Area Forecast Discussion
Issued by NWS Blacksburg, VA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KRNK 220549
AFDRNK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BLACKSBURG VA
149 AM EDT MON SEP 22 2014

.SYNOPSIS...
A COLD FRONT WILL MOVE EAST TONIGHT...AND REACH THE EAST COAST BY
MORNING. MONDAY THROUGH WEDNESDAY...A LARGE HIGH PRESSURE SYSTEM
WILL COVER MUCH OF THE EASTERN UNITED STATES.

&&

.NEAR TERM /THROUGH TODAY/...
AS OF 1045 PM EDT SUNDAY...

AN UPPER TROUGH WILL AMPLIFY ACROSS THE EAST TONIGHT INTO MONDAY.
THE ASSOCIATED COLD FRONT WILL SWEEP EAST ACROSS THE FORECAST AREA
OVERNIGHT. WITH THE PASSAGE OF THE FRONT...WINDS WILL INCREASE FROM
THE NORTHWEST...DEWPOINTS TAKING A NOTICEABLE PLUNGE...READINGS
FALLING INTO THE 40S. THIS AIRMASS CHANGE WILL RESULT IN A
NOTICEABLY COOLER FEELING TO THE AIR STARTING MONDAY.

FRONTAL PASSAGE WILL BRING A GENERAL CLEARING TO AREAS EAST OF THE
MOUNTAINS. UPSLOPE NORTHWESTERLY FLOW WILL RESULT IN LINGERING
CLOUDINESS ALONG THE WESTERN SLOPES.  AN UPPER LEVEL TROUGH WILL
PIVOT ACROSS THE REGION WITH NORTHWEST FLOW AND LOW LEVEL MOISTURE
HOLDING CLOUDS BANKED UP AGAINST WESTERN SLOPES THROUGH MONDAY
MORNING. ONCE THIS TROUGH AXIS TRACKS TO THE MID ATLANTIC COAST
MONDAY AFTERNOON...DRY AIR WILL ERODE MOUNTAIN CLOUDS RETURNING
SUNSHINE. DOWNSLOPE NORTHWEST FLOW ANTICIPATED EAST OF THE BLUE
RIDGE TO KEEP MOSTLY CLEAR SKIES MONDAY. PLAYED HIGH TEMPERATURES
MONDAY CLOSE TO ADJMAV WITH READINGS FROM THE MID 60S IN THE
MOUNTAINS TO THE UPPER 70S IN THE PIEDMONT.

850 MB WINDS OF 25 TO 30 KTS WILL RESULT IN BREEZY CONDITIONS
EARLY MONDAY...ESP ALONG THE RIDGE CRESTS WHERE SURFACE GUSTS OF
25 MPH ARE POSSIBLE.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 240 PM EDT SUNDAY...

LOOKING AT A DRY AND COOL AIRMASS MON NIGHT-WED...WITH SFC HIGH
SHIFTING FROM THE OHIO VALLEY TO OFF THE NORTHEAST COAST. THIS WILL
SET UP A CLASSIC WEDGE OVER OUR AREA...WHICH AT FIRST WILL BE
CLEAR/SUNNY AND DRY/COOL.

WED-WED NIGHT...THE ECMWF HAS BEEN TRENDING TOWARD A
CLOUDIER...WETTER SOLUTION THAN THE OTHER OPERATIONAL MODELS...AND
ATTM LEANING TOWARD A BLEND. THINK POTENTIAL EXISTS FOR ENOUGH
SOUTHEAST FLOW ALOFT AND NE-E FLOW AT THE SFC TO DRAW IN THE SOME
ATLANTIC MOISTURE. FOR NOW WILL LIMIT SLIGHT CHANCE OF RAIN IN THE
EASTERN TWO THIRDS OF THE FORECAST AREA LATE WED NIGHT...WITH
INCREASING CLOUDS.

FOR TEMPS EXPECT THE COOLER MORNING TO BE TUESDAY MORNING...WHERE
SOME VALLEYS IN SE WV/FAR SW VA MAY DROP INTO THE MID TO UPPER 30S
WHILE MOST WILL SEE 40S.

TEMPS REBOUND INTO THE MID TO UPPER 60S FOR HIGHS TUESDAY IN THE
MOUNTAINS...TO LOWER TO MID 70S EAST.

TEMPS MODIFY SOME WED NIGHT WITH 40S MOST PLACES...COOLER IN THE
MOUNTAIN VALLEYS...THEN WARM AGAIN INTO THE MID 60S TO LOWER
70S...WITH WARMEST TEMPS ACROSS THE FAR SW CWA WHILE SE FLOW OUTSIDE
THE WEDGE MAY ENHANCE TEMPS.

WED NIGHT MODIFIES SOME WITH INCREASING CLOUDS WHERE LOWS RANGE FROM
THE UPPER 40S TO LOWER 50S.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 100 PM EDT SUNDAY...

A STRONG SURFACE HIGH OVER THE NE STATES ON THURSDAY WILL SLOWLY
DRIFT WESTWARD TO THE GREAT LAKES BY THE WEEKEND. THIS WILL LEAD TO
A PROLONGED EASTERLY FLOW ACROSS THE REGION. HIGH TEMPERATURES WILL
BE 5-10 DEGREES BELOW NORMAL RANGING FROM THE MID TO UPPER 60S
ACROSS THE MOUNTAINS TO LOWER 70S EAST OF THE BLUE RIDGE.

MODELS ARE STARTING TO AGREE ON A WEAK UPPER LEVEL DISTURBANCE
FORMING ACROSS THE SE STATES LATE IN THE WEEK...HOWEVER THERE IS
STILL MAJOR DIFFERENCES ON PLACEMENT WHICH WILL AFFECT HOW MUCH
MOISTURE CAN GET PULLED UP INTO THE REGION. THE GFS CONTINUES TO BE
MUCH DRIER THAN THE ECMWF. DUE TO THE MODEL DIFFERENCES...ONLY
SLIGHT CHANCE POPS IN FROM THE BLUE RIDGE EASTWARD.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 135 AM EDT MONDAY...

COLD FRONT EXTENDED FROM VERMONT TO EASTERN VIRGINIA TO NORTHERN
LOUISIANA AT 05Z/1AM. SURFACE WIND WERE FROM THE WEST TO
NORTHWEST BEHIND THE FRONT WITH GUSTS UP TO 25 KNOTS AT HIGHER
ELEVATIONS. ENOUGH PRESSURE GRADIENT TO SUPPORT GUSTY WINDS IN THE
MOUNTAINS THROUGH EARLY AFTERNOON.

MVFR CEILINGS ARE EXPECTED TO DEVELOP ALONG THE WESTERN SLOPES
EARLY THIS MORNING. ONLY MEDIUM CONFIDENCE ON THE TIMING OF WHEN
KLWB AND KBLF WILL DROP TO MVFR. BCB WILL BE ON THE EDGE OF VFR
TO MVFR CLOUDS EARLY THIS MORNING.

KLWB...AND ESPECIALLY KBLF WILL SEE THE MVFR CIGS HANG IN MUCH OF
THE DAY WITH UPSLOPE NORTHWEST FLOW. VFR CONDITIONS WILL PREVAIL
TO THE EAST. BCB SHOULD SEE CIGS IMPROVE TO VFR IN THE 15Z/11AM-
17Z/1PM TIME FRAME. AS HIGH PRESSURE BUILDS IN AND THE NORTHWEST
UPSLOPE FLOW WEAKENS...THE CLOUDS WILL ERODE. HIGH CONFIDENCE THAT KLWB
AND KBLF WILL IMPROVE TO VFR BY 00Z.

EAST OF THE BLUE RIDGE...VFR CONDITIONS SHOULD PREVAIL THROUGH
THE TAF VALID PERIOD.

EXTENDED AVIATION DISCUSSION...

HIGH PRESSURE AND DRIER AIR IN THE REGION TONIGHT THROUGH
WEDNESDAY WILL RESULT IN MAINLY VFR CONDITIONS. RIVER VALLEY FOG
WILL STILL BE POSSIBLE AT NIGHT AS WINDS DIMINISH AND COOL AIR
MASS DECOUPLES. A LOW PRESSURE SYSTEM COMING OUT OF THE GULF COAST
MAY BRING IFR CONDITIONS TO THE REGION AS EARLY AS WEDNESDAY
NIGHT.

&&

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

&&

$$
SYNOPSIS...AMS
NEAR TERM...KK/PM
SHORT TERM...WP
LONG TERM...CF
AVIATION...AMS/RAB



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.