCT 22 2014

.SYNOPSIS...
LOW PRESSURE CENTERED OVER PENNSYLVANIA WILL DRIFT SOUTHEAST AND
OFF THE DELMARVA COAST BY WEDNESDAY. THIS CYCLONE WILL STRENGTHEN
INTO A NOR-EASTER THAT WILL PELT NEW ENGLAND WITH HEAVY RAINFALL.
BACKLASH FROM THIS SYSTEM WILL BE FELT ACROSS OUR REGION THROUGH
THURSDAY IN THE FORM OF CONSIDERABLY CLOUDY COOL WEATHER ALONG
WITH GUSTY NORTHWEST WINDS. A MODERATING TREND WILL OCCUR OVER
THE WEEKEND AS THE STORM SYSTEM MOVES AWAY FROM THE AREA...REPLACED
BY HIGH PRESSURE THAT WILL BRING WARMING CONDITIONS FOR THE
WEEKEND...AND ABOVE NORMAL TEMPERATURES FOR THE LAST WEEK OF
OCTOBER.

&&

.NEAR TERM /THROUGH TODAY/...
AS OF 1243 AM EDT WEDNESDAY...
UPPER LEVEL LOW CONTINUES TO DROP SOUTHEAST OVERNIGHT INTO
WEDNESDAY. SHORTWAVES PIVOTING AROUND THE LOW CENTER TRIGGER
SCATTERED SHOWERS. INCREASED POPS ACROSS THE NORTHEAST AND EAST TO
MATCH UP BETTER WITH LATEST RADAR TRENDS. ADJUSTED TEMPERATURES
WITH SFC OBS AND SHAPED TRENDS TOWARDS LAV GUIDANCE. MORE LATER
THIS MORNING...


AS OF 945 PM EDT TUESDAY...

ADJUSTED TEMPS DOWNWARD ACROSS THE MOUNTAINS IN THE NEAR TERM AS
THEY ARE COOLING OFF MUCH QUICKER THAN ANTICIPATED. LIGHT RAIN
CONTINUES ACROSS SE WV...AND MORE SCATTERED ACROSS THE NRV AND
ALLEGHANY HIGHLANDS. AS ANTICIPATED PRECIP AMOUNTS HAVE BEEN
LIGHT...WITH JUST A FEW HUNDREDTHS ACROSS SE WV. ALL OTHER
PREVIOUS FORECAST DETAILS REMAIN INTACT.

AS OF 300 PM EDT TUESDAY...

LOW PRESSURE WAS CENTERED OVER PENNSYLVANIA WITH A COLD FRONT
TRAILING SOUTHWEST THROUGH THE CENTRAL APPALACHIANS. THE FRONT
WILL CROSS THE FORECAST AREA THIS EVENING PRODUCING A FEW
SHOWERS...BUT THE GREATER IMPACT WILL BE FOR AREAS NORTHEAST OF
OUR REGION WHERE SHOWERS/STORMS WILL INCREASE IN COVERAGE PER THE
DEVELOPING/STRENGTHENING AREA OF LOW PRESSURE OVER PENNSYLVANIA.
AS THE LOW PASSES OFF THE COAST TONIGHT...THE CYCLONE IS PROGGED
TO DEEPEN RAPIDLY...YIELDING TO SURFACE PRESSURE FALLS OF ABOUT
10MB IN 12 HOURS ONCE IT PASSES OFF THE DELMARVA COAST. THIS RAPID
STRENGTHENING WILL RESULT IN A NOR-EASTER THAT WILL PELT NEW
ENGLAND WITH HEAVY RAIN AND WIND. FOR OUR REGION...WE WILL BE ON
THE SOUTHWEST SIDE OF THE STORM...THE DRY SIDE...SO THE BIGGEST
BY-PRODUCT WILL BE CLOUD COVER AND WIND. SOME THREAT FOR SHOWERS
WILL EXIST OVER THE VA/WV HIGHLANDS...AND ACROSS OUR NORTHEASTERN
COUNTIES VCNTY OF BUCKINGHAM WHERE WRAP AROUND MOISTURE FROM THE
STORM MAY RESULT IN A PERIOD OF PRECIP TONIGHT AND WEDNESDAY.
ASIDE FROM THIS THREAT...THE GREATER INFLUENCE THAT MOST FOLKS
WITHIN OUR CWA SHOULD NOTICE WILL BE THE WIND. 85H WINDS ARE
PROGGED AROUND 40 KTS FROM THE NORTHWEST WEDNESDAY. THIS WILL TRANSLATE
INTO BREEZY CONDITIONS AT THE SURFACE WITH WIND GUSTS OF 20 TO 30
MPH...AND 30 TO 35 MPH IN THE HIGHER ELEVATIONS. TEMPERATURES
TONIGHT WILL BE COOL...BUT SHOULD REMAIN ABOVE FREEZING DUE TO THE
CLOUD COVER AND MIXING FROM THE WIND. TEMPERATURES WEDNESDAY WILL
STRUGGLE TO REACH 50 IN THE MOUNTAINS...AND 60 IN THE PIEDMONT...
CLOUD COVER AND LOWERING THICKNESSES FROM THE DEVELOPING CYCLONE
PUTTING A DAMPER ON ANY CONTRIBUTION FROM SOLAR INSOLATION.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
AS OF 300 PM EDT TUESDAY...

WE WILL BE WATCHING AN OCCLUDED LOW/NOR-EASTER DRIFT OFF THE MID
ATLANTIC COAST WEDNESDAY NIGHT AND THURSDAY. SHORT WAVES PIVOTING
AROUND THIS LOW WILL PERIODICALLY TRACK OVER THE FORECAST AREA.
MOISTURE WILL BE LIMITED BUT COULD SEE A PASSING SHOWER OR TWO
ACROSS THE GREENBRIER VALLEY AND ALLEGHANY HIGHLANDS THROUGH THE DAY
THURSDAY. MOST NOTABLE WILL BE A PRESSURE GRADIENT OVER THE REGION
BETWEEN THE NOR-EASTER AND APPROACHING HIGH PRESSURE FROM THE WEST.
BREEZY/GUSTY CONDITIONS LIKELY ALONG RIDGE TOPS AND POSSIBLY FOR
LOWER ELEVATIONS IF SKIES BECOME MOSTLY CLEAR. MOST CLEAR SKIES
POSSIBLE FOR THE SOUTHWEST CORNER OF RNK CWA (BLUEFIELD TO GRAYSON
COUNTY). DOWNSLOPE FLOW SHOULD ALSO KEEP THE EAST MOSTLY CLEAR
ESPECIALLY ACROSS SOUTHSIDE...BUT THE WINDS WILL NOT BE AS STRONG
EAST AS IT WILL BE OVER THE MOUNTAINS. CLOUDS BEGIN TO CLEAR ACROSS
THE ENTIRE CWA THURSDAY NIGHT...WHILE THE PRESSURE GRADIENT RELAXES.
ANY WINDS OVERNIGHT THURSDAY WILL REMAIN ALOFT AND ABOVE THE
INVERSION.

MODELS ARE BRINGING ANOTHER UPPER LEVEL TROUGH ACROSS THE OHIO
VALLEY AND OVER THE MID ATLANTIC FRIDAY. THIS TROUGH WILL HAVE LESS
MOISTURE TO WORK WITH THAN THE NOR-EASTER...THEREFORE RAINFALL
CHANCES ARE EVEN LOWER BUT NOT ZERO ALONG WESTERN SLOPES FRIDAY
AFTERNOON. THIS TROUGH QUICKLY MOVES EAST FRIDAY NIGHT WITH HEIGHTS
BUILDING THERE AFTER.

COOL NORTHWEST FLOW ON THE BACK SIDE OF THE MID ATLANTIC LOW/NOR-
EASTER WILL KEEP AFTERNOON TEMPERATURES COOLER THAN NORMAL THURSDAY
AND FRIDAY. OVERNIGHT LOWS MAY DIP INTO THE 30S ACROSS THE MOUNTAINS
EACH NIGHT WHILE MIXING WILL DETER FROST FROM FORMING.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 300 PM EDT TUESDAY...

A LARGE AREA OF HIGH PRESSURE WILL COVER MOST OF THE CONUS...FROM
THE ROCKIES MOUNTAINS TO THE EAST COAST...STARTING SATURDAY. THE
UPPER RIDGE AXIS WILL BE ALIGNED OVER THE EAST COAST ON MONDAY.
BASICALLY...HEIGHTS WILL INCREASE EACH DAY WHICH TRANSLATES INTO
WARMER THAN NORMAL TEMPERATURES FOR THE AREA THROUGH MONDAY. HEIGHTS
BEGIN TO LOWER ON TUESDAY AS A COLD FRONT ENTERS THE MISSISSIPPI
VALLEY.

SURFACE HIGH PRESSURE WILL ACCOMPANY RIDGING ALOFT THIS WEEKEND.
THIS SURFACE HIGH WILL ENCOMPASS THE EASTERN HALF OF THE
US...ESSENTIALLY BLOCKING ANY RETURN FLOW FROM THE GULF. WITH NO
LIFT AND/OR MOISTURE...HIGH CONFIDENCE TO RUN WITH ZERO POPS INTO
MONDAY NIGHT.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
AS OF 153 AM EDT WEDNESDAY...

CLOSED LOW WILL DRIFT OFF THE DELMARVA COAST TODAY...AND WILL BE
THE PRIMARY FOCUS FOR WEATHER THROUGHOUT THE REGION THE NEXT
SEVERAL DAYS. THIS FEATURE WILL RESULT IN THE DEVELOPMENT OF A
NOR-EASTER THAT WILL PELT THE NEW ENGLAND COAST WITH HEAVY RAIN A
WIND...AND WILL MOST LIKELY IMPACT AIR TRAFFIC FOR MANY OF THE NEW
ENGLAND TERMINALS FOR THE REMAINDER OF THIS WORK WEEK.

FOR OUR LOCAL REGION...BKN-OVC CLOUD BASES WILL BE COMMON THROUGH
TODAY...MAINLY VFR EAST OF THE BLUE RIDGE...AND MVFR ACROSS THE
MOUNTAINS. SCATTERED SHOWERS ARE POSSIBLE OVER THE VA/NC
HIGHLANDS...AND ACROSS VIRGINIA NORTH OF A KROA/KLYH
LINE...HIGHWAY 460. ISOLATED SHOWER OR SPRINKLE POSSIBLE FROM THE
VA/NC STATE LINE AND POINTS SOUTH.

WITH THE DEVELOPING CYCLONE TO OUR NORTHEAST...BACKLASH WILL BE
FELT THROUGHOUT OUR REGION IN THE FORM OF GUSTY NORTHWEST WINDS.
3000-5000FT AGL WINDS OF 40 KTS ARE PROGGED FOR WEDNESDAY. THIS
WILL RESULT IN GUSTY SURFACE WINDS AT ALL TERMINALS. 20-30KT
SURFACE GUSTS WILL BE COMMON. THE UPPER LOW WILL SLIDE EASTWARD
TONIGHT INTO THURSDAY. ISOLATED TO SCATTERED SHOWERS WILL CONTINUE
IN THE WEST TONIGHT...WHILE THE EAST WILL DRY OUT.

MEDIUM CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE
PERIOD.


EXTENDED AVIATION DISCUSSION...

THE UPPER LEVEL LOW WILL SLOWLY MEANDER ABOUT THE MID-ATLANTIC
REGION THROUGH THURSDAY...THEN BEGIN TO SHIFT TOWARD THE
NORTHEAST AND AWAY FROM THE AREA BY FRIDAY. IMPACTS...ESPECIALLY FROM
WIND...WILL CONTINUE IN ADDITION TO WIDELY SCATTERED -SHRA ACROSS
THE VA/WV HIGHLANDS EARLY THURSDAY. MVFR CLOUDS WILL THUS BE
COMMON ACROSS THE MOUNTAINS DURING THIS TIME PERIOD...BUT FROM ROA
TO LYH TO DAN CONDITIONS ARE LIKELY TO REMAIN VFR THROUGH THIS
PERIOD.

VFR CONDITIONS ARE ANTICIPATED FRIDAY-SUNDAY. WINDS MAY CONTINUE
TO BE A CONCERN FRIDAY AND SATURDAY...BUT ARE EXPECTED TO DIMINISH
FOR SUNDAY INTO MONDAY AS HIGH PRESSURE BUILDS OVER THE REGION
FROM THE WEST.

&&

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

&&

$$
SYNOPSIS...PM
NEAR TERM...CF/KK/PM
SHORT TERM...RCS
LONG TERM...RCS
AVIATION...DS/KK/PM



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