184
FXUS61 KBTV 240714
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
214 AM EST Mon Nov 24 2025
.SYNOPSIS...
Light upslope snow will taper off today with a dry period
expected through much of Tuesday as temperatures trend a bit
higher. A warm front will bring light rain late Tuesday and
even milder conditions for Wednesday, especially immediately
ahead of a cold front. This front will pass through Wednesday
night, which will promote showers and blustery conditions into
Thanksgiving Day. Gusty winds will continue Thursday night
through Friday along with localized lake-effect snowfall and
then quieter, drier weather will follow for the weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 213 AM EST Monday...We`re on the backside of a broad
shortwave trough this morning, and spokes of deeper moisture are
pivoting eastward before it exits. Most of this activity is
focused in southern portions of the region; however, subtle
surface troughs are helping precipitation blossom in the
Champlain Valley and northeastern Vermont, and as low level flow
becomes more westerly finally after sunrise there will be a
more pronounced upslope precipitation event unfolding rather
than the more chaotic coverage of snow showers currently on the
map. Steep lapse rates and orographic lift should overcome lack
of large scale lift and poor saturation of the snow growth zone
to provide at least a couple hours of light snow accumulations.
As the snow showers wind down from late morning through early
afternoon, we`ll probably see only up to an inch in most
locations in the Adirondacks and northern Vermont, and possibly
1 to 2 inches on the mid-slopes and summits of the central and
northern Greens.
The weather pattern will change pretty significantly into
tonight as much milder air aloft advects into the area on
west/southwest flow as surface high pressure passes to our south
and east. Warm frontal precipitation mainly to our north could
briefly swipe northern Vermont at some point tonight with very
light snow as it falls into a dry near surface layer, but
otherwise it will remain dry with temperatures steady and then
rising a bit overnight as winds aloft increase greatly,
supporting mixing of warmer air above the surface following
sunset. Think low temperatures are somewhat uncertain, with
areas in central and eastern Vermont especially so where
presence of clouds and/or wind would lead to a milder night than
currently indicated.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
As of 213 AM EST Monday...Mild conditions will be in place on
Tuesday, along with breezy, southerly channeled flow on Lake
Champlain where a lake wind advisory may be needed at the start
of the period. As a wave of low pressure approaches from the
Ohio Valley, rain chances will increase, especially after
sunset. Have indicated a slight chance of freezing rain at this
time in possible colder pockets in northeastern Vermont, but
confidence in accumulating ice at this time is low, given
expected temperatures well above freezing during the day Tuesday
and poor radiational cooling out ahead of the precipitation.
Perhaps some locations will wet bulb down to near freezing, but
think this event will be mainly plain rain. In fact, beginning
Tuesday evening and lasting through all of Wednesday, even
mountain summits will be all rain as a deep warm layer will
cause the freezing level to be well above 5,000 feet. The main
period of rain, with light amounts averaging in the range of
0.15" to 0.35", will be overnight Tuesday.
This widespread rain will be followed by widely scattered
shower activity during the day on Wednesday in a warm sector of
a large frontal system that will drag a cold front into the area
at the end of the day. High temperatures for Wednesday have
edged slightly warmer, likely associated with the system
trending stronger and the related warm air advection being more
substantial out ahead of the cold front. 925 millibar
temperatures will become anomalously warm, possibly pushing the
98th climatological percentile in Vermont towards Wednesday
evening. Moist low level air will keep us from seeing equally
anomalous surface temperatures associated with better mixing.
That being said, future forecasts may need to bump up high
temperatures further, especially east of the Green Mountains
where non-typical diurnal temperatures (rising after sunset)
are expected.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 1252 AM EST Monday...Lake effect snow will get underway as deep
southwesterly flow sets in until a vigorous upper vort pushes east
of the region. Warm surface conditions and very cool upper
temperatures in the 10th percentile will result in scattered
precipitation, even without the band of lake effect that will
develop. Low-level cold advection doesn`t begin until Friday. So
there will be some valley rain where temperatures will rise into the
upper 30s to near 40 on Thanksgiving Day. The lake effect showers
will be active Wednesday night into Thanksgiving morning across the
St. Lawrence Valley, and then as diurnal instability of about 100
J/kg with 8-9 C/km lapse rates will develop, that scattered activity
will develop across Vermont. Thanksgiving Day will be breezy with
gusts 25 to 35 mph across the area, less breezy in the Upper Valley
into the Northeast Kingdom to just 20 mph.
Thanksgiving night into Friday, a surface trough will progress east,
and flow will turn more westerly. The lake effect band will amble
southwards. Then the backside of the upper trough will shift
southeast Friday afternoon, switching activity to more orographic
northwest slope type snow. Between this and the lake effect snow,
we`ll need to monitor the potential for headlines. Probabilistic
data suggests a 50-70% chance of about 8" of snow in far southern
St. Lawrence County over a 48 hour period. We`ll certainly know more
as high res, convective allowing models can capture these details
better.
This activity appears somewhat short-lived as channeled zonal flow
aloft and incoming 1030+mb high pressure ambles overhead, which will
cause precipitation to diminish. Saturday night into Sunday could be
quite chilly if we manage to clear out. Southwesterly return flow
becomes reestablished fairly quickly, and we`ll warm back up heading
into the new work week.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Through 06Z Tuesday...Lingering light rain or snow and northwest
flow as a weak trough shifts east will result in continued mix of
MVFR to IFR conditions, mainly at KSLK. By about 11-13z, snow
showers will wind down, and then ceilings will gradually improve.
Outside KSLK, all sites should be VFR by about 19-21z. Winds will be
southwest to northwest at 5 to 9 knots through the period.
Approaching 06z Tuesday, winds at 2000 ft agl will begin to
increase. Some areas of LLWS could reach KMSS by then.
Outlook...
Tuesday: VFR. Chance RA.
Tuesday Night: MVFR/IFR conditions possible. Chance RA.
Wednesday: Mainly IFR, with areas MVFR possible. Chance RA.
Wednesday Night: Mainly VFR, with local IFR possible. Definite
RA, Chance SN.
Thanksgiving Day: Mainly VFR, with local MVFR possible. Chance
SHRA, Chance SHSN.
Thursday Night: Mainly VFR, with local MVFR possible. Chance
SHSN.
Friday: Mainly MVFR, with areas VFR 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.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Kutikoff
NEAR TERM...Kutikoff
SHORT TERM...Kutikoff
LONG TERM...Haynes
AVIATION...Haynes
EQUIPMENT...Team BTV
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