-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KBTV 041752
AFDBTV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BURLINGTON VT
1252 PM EST WED DEC 4 2013

.SYNOPSIS...
VARIABLE CLOUDS ALONG WITH SOME PARTIAL SUNSHINE IS EXPECTED TODAY
AS TEMPERATURES REMAIN NEAR SEASONAL EARLY WINTER NORMS. A WARM
FRONT WILL PUSH THROUGH THE REGION LATER TONIGHT INTO THURSDAY
MORNING WITH PERIODS OF LIGHT RAIN AND FREEZING RAIN...THOUGH ANY
ICE ACCUMULATIONS WILL BE VERY LIGHT. TEMPERATURES WILL TREND QUITE
MILD ON THURSDAY...BEFORE COLDER AIR SLOWLY SETTLES BACK INTO THE
REGION BY FRIDAY INTO NEXT WEEKEND. SOME ON AND OFF LIGHT SNOWS OR
MIXED PRECIPITATION WILL BE POSSIBLE ON THE FRONT END OF THE COLDER
AIR DURING FRIDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1229 PM EST WEDNESDAY...MINOR UPDATE TO CAPTURE CRNT
TEMPS/DWPTS AND LATEST SKY COVER. TEMPS ARE SLOW TO WARM ACRS THE
SLV ASSOCIATED WITH NE DRAINAGE FLW...WHILE PARTS OF THE CPV ARE
NEAR 40F. HAVE ADJUSTED TEMPS ACCORDINGLY. OTHERWISE...LIGHT MIXED
PRECIP IMPACTED SLV/WESTERN DACKS THIS MORNING HAS SLOWLY WEAKENED
PER LATEST KTYX RADAR TRENDS. REST OF FCST IN GOOD SHAPE.

THE FOLLOWING CHANGES HAVE BEEN MADE WITH THIS UPDATE...INCREASED
POPS ACRS THE SLV/DACKS TO CHC/LOW LIKELY ACRS EXTREME SOUTHERN ST
LAWRENCE COUNTY AND INCREASED CLOUD GRIDS OVER MOST OF THE
CWA...EXCEPT SOUTHERN/CENTRAL VT ZNS. CRNT RADAR/OBS SHOW A LIGHT
BAND OF SNOW MIXED WITH POCKETS OF FREEZING RAIN ENTERING THE SLV
ATTM WITH OGS REPORTING 1-2SM IN OCCASIONAL LIGHT SNOW/BR.
ALSO...NOTED SOME LIGHT MIXED UPSTREAM ACRS WESTERN/CENTRAL NY
ASSOCIATED WITH THIS INITIAL BAND OF WAA LIFT/MOISTURE. THIS BAND
SHOULD WEAKEN ACRS THE DACKS/SLV BY 18Z TODAY WITH JUST SCATTERED
LIGHT FLURRIES/FREEZING DRIZZLE THIS AFTN. NOT EXPECTING MUCH IN
ACCUMULATION OR QPF. OTHERWISE...VIS SATL PIC SHOWS AREAS OF LOW
CLOUDS ACRS THE VT/NORTHERN NY WITH HIGHER LVL CLOUDS ADVANCING
AHEAD OF NEXT SYSTEM. BOTTOM LINE EXPECT MOSTLY CLOUDY
SKIES...WITH EXCEPTION OF EASTERN/SOUTHERN SECTIONS AND HIGHER
PEAKS OF THE GREENS...WHICH MAYBE ABOVE THE LOWER CLOUD DECK.
TEMPS WL RANGE FROM THE L30S COLDER VALLEYS TO UPPER 30S CPV WITH
MAINLY LIGHT AND VARIABLE WINDS.

PRIOR DISCUSSION...ANOTHER MAINLY QUIET DAY ON TAP FOR THE AREA
AS WEAK RIDGE REMAINS SANDWICHED ATOP OUR AREA BETWEEN BOMBING
MARITIME LOW PRESSURE TO OUR EAST AND AN APPROACHING WARM FRONT TO
OUR WEST. LOW LEVEL 925 MB THERMAL PROGS ESSENTIALLY UNCHANGED
FROM YESTERDAY AND GIVEN AT LEAST SOME PARTIAL SUNSHINE HERE AND
THERE...TEMPERATURES WILL BE RELATIVELY SIMILAR TO YESTERDAY FROM
THE MID 30S TO THE LOWER 40S UNDER LIGHT WINDS. COULD ALSO SEE
SOME VERY LIGHT MIXED PRECIPITATION OR SHSN ACTIVITY ACROSS OUR
NRN NY COUNTIES LATER THIS MORNING INTO EARLY AFTERNOON AS INITIAL
THOUGH DECAYING AREA OF WARM THERMAL ADVECTION RIDES NORTHEAST
THROUGH THE SLV. MODELS REMAIN GENERALLY CONSISTENT IN SHOWING
THIS INITIAL SURGE WEAKENING AS IT ENTERS OUR FORECAST AREA
HOWEVER...SO MOST AREAS SHOULD REMAIN DRY. WILL CLOSELY MONITOR
SHOULD TRENDS PROVE OTHERWISE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
AS OF 346 AM EST WEDNESDAY...WARM FRONT THEN MAKES A MORE
CONCERTED PUSH INTO AND THROUGH OUR AREA TONIGHT INTO THURSDAY
MORNING AS GREAT LAKES LOW LIFTS NORTHEAST TOWARDS THE JAMES BAY
REGION OF CANADA. WHILE LARGE SCALE FORCING FOR PRECIPITATION IS
MODEST AT BEST...AT LEAST SOME ISENTROPIC LIFT THROUGH THE MID
LEVELS TO PRODUCE SCT/AREAS OF LIGHT RAIN OR LIGHT FREEZING RAIN
LATER TONIGHT INTO THE MID MORNING HOURS ON THURSDAY. AGAIN...PCPN
SHOULD REMAIN LIGHT SO I`M NOT LOOKING AT ANY APPRECIABLE ICE
ACCUMULATION...BUT ANY TIME YOU HAVE FREEZING RAIN IT COULD
CERTAINLY LEAD TO SOME LIGHT GLAZING CONCERNS AND LOCALLY SLICK
TRAVEL. BEST THREAT OF THIS OCCURRING WILL BE IN THE SHELTERED
VALLEYS OF THE ADIRONDACK AND GREEN MOUNTAINS. WITH SOUTH TO
SOUTHEASTERLY WINDS SLOWLY INCREASING OVERNIGHT...TEMPERATURES
WILL TAKE ON THE TYPICAL NON-DIURNAL TRENDS...SLOWLY RISING FROM
THE CHAMPLAIN VALLEY WEST AND HOLDING GENERALLY STEADY IN ERN VT
AFTER MIDNIGHT.

ANY LIGHT FREEZING RAIN SHOULD THEN TREND TO JUST PLAIN LIGHT RAIN
OR RAIN SHOWERS DURING THE LATE MORNING/AFTERNOON HOURS ON THURSDAY
AS WARM FRONT CLEARS NORTHEAST AND FORECAST AREA ENTERS A NARROW
BUT SIGNIFICANT WARM SECTOR. INDEED...MODELS CONTINUE TO ADVERTISE
MEAN 925 MPB TEMPS SURGING INTO THE +6 TO +12C RANGE EAST TO WEST
ACROSS THE AREA AND WILL CONTINUE TO OFFER HIGHS GENERALLY ABOVE MOS
GUIDANCE VALUES. TYPICAL IN SUCH SYSTEMS DURING WINTER...DEEPER PBL
MIXING WILL NOT BE REALIZED GIVEN ONLY MARGINAL INSOLATIONAL
HEATING...BUT EVEN SHALLOW MIXING ESTIMATES TO 950 MB SUPPORT PRIOR
IDEA THAT MOST AREAS FROM THE CHAMPLAIN VALLEY WEST SHOULD CLIMB
INTO THE UPPER 40S TO LOWER 50S WITH A FEW SPOT MID 50S POSSIBLE IN
THE SLV. COOL AIR SCOURING PROCESSES TOUGHER TO ACHIEVE ACROSS
EASTERN VERMONT VALLEYS WHERE READINGS SHOULD BE COOLER...LOWER TO
MID 40S. OTHER MINOR ISSUE ON THURSDAY WILL BE INCREASINGLY STRONG
SOUTHERLY FLOW ALOFT BY AFTERNOON/EARLY EVENING AHEAD OF PARENT
OCCLUSION APPROACHING FROM THE WEST. MEAN 925 MB FLOW QUITE DECENT
(40 TO 60 KTS)...ESPECIALLY IN THE CENTRAL TO NORTHERN CHAMPLAIN
VALLEY WHERE CHANNELLED EFFECTS SHOULD ALLOW AT LEAST SOME MODEST
MIXING PROCESSES TO OCCUR. HERE GUSTS FROM 25 TO 35 MPH WITH
ISOLATED HIGHER GUSTS POSSIBLE...LIGHTER ELSEWHERE...ESP ERN VT
WHERE AFOREMENTIONED COOL AIR/LOW LEVEL STABILITY SHOULD INHIBIT
GUSTINESS.

BY THURSDAY NIGHT INTO FRIDAY SFC OCCLUSION SAGS THROUGH THE REGION
AND SETTLES TO OUR IMMEDIATE SOUTH ACROSS THE NRN MID ATLANTIC INTO
SOUTHERN NEW ENGLAND. MODELS REMAIN GENERALLY CONSISTENT IN SHOWING
A MODEST SFC WAVE RIDING ENE ALONG THIS BOUNDARY DURING LATER
THURSDAY NIGHT INTO FRIDAY WITH AT LEAST SOME CONTINUED CHANCE FOR
PCPN...ESP ACROSS OUR CENTRAL AND SOUTHERN COUNTIES. TEMPERATURES
INITIALLY MILD ENOUGH FOR MAINLY LIGHT RAIN AND/OR RAIN SHOWERS
THURSDAY EVENING...BUT AS COLDER AIR SLOWLY FILTERS INTO THE REGION
AND UNDERCUTS LINGERING WARM LAYER ALOFT...A SLOW TRANSITION TO SNOW
SHOWERS OR A PERIOD OF LIGHT MIXED PCPN WILL BE POSSIBLE NW TO SE
OVER TIME. ANY ACCUMULATIONS GENERALLY EXPECTED TO BE LIGHT BUT
COULD SEE AN INCH OR TWO OF SNOW AND/OR MIXED SNOW/PL HERE OR THERE
DURING THE PERIOD...ESP FROM MID SLOPE TO HIGHER ELEVATIONS.
AGAIN...TEMPERATURES BEGIN TO SLOWLY TREND COOLER OVER TIME...ESP BY
FRIDAY AS READINGS REMAIN STEADY OR PERHAPS SLOWLY FALL BY THE
AFTERNOON HOURS.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 338 AM EST WEDNESDAY...A COLD FRONT ACROSS SRN NEW ENGLAND
WILL HAVE A COUPLE WAVES OF LOW PRESSURE RIDE ALONG IT...KEEPING
THREAT OF PRECIP ACROSS THE NORTH COUNTRY FRIDAY NIGHT INTO EARLY
SATURDAY. NW FLOW BEHIND THE FRONT COULD PRODUCE SOME SNOW
SHOWERS ACROSS THE WRN SLOPES OF THE ADKS. BUT AN OVERALL DRYING
TREND WILL TAKE HOLD LATE SATURDAY THROUGH SUNDAY AS RIDGE OF
HIGH PRESSURE BUILDS OVER THE REGION AT THE SFC. AS THE RIDGE
SHIFTS E...SOUTHERLY FLOW WILL RETURN SUNDAY NIGHT INTO
MONDAY...USHERING IN WAA. SFC LOW N OF WRN END OF LAKE ERIE WILL
BOLSTER WAA WITH A LOW LVL JET WHICH WILL FILTER IN WARMER TEMPS
ALOFT...BEFORE WORKING ITS WAS IN AT THE SFC. THIS MEANS PRECIP
ASSOCIATED WITH THE WAA WILL START AS SNOW SUNDAY NIGHT/EARLY
MONDAY MORNING...TRANSITIONING TO A WINTRY MIX MONDAY MIDDAY. THE
SFC LOW WILL TRACK NEWD INTO SWRN QUEBEC BY LATE
MONDAY...CONTINUING TOWARD ERN QUEBEC MONDAY NIGHT. ON THE WEST
SIDE OF THE LOW...COLD TEMPS WILL MOVE IN ON W-NW FLOW...ALLOWING
PRECIP TO CHANGE BACK TO SNOW MONDAY NIGHT INTO EARLY
TUESDAY...WITH DRY SLOT LEADING TO DIMINISHED THREAT OF SHOWERS.
UPPER LVL SHORTWAVE WILL KEEP THREAT OF SNOW SHOWERS THRU THE
REST OF THE PERIOD.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
-- Changed Discussion --
THROUGH 18Z THURSDAY...VFR CONDITIONS EXPECTED THRU 06Z THURSDAY
WITH CEILINGS RANGING FROM BKN035-120 AND WINDS LGT/VAR BECM SSE
5-10KTS...EXCEPT MSS/SLK. AFT 06Z THURSDAY...CEILINGS WILL SLOWLY
LWR TO MAINLY MVFR BY 08Z-12Z FROM W TO E RANGING FROM BKN015-030
AND VFR BKN035 AT BTV. LIGHT -SHSNRA FOR SLK/MSS AND VCSH
ELSEWHERE. WINDSHEAR POTENTIAL AS WELL FROM 07Z-08Z ONWARD WITH
SSW 35-45KTS POSSIBLE...WITH SFC FLOW INCR TO 10-20KTS FROM SSE-
SW.

OUTLOOK 18Z THURSDAY THROUGH MONDAY...

18Z THURSDAY THROUGH 06Z FRIDAY...AREAS OF MVFR/IFR IN LIGHT RAIN
AND SNOW. PSBL LLWS AS STRONG LOW LVL JET OF 40-60KTS MOVES
ACROSS THE NORTH COUNTRY.

06Z FRIDAY THROUGH 12Z SATURDAY...AREAS OF MVFR/IFR IN LIGHT RAIN
AND SNOW.

12Z SATURDAY ONWARD...BECOMING VFR.
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...JMG
NEAR TERM...JMG/TABER
SHORT TERM...JMG/SISSON
LONG TERM...KGM
AVIATION...KGM/JN