933
FXUS61 KBTV 011901
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
201 PM EST Mon Dec 1 2025
.SYNOPSIS...
Our first east coast winter storm of the season will bring
widespread snow to Vermont and northern New York on Tuesday,
with moderate to heavy snow at times mainly in central and
southern Vermont. An Arctic cold front will bring snow showers
and snow squalls to the region as it sweeps eastward during the
day. The coldest weather of the early winter will follow, with
persistent below normal temperatures and snow shower chances
continuing through the weekend.
&&
.NEAR TERM /THROUGH TUESDAY NIGHT/...
As of 201 PM EST Monday...
** Winter Storm Warnings are now in effect from 7 AM Tuesday to
1 AM Wednesday in portions of southern Vermont **
** Winter Weather Advisories are in effect from 7 AM Tuesday to 1 AM
Wednesday in much of northern Vermont and Essex County, New York **
The upcoming snow event is largely on track with widespread 3 to 7
inches of snowfall expected in most of Vermont and southern portions
of the Adirondacks, with amounts dwindling farther north and west.
The latest forecast trended a little snowier farther north/east. The
probability matched-mean snowfall off the latest HREF run, a
skillful reasonable high-end snowfall, now shows totals exceeding 6"
in much of Vermont and exceeding 10" in much of Windsor County,
and portions of Orange and Rutland counties; our current
forecast more closely resembles the ensemble mean, with 6-8"
common in the Winter Storm Warning area and 4-7" where the
advisories are in effect. Much of the event will be a steady,
light to moderate snowfall of roughly 0.5"/hour snow, leading
to snow covered roads and slippery conditions for both the
morning and evening commutes. Snow character will tend to be on
the fluffy side, with perhaps a slight decrease with time,
with average snow ratios largely in the 14-16:1 range. Onset
time of snow will be 5 to 8 AM where headlines are up; while
some light snow is possible in the predawn hours, steady snow
should blossom around 7 AM with the first inch or two of snow
accumulating through the morning.
Between about 10 AM and the remainder of the day, a swath of
heavier snowfall favored in portions of southern Vermont, with
expected mid-level frontogenesis helping to enhance snowfall
rates in both quasi-stationary and laterally-translating bands
that diminish somewhat as they move northward. In these bands,
snowfall rates of 0.5"-1" are expected, and potentially higher
given snow ratios often increase due to strong vertical motion
in the snow growth cloud layer. Residence time will tend to be
longest in a narrow axis which cannot be predicted precisely.
The most intense snow is favored to our south where confidence
in the banded snow is a bit higher. Also, there is a bit more
uncertainty in the ending time, as the back edge of snow
generally will slide eastward during the late afternoon into the
evening, but persist longer in southern and eastern Vermont,
potentially through midnight, which would lead to greater snow
amounts and helps explain an uptick in snow amounts in eastern
Vermont.
As the storm departs, increasing north to northwesterly winds
associated with the backside of the departing, intensifying
storm could cause some drifting of snow, but generally winds
will not be a factor with this event as this period of stronger
winds will tend to be in the early morning hours. High pressure
should build in pretty quickly from the west, leading to
relaxation of winds towards daybreak.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
As of 201 PM EST Monday...Our active weather pattern continues
with only a brief lull on Wednesday. By Wednesday evening, a
well-anticipated cold front will close in on northern New York
with broad southwesterly, cyclonic flow producing a response off
the eastern Great Lakes. As such, snow showers will develop and
move northeastward into St. Lawrence County, probably mainly
focused closer to the immediate valley initially during the
afternoon/early evening before shifting farther east Wednesday
night. Increasing lift ahead of the surface cold front will
begin to cause precipitation to intensify, which could lead to a
band of heavy snow to develop before the showers progress into
the Adirondacks. Towards daybreak, a line of snow showers with
embedded snow squalls will make it into far northwestern
Vermont, stretching southwestward across the Adirondacks. More
details on this Arctic front are included below.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 119 PM EST Monday...Long term impacts include snow showers and
snow squalls on Thursday, followed by bitterly cold
temperatures/wind chills on Thurs night into Friday.
Conditions still look favorable for snow showers and embedded
heavier snow squalls on Thurs associated with arctic boundary. The
locally developed snow squall parameter is still highlighting values
of 2 to 4 acrs the SLV at 12z Thurs and into central/southern VT
around 18z Thurs, and exiting our cwa by 21z Thurs. Latest guidance
shows sharp convergence with arctic boundary with favorable axis of
strong 925mb fgen forcing, and moderate 3 hr pres rise couplet on
backside, supporting snow squall with gusty winds. The only limited
factor may be fropa timing and the associated llvl instability/lapse
rates from minimal sfc heating. NAM/GFS both indicate sharply
falling 925mb temps from -4C to -5C at 12z to -15C to -17C by 21z
Thurs, supporting the potential for a flash freeze. Always difficult
to determine if snow melts or if wind blows snow off the roads, but
potential for a flash freeze is something we will continue to watch
closely. Given the sharpness of the boundary/convergence and
dynamics aloft, would expect any snow squalls to quickly drop sfc
vis <1/4SM, localized wind gusts to 35 mph, and a burst of 1 to 2
inches of snow in 20 mins or less, creating very hazardous travel
conditions on Thurs. Timing looks to be around the morning commute
acrs northern NY and mid morning to mid aftn for most of VT,
including the CPV.
Moderate to strong llvl caa continues on Thursday night with progged
850mb temps falling btwn -18C and -22C by 06z Friday. Difficult to
determine how cold temps get, given gradient, but have values
ranging from -5F SLK to 10F near BTV, due to the warmer lake waters.
Given the extreme instability a few cold air funnels will be
possible over Lake Champlain on Thursday night/Friday morning, along
with some lake effect snow flurries. Limiting factor for additional
snow showers wl be depth of moisture. Wind chills wl be near 0F
valleys to -20F acrs the higher summits late Thurs into Friday.
Mid/upper lvl trof prevails into next weekend with below normal
temps and periods of snow showers possible. Best potential for
accumulating snowfall would be associated with another arctic
boundary and s/w energy late Sat into Sunday. Highest pops and
greatest potential for a light snowfall wl be acrs northern NY and
the mtns of northern/central VT. Temps only in the upper teens to
mid 20s Friday, warm into the mid 20s to lower 30s on Sat, before
cooling back into the upper teens to mid 20s on Sunday/Monday. Lows
generally in the single digits and teens, except lower 20s in the
CPV ahead of boundary on Sat night.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
Through 18Z Tuesday...Any lingering MVFR cigs at our mtn taf
sites will become VFR in the next 1 to 3 hours. Gusty northwest
winds 10 to 15 knots with gusts 20 to 25 knots will become 5 to
10 knots by sunset. Next aviation challenge will be arrival time
of snow on Tuesday morning from southwest to northeast across or
taf sites and associated IFR visibilities. Expecting light snow
with visibilities between 1-2SM (IFR) to develop between 11-13z
on Tuesday with intervals of moderate snow likely with LIFR
(1/2SM) conditions mainly south of a SLK to BTV to 1V4 line by
15z Tuesday. CIGS generally drop into the MVFR range as the snow
arrives on Tues morning with some periods of IFR CIGS possible
in the heavier snow bands. Winds will shift to the
south/southeast at 4 to 8 knots, except northeast at MSS on
Tuesday.
Outlook...
Tuesday Night: MVFR/IFR conditions possible. Chance SN.
Wednesday: VFR. NO SIG WX.
Wednesday Night: Mainly VFR, with local MVFR possible. Chance SN.
Thursday: Mainly VFR, with local MVFR possible. Windy with gusts
to 30 kt. Chance SHSN.
Thursday Night: VFR. NO SIG WX.
Friday: VFR. NO SIG WX.
Friday Night: Mainly VFR, with local MVFR possible. Slight chance
SHSN.
Saturday: Mainly VFR, with areas MVFR possible. Chance SHSN.
&&
.EQUIPMENT...
NOAA Weather Radio station WXM-44, transmitting from Mt.
Ascutney, Vermont, on frequency 162.475 MHz is non-operational
at this time. NWS technicians have diagnosed the problem, but
repairs will likely not be able to occur for quite some time due
to circumstances beyond our control. Therefore, the time of
return to service is currently unknown. The following NOAA
Weather Radio transmitters may be able to provide service during
this outage: WWG 50 from Burke Mtn, VT at 162.425 MHz and WNG
546 from Hanover, NH at 162.525 MHz.
Equipment malfunctions at the Colchester Reef meteorological
station will likely leave it inoperable for an extended period
of time. This site is not serviced by the NWS. Technicians do
not currently have an estimated return to service for this
station. Use extra caution when navigating the broad waters of
Lake Champlain, and please contact us if you observe winds
significantly deviating from the forecast.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Winter Weather Advisory from 7 AM Tuesday to 1 AM EST
Wednesday for VTZ003>009-017.
Winter Storm Warning from 7 AM Tuesday to 1 AM EST Wednesday
for VTZ010-011-018>021.
NY...Winter Weather Advisory from 7 AM Tuesday to 1 AM EST
Wednesday for NYZ034-035.
&&
$$
SYNOPSIS...Kutikoff
NEAR TERM...Kutikoff
SHORT TERM...Kutikoff
LONG TERM...Taber
AVIATION...Taber
EQUIPMENT...Team BTV
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