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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 102325
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
625 PM EST TUE DEC 10 2013

.SYNOPSIS...
SNOW SHOWERS AND PERHAPS A HEAVIER SNOW SQUALL ARE EXPECTED
WEDNESDAY AHEAD OF A STRONG ARCTIC COLD FRONT. HIGHS ON THURSDAY
WILL ONLY BE IN THE TEENS AREA WIDE AND NOT MUCH WARMER FRIDAY.
PERHAPS A FEW SNOW SHOWERS EACH DAY. A STORM SYSTEM WILL PROBABLY
AFFECT THE REGION LATE SATURDAY INTO SUNDY, BRINGING THE
POSSIBILITY OF A WIDESPREAD SNOW.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
-- Changed Discussion --
AS OF 625 PM EST TUESDAY...FORECAST IN GOOD SHAPE AS WE HEAD INTO
THE EVENING HOURS. DID OPT TO NOSE POPS UP INTO THE CHC CATEGORY
FOR MUCH OF THE HIGHER TERRAIN OF CENTRAL/SRN/EAST CENTRAL VT THIS
EVENING/TONIGHT AS WEB CAMS AND A FEW OBS SHOWING LAKE ONTARIO
SHSN BAND MAKING IT EAST INTO THESE AREAS. ACCUMULATIONS
NEGLIGIBLE...LESS THAN AN INCH...BUT SCT FLAKES WILL BE FLYING
HERE AND THERE IN THESE AREAS THUS THE SLIGHT UPWARD ADJUSTMENT.
ONLY OTHER CHANGE WAS TO LOWER SKY COVER SLIGHTLY OVER THE NEXT 2
TO 4 HOURS BASED ON SOME PARTIAL CLEARING NOTED IN IR IMAGERY/SFC
OBS HERE AND THERE. HAVE A GREAT EVENING.

PRIOR DISCUSSION...
MID LAYER CLOUDS FROM THE STORM THAT PASSED BY TO OUR SOUTH ARE
NEARLY GONE, LEAVING BEHIND JUST SOME LOW LEVEL INSTABILITY
CUMULUS (WHICH ARE PRODUCING A FEW FLURRIES). UPSTREAM WE HAVE AN
UPPER LEVEL TROUGH HEADING THIS WAY, SO EXPECT SOME ADDITIONAL
CLOUDS TO STREAM ACROSS OVERNIGHT. AHEAD OF THAT TROUGH THE FLOW
TURNS FROM WESTERLY TO MORE SOUTHWEST, AND AFTER MIDNIGHT WE
SHOULD SEE THE LAKE ONTARIO SNOW BAND PIVOT A BIT AND START TO
SPREAD AT LEAST A LITTLE LIGHT SNOW INTO THE CENTRAL ADIRONDACKS.
PERHAPS SOME MOISTURE MAKING IT ALL THE WAY ACROSS AND DROPPING
SOME LIGHT SNOW ACROSS THE SOUTH- CENTRAL SECTIONS OF THE GREEN
MOUTAINS. IN GENERAL, FAIRLY UNEVENTFUL. STUCK WITH A BLEND OF
MODEL TEMPERATURES, SO LOTS OF TEENS WITH SINGLE NUMBERS IN THE
HIGHER TERRAIN.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 350 PM EST TUESDAY...AS WE START WEDNESDAY, WE SHOULD
CONTINUE TO SEE THE LAKE EFFECT BAND SHIFT A BIT MORE, SPREADING
SOME SNOW SHOWERS INOT SOUTHEAST ST LAWRENCE COUNTY AND SOUTHERN
FRANKLIN COUNTY IN NORTHERN NY. COULD BE A FEW INCHES OF
ACCUMULATIONS IN ISOLATED SPOTS. LATER SHIFTS WILL NEED TO CHECK
OUT THE NEED FOR ANY LAKE EFFECT SNOW ADVISORIES.

OTHERWISE THE MAIN WEATHER MAKER WILL BE AN APPROACHING COLD FRONT
THAT IS ASSOCIATED WITH THE UPPER TROUGH. ELEMENTS STILL LOOK TO
BE IN PLACE FOR A 6 HOUR WINDOW WHERE THAT FRONT COULD GENERATE
LOCALIZED SNOW SQUALLS. HAVE A LITTLE BIT OF INSTABILITY AND WITH
THE SOUTHWEST WINDS AHEAD OF THE FRONT, THAT WILL PROVIDE BOTH
SOME FRONTAL CONVERGENCE AND BE ABLE TO TAP MOISTURE FROM THE LAKE
ONTARIO SNOW BAND. MAIN PERIOD IS ABOUT 20Z WHEN THE FRONT AND IT`S
ASSOCIATED SNOW SHOWERS AND SQUALLS WILL BE UP ALONG THE NY/CANADA
BORDER TO ABOUT 03Z WHEN IT REACHES A LINE FROM NORTHEAST VT TO
THE SOUTHERN CHAMPLAIN VALLEY.

THE SNOW SQUALLS COULD DUMP 1/2" OR SO IN LESS THAN 30 MINUTES,
AND LEAD TO SOME SLICK ROAD CONDITIONS. A BRISK SOUTHWEST WIND,
GUSTING 25 TO 30 MPH WILL ALSO BLOW THAT SNOW AROUND, CAUSING EVEN
MORE REDUCED VISIBILITIES.

THAT FRONT WILL ALSO USHER IN SOME COLD AIR. 850MB TEMPERATURES
AHEAD OF THE FRONT WILL BE AROUND -18C (ALREADY CHILLY TO BEGIN
WITH) AND FALL TO -20 TO -24C AFTER. HOW COLD IT GETS WEDNESDAY
NIGHT WILL DEPEND ON WHETHER WE CLEAR OUT. STILL MAINTAIN SOME
CLOUDINESS, BUT STILL COLD ENOUGH TO GO SUB-ZERO IN THE COLDER
AREAS AND JUST SINGLE DIGITS IN THE "WARMER" VALLEYS.

THURSDAY WILL BE COLD. TEENS WILL BE IT FOR THE HIGHS. DECENT
AMOUNT OF LOW LEVEL MOISTURE AROUND, SO DON`T BE SURPRISED FOR A
FEW FLURRIES.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 350 PM EST TUESDAY...PRETTY MUCH RELIED ON THE SUPERBLEND
(BLEND OF ALL AVAILABLE GUIDANCE) AS IT IS USUALLY THE BEST WAY TO
GO, AND AGAIN IN THIS CASE IT SEEMS LIKE QUITE A REASONABLE FORECAST.

DAILY SPECIFICS:
FRIDAY...STILL BELOW NORMAL TEMPERATURES WITH 850MB HEIGHTS ABOUT
-13 TO -16C. HIGH TEMPERATURES WILL STRUGGLE TO THE LOWER 20S FOR
THE LOW ELEVATIONS. TEENS ELSEWHERE. AT LEAST THAT IS WARMER THAN
IT WILL BE THURSDAY! WEAK TROUGH EMBEDDED WITHIN A BROAD WESTERLY
FLOW SHOULD PICK UP MOISTURE FROM THE GREAT LAKES AND GIVE US
QUITE A BIT OF CLOUDS AND A FEW FLURRIES OR LIGHT SNOW SHOWERS.
HAVE PAINTED IN QUITE A BIT OF 25-35% POPS.

SATURDAY AND SUNDAY...THIS CONTINUES TO BE THE PRIMARY POINT OF
INTEREST FOR THE LONG RANGE AS THERE REMAINS A STORM THREAT. DECENT
AMOUNT OF CONSISTENCY (THOUGH FAR FROM IDENTICAL SOLUTIONS)
BETWEEN 12Z EURO AND 12Z GFS. SO CONFIDENCE IS MODERATE WE WILL
SEE SOME EFFECTS. TOO FAR OUT TO PINPOINT ANY DETAILS. MODELS BOTH
SHOW A PRIMARY LOW WITH THE UPPER TROUGH OVER THE GREAT LAKES,
WHILE ENERGY GETS TRANSFERRED TO A SECONDARY COASTAL LOW BEGINNING
LATE SATURDAY. GFS IS A BIT STRONGER WITH THE PRIMARY LOW THAN THE
EURO. EITHER WAY, THIS TYPE OF SCENARIO IS TYPICALLY NOT ONE FOR
ANY HUGE DUMPS OF SNOW. RATHER WE USUALLY END UP WITH DECENT SNOWS
ON THE LEADING EDGE WARM AIR ADVECTION, AND THEN GET DRY SLOTTED
AND LOSE THE MOISTURE AND LIFT, LEADING TO ONLY LIGHT PRECIPIATION
FOR THE 2ND HALF OF A STORM. INITIAL GUT FEELING IS FOR A
WIDESPREAD ADVISORY LEVEL SNOW EVENT, BUT AGAIN TOO FAR TO REALLY
PINTPOINT ANYTHING. BEST ADVICE -- CONTINUE TO FOLLOW LATER
FORECASTS! WITH THE INCREASING CONFIDENCE IN SOME STORM, HAVE
INCREASED POPS INTO THE LIKELY CATEGORY FOR SATURDAY NIGHT AND
INTO SUNDAY. PRECIPITATION WILL COME TO AN END SUNDAY NIGHT.

MONDAY...ADDITIONAL SHOT OF CHILLY AIR COMES IN THE WAKE OF THE
DEPARTING STORM. 850MB TEMPERATURES DROP TO -16 TO -19C (BRRR).
ANOTHER DAY WITH HIGHS IN THE TEENS AREA WIDE. SOME RESIDUAL
MOISTURE, MAINLY HIGHER TERRAIN OF THE NORTHEAST KINGDOM, SO
PERHAPS A FEW FLURRIES THERE, OTHERWISE DRY.

TUESDAY...HIGH PRESSURE STARTS THE DAY. WILL PROBABLY BE A COLD
START GIVEN RELATIVELY NEW SNOW COVER, WITH SUB-ZERO READINGS
NEARLY EVERYWHERE OUTSIDE OF THE CHAMPLAIN VALLEY. BRRR. OTHERWISE
FAST FLOW ALOFT WILL START TO BRING THE HARBINGERS OF ANOTHER
SYSTEM (MUCH WEAKER), SO HAVE SOME INCREASING CLOUDS AND LOW
CHANCES FOR SNOW SHOWERS.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
THROUGH 18Z WEDNESDAY...GENERALLY VFR ACROSS THE REGION, THOUGH A
FEW LIGHT SNOW SHOWERS/FLURRIES ARE FOUND HERE AND THERE AND THEY
ARE PRODUCING A MOMENTARY DROP TO MVFR. HAVE ADDED A FEW "VCSH" IN
SOME TAF SITES BASED ON CURRENT RADAR TRENDS.

PERSISTENT WESTERLY FLOW FOR THE REST OF TODAY AND OVERNIGHT
SHOULD KEEP THE LOTS OF CLOUDS ACROSS THE AREA, BUT ONLY MINIMAL
CHANCES OF ANY FLURRIES/LIGHT SNOW SHOWERS.

COME WEDNESDAY, FLOW VEERS SOUTHWEST AHEAD OF A FRONT. EXPECT SNOW
SHOWERS TO SPREAD ACROSS NORTHERN NY BY 18Z...ELSEWHERE AFTER THAT POINT.


OUTLOOK 18Z WEDNESDAY THROUGH SUNDAY...

18Z WEDNESDAY THROUGH 12Z THURSDAY...MVFR AND IFR AT TIMES AS
ARCTIC FRONT BRINGS SCATTERED SNOW SHOWERS.
12Z THURSDAY THROUGH 18Z SATURDAY...GENERALLY VFR WITH HIGH
PRESSURE.
18Z SATURDAY ONWARD...INCREASING CHANCES OF MVFR/IFR IN SNOW.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.

&&

$$
SYNOPSIS...NASH
NEAR TERM...JMG/NASH
SHORT TERM...NASH
LONG TERM...NASH
AVIATION...NASH