243
FXUS61 KBTV 132350
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
650 PM EST Sat Dec 13 2025

.SYNOPSIS...
A clipper passing to our north and upper level low over the
Great Lakes will bring some light snow through the weekend, with
locally heavier snow in parts of northern New York and in
higher terrain. More light snow is expected for later Monday
into Monday night. A warming trend will lead to the potential
of mixed precipitation types towards the end of the week.

&&

.NEAR TERM /THROUGH SUNDAY NIGHT/...
As of 133 PM EST Saturday...
* Locally gusty, heavy snow showers this afternoon in western
  St. Lawrence County. Otherwise, very light snow tonight into
  early Sunday, followed by upslope, northwest flow type of
  light snowfall for Sunday night.

A busy period through Sunday night with regards to at least some
chances of snow associated with three different systems in which
heavier precipitation will be south of our area for a change. The
only heavier type of snow is occurring at the time of this writing
as we track a large, convective line of snow showers that is
entering St. Lawrence County this afternoon. Upstream observations
show brief reductions to a 1/4 mile visibility, and the fairly sharp
reflectivity gradient suggests rapid changes in conditions with this
likely snow squall. Progged CAPE in the 25 to 75 J/kg range will be
supportive of snow squalls as the line moves into central portions
of the county, such as in Potsdam. Thereafter, instability will tend
to decrease along with the low level theta-e gradient becoming less
well defined, such that an organized snow squall threat will
diminish moving into the Adirondacks.

Elsewhere, as we often see on convective days there has been a large
area of very light snow blossoming with a fresh coating of snow
expected for most of Vermont and the remainder of northern New York.
This snow will tend to diminish this evening, hanging on last in
northeastern Vermont. Thereafter, we`ll see another round of light
snow develop, this time associated with mid-level deformation on the
northwest flank of the low pressure system passing well to our south
and east. Because of the large scale upper level divergence tied to
the intense upper level low over the Great Lakes, we might be able
to squeeze out periods of light, accumulating snow tonight as higher
mid-level relative humidity surges northward. Best chances of this
would be during the overnight hours and across central and eastern
portions of Vermont, but it is hard to rule out any part of Vermont
seeing at least a trace of new snow through tomorrow morning.

Finally, another minor snowfall will occur tomorrow night as the
aforementioned upper level low ejects eastward and its trough axis
passes by. The resulting northwesterly flow should be able to
squeeze out snow showers which will be aided by cold low level
temperatures supportive of effective snow growth in shallow
clouds. With Froude numbers likely dropping under 0.5 at times
overnight as an inversion level develops near mountain summit
level, snow showers are expected to expand westward into the
valleys although much of the snow shower activity will be in the
foothills. QPF looks light given forcing is purely orographic
with no replenishing deeper moisture being advected in, but a
new coating to an inch of snow is plausible in the upslope areas
of the Adirondacks and Greens. This overnight period also
continues to look like the coldest weather of the next several
days, with blustery winds of 10-15 MPH supporting wind chills
in the single digits to teens below zero.

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
As of 133 PM EST Saturday...
* Below normal temperatures with mainly light snow showers
  Monday night

Aside from some lingering snow showers, Monday continues to
look cold and dry initially. Late in the day we continue to
expect snow to develop in northern New York as the next
shortwave trough comes in from the northwest. With no surface
reflection, this system won`t have much to work with regards to
precipitation amounts. Compared to the system we`re seeing
today, thermal and pressure gradients are lackluster so even
less organized precipitation is anticipated, but at least some
light snow is probable areawide Monday night aside from perhaps
southeastern Vermont. The one area of possibly heavier snowfall
rates will be related to a modest lake band expected to develop
off of Lake Ontario, which could poke into our far southern
portions of northern New York before winds upstream turn
westerly and the precipitation shifts to our south. If the west-
southwesterly flow lingers a bit longer, snow amounts currently
forecast in the coating to an inch range could be a bit higher,
including areas farther downwind in the Adirondacks and central
Green Mountains. It will remain below normal temperature-wise,
with temperatures only recovering into the middle 10s to low
20s, but with light south winds and cloudiness overnight, Monday
night won`t be much colder than the daytime.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 1258 PM EST Saturday...The weather pattern stays pretty active
through much of next week. We`ll see a brief stint of ridging
Tuesday/Tuesday night, so outside of a few lingering mountain snow
showers during the morning hours, it should be dry. Low pressure
will slide by to our north on Wednesday, dragging a couple of fronts
across our region. The result will be another round of showers,
along with temperatures warming into the mid/upper 30s. So while the
mountains should generally remain snow, the wider valleys will
likely mix with or change to rain during the afternoon. Highest
chances for precipitation will remain in northern areas, closest to
the best forcing. More widespread precipitation then arrives later
Thursday through Thursday night. There are still differences in
model solutions with the timing/placement of this low pressure
system and its associated fronts, but overall trend continues to
keep the main low well to our north, with strong warm air advection
occurring later Thursday into Thursday night, followed by a sharp
cold front sometime on Friday. Have stayed close to the NBM for now
given the continued model differences, but expect temperatures to
warm into the upper 30s/low 40s, allowing snow to change over to
rain for just about all but the highest elevations sometime Thursday
evening/night. Considering how cold we`ve been, there are concerns
that there could be a prolonged period of a wintry mix of
snow/sleet/freezing rain before the changeover to rain, especially
in the usual sheltered locations east of the Greens. We`ll continue
to monitor trends heading forward, and would recommend our partners
and the public to do likewise, especially if travel is planned later
Thursday/Thursday night. Regardless, colder air comes rushing back
in Friday, changing precipitation back over to snow as it tapers to
showers heading into the weekend.

The other concern with this active pattern will be gusty winds. With
several frontal passages, there are indications of strong low-level
jets and the potential for these to mix down to the surface. At this
point, Thursday looks to be the windiest day, with south winds
gusting to 30 mph or more, especially in the Champlain Valley and
the northern slopes of the Adirondacks. However, south winds also
look to be gusty on Wednesday, followed by blustery west winds on
Friday once the cold front moves through. This combined with
precipitation, especially if we get any significant snow and/or
freezing rain accumulation, could be impactful to both travel and
utilities.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
Through 00z Monday...Currently, conditions are VFR, though with
MVFR ceilings at KRUT. Snow showers are currently tracking into
the Champlain Valley and could affect KBTV in the next hour.
However, it is expected to be limited as better forcing moves
north while snow showers pull away from the relatively warm
waters of Lake Champlain. South to southwest winds at 6 to 11
knots will trend towards 5 knots or less or even variable as
flow begins shifting to the west and northwest. About 06z, some
very light snow will lift up from the north. Areas like KRUT and
KSLK will see ceilings fall towards 2500 ft agl. KRUT is the
most likely to see light snow and noted 3SM. There is lower
confidence for KSLK, KBTV, and KMPV, and so have posted a PROB30
given uncertainty how far north snow makes it. Light snow will
pivot back southeast as a boundary continues farther south about
15z, with northwest winds increasing to 5 to 9 knots, and this
will also bring improving ceilings. After 22z, winds will become
5 knots or less.

Outlook...

Sunday Night: VFR. Slight chance SHSN.
Monday: VFR. Chance SHSN.
Monday Night: Mainly VFR, with areas MVFR possible. Chance SHSN.
Tuesday: Mainly VFR, with local MVFR possible. NO SIG WX.
Tuesday Night: VFR. NO SIG WX.
Wednesday: Mainly MVFR, with areas VFR possible. Chance SHSN,
Chance SHRA.
Wednesday Night: Mainly MVFR, with areas VFR possible. NO SIG WX.
Thursday: VFR. Chance RA, Slight chance SN.

&&

.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...None.
NY...None.

&&

$$
SYNOPSIS...Kutikoff
NEAR TERM...Kutikoff
SHORT TERM...Kutikoff
LONG TERM...Hastings
AVIATION...Haynes
EQUIPMENT...Team BTV