651 
FXUS61 KBTV 081813
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
113 PM EST FRI FEB 8 2013

.SYNOPSIS...
A LOW PRESSURE AREA OVER THE OHIO VALLEY AND ANOTHER LOW ALONG
THE MID ATLANTIC COAST WILL COMBINE TO FORM A POWERFUL WINTER
STORM OFF THE MID ATLANTIC COAST TODAY. THIS STORM WILL CONTINUE
TO DEEPEN TODAY AND TONIGHT AND WILL BE SOUTH OF CAPE COD LATE
TONIGHT AND HEADING TOWARD NOVA SCOTIA ON SATURDAY. A RIDGE OF
HIGH PRESSURE WILL BUILD INTO THE REGION SATURDAY NIGHT AND WILL
BE OVER THE NORTH COUNTRY ON SUNDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1208 PM EST FRIDAY...ISSUED UPDATE TO ZONES TO EXPAND HEAVY
SNOW WORDING ACROSS MUCH OF THE CWA WEST OF THE GREEN MTNS.
INVERTED TROUGH OVER THE NORTH COUNTRY PROVIDING ENHANCED SNOWFALL
OVER THE PAST COUPLE HRS AND SHOULD CONTINUE INTO THE AFTNOON.
SNOW TOTALS IN THIS AREA ON TRACK TO MEET WARNING CRITERIA...BUT
MAY HAVE TO BUMP UP WITH NEXT ISSUANCE IF CURRENT INTENSITY
CONTINUES. ALSO ADJUSTED TEMP TRENDS TO PARE DOWN BY A FEW
DEGREES...ESPECIALLY OVER NORTHERN ZONES. REST OF FORECAST IN GD
SHAPE. 

PREVIOUS DISCUSSION...ISSUED EARLY UPDATE TO UPGRADE THE CVLY
AND NORTHERN ST LAW VALLEY TO WINTER STORM WARNING FROM ADVISORY.
REPORTS OF SNOWFALL ALREADY RECEIVED IN THESE AREAS ALREADY COMES
CLOSE TO TOPPING CURRENT ADVISORY NUMBERS. WITH MORE ACCUM
EXPECTED OVER THE NEXT 24 HRS...WE WILL HIT WARNING NUMBERS IN THE
AFOREMENTIONED AREAS. REST OF AREA IN GD SHAPE FOR WARN/ADV ATTM.
SOME MINOR ADJUSTMENTS TO TEMPS OTHERWISE FORECAST IN GD SHAPE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
AS OF 540 AM EST FRIDAY...MOISTURE FROM THE LOW ALONG THE MID
ATLANTIC COAST WILL MOVE INTO THE REGION TONIGHT...WITH THE
HEAVIEST QPF TONIGHT ACROSS SOUTH CENTRAL VERMONT. SOUTH CENTRAL
VERMONT COULD SEE 10 TO 20 INCHES OF SNOW BY SATURDAY MORNING.
ELSEWHERE...EXPECTING 8 TO 14 INCHES WHERE THE WINTER STORM
WARNING IS IN PLACE AND AROUND 6 TO 9 INCHES IN THE AREA WHERE THE
WINTER WEATHER ADVISORY IS IN EFFECT. THE LOW WILL BE EAST OF CAPE
COD BY DAYBREAK ON SATURDAY. EXPECTING LIGHT SNOW SATURDAY MORNING
TO COME TO AN END BY MIDDAY. A RIDGE OF HIGH PRESSURE WILL BUILD
INTO THE REGION LATE SATURDAY AFTERNOON AND WILL BE CENTERED OVER
THE REGION BY SUNDAY. GIVEN FRESH SNOW COVER AND CLEAR
SKIES...EXPECTING TEMPERATURES TO FALL BELOW ZERO BY DAYBREAK ON
SUNDAY. GFS MOS GUIDANCE LOOKS A BIT TOO COLD WITH MIN
TEMPERATURES SATURDAY NIGHT... ESPECIALLY GIVEN THAT WINDS WILL BE
UP THE FIRST PART OF THE NIGHT...BUT EXPECTING WINDS TO DIMINISH
AFTER MIDNIGHT SATURDAY NIGHT...AS HIGH PRESSURE BUILDS INTO THE
REGION. HAVE USED THE GRIDDED MOS GUIDANCE FOR MIN TEMPERATURES
SATURDAY NIGHT.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 301 PM EST THURSDAY...NO SIGNIFICANT CHANGES TO DAYS 4 THRU
7...AS LONG WAVE PATTERN CONTS TO SUPPORT ACTIVE WEATHER WITH
POTENTIAL FOR TWO SYSTEMS. FIRST SYSTEM WL IMPACT CWA LATE MONDAY
INTO TUESDAY...WITH RIBBON OF MOISTURE/LIFT MOVING FROM SW TO NE
ACRS OUR FA. MODELS IN GOOD AGREEMENT WITH TRACK OF SFC LOW PRES
TO OUR WEST ACRS THE CENTRAL GREAT LAKES AND TIMING OF ASSOCIATED
QPF. BASED ON QUICK MOVEMENT AND DEVELOPMENT OF DRY SLOT ON
BACKSIDE...EXPECT QPF AMOUNTS BTWN 0.15 AND 0.40"...WITH AN
ADVISORY TYPE LIKELY FOR PARTS OF OUR CWA...MAINLY THE MTNS/NEK.
THERMAL PROFILES SUPPORT A BURST OF SNOW AS INITIAL BAND OF WAA
LIFTS ACRS THE CPV/SLV...BUT 1000 TO 500MB THICKNESS VALUES AT OR
SLIGHTLY ABOVE 540 INDICATE THE POTENTIAL FOR MIXED PRECIP. GIVEN
GOOD RUN TO RUN CONSISTENCY BTWN GFS/ECMWF/GEM...I HAVE INCREASED
POPS TO LIKELY FOR LATE MONDAY/EARLY TUES. OTHERWISE...SOME
UNCERTAINTY CONTS FOR LATE WEEK SYSTEM...AS SEVERAL SOLUTIONS SHOW
MUCH LESS TROF AMPLIFICATION AND LOW PRES SHEAR OUT WAY TOO OUR
SOUTH. WL CONT TO MENTION LOW CHC POPS AT THIS TIME...AND WL CONT
TO WATCH FOR ANY POTENTIAL PHASING WITH NORTHERN STREAM ENERGY
DROPPING ACRS THE NORTHERN PLAINS. TEMPS WL BE AT OR ABOVE NORMAL
FOR DAYS 4 THRU 7 WITH HIGHS MAINLY IN THE U20S MTNS TO M/U30S
VALLEYS...AND LOWS MAINLY IN THE UPPER TEENS TO UPPER 20S...MAYBE
A FEW L30S TUES/WEDS MORNINGS IN THE CPV.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 18Z SATURDAY...SIGNIFICANT IMPACT TO AVIATION AND GROUND-
BASED OPERATIONS OWING TO MODERATE TO OCCASIONALLY HEAVY SNOW AT
THE TAF LOCATIONS THROUGH THE REMAINDER OF TODAY UNTIL THE PRE-
DAWN HOURS SATURDAY. FRONTAL BOUNDARY ACROSS THE AREA BRINGING
STEADY IFR CONDITIONS WITH SNOW AND VSBY GENERALLY BELOW 1 MILE. 
SNOW IS STEADIEST ACROSS NORTHERN AREAS...WITH LIGHTER SNOW AT
RUT. AS COASTAL LOW DEEPENS OFF DELMARVA AND MOVES SE OF CAPE COD
TONIGHT...ANTICIPATE KRUT BECOMING IFR IN SNOW AFTER 21Z. LOW
PULLS EAST OF CAPE COD TOMORROW MORNING WITH WINDS BECOMING N-NW
AT 10-15 KTS WITH GUSTS UP TO 25 KTS. MAY SEE A FEW GUSTS TO 30
KTS TOWARD 18Z SATURDAY. SNOW GENERALLY ENDS BY 12Z SATURDAY WITH
VSBY BECOMING P6SM AND CEILINGS RISING TO 2000-3500 FT BY 15Z SAT.

OUTLOOK 18Z SATURDAY THROUGH WEDNESDAY...STORM SYSTEM CLEARS OUT
OF THE REGION WITH HIGH PRESSURE BUILDING IN FROM THE GREAT LAKES
REGION ACROSS THE NORTH COUNTRY SAT NIGHT AND SUNDAY. THIS HIGH
PRESSURE SYSTEM WILL BRING DIMINISHING WINDS SATURDAY NIGHT AND
GENERALLY VFR CONDITIONS. WINDS SHIFT INTO THE SOUTH BY MONDAY
MORNING AS RIDGE AXIS SHIFTS EAST OF NEW ENGLAND. NEXT FRONTAL
SYSTEM BRINGS A PERIOD OF MIXED WINTRY PCPN AND MVFR/OCCASIONAL
IFR CONDITIONS MONDAY AFTN INTO MONDAY NIGHT. GENERALLY VFR
TUESDAY AND WEDNESDAY...HOWEVER LIGHT SNOW SHOWERS MAY LINGER AT
MPV/SLK WITH NW LOW-LEVEL FLOW IN PLACE. 

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...WINTER STORM WARNING UNTIL 1 PM EST SATURDAY FOR VTZ001-002-
     005-006-008>012-016>019.
     WINTER WEATHER ADVISORY UNTIL 1 PM EST SATURDAY FOR VTZ003-004-
     007.
NY...WINTER STORM WARNING UNTIL 1 PM EST SATURDAY FOR NYZ026>031-
     034-035-087.

&&

$$

SYNOPSIS...WGH
NEAR TERM...JN
SHORT TERM...WGH
LONG TERM...TABER
AVIATION...BANACOS