117
FXUS61 KBTV 130640
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
240 AM EDT Fri Mar 13 2026
.WHAT HAS CHANGED...
As of 237 AM EDT Friday...
No significant changes were made to the current forecast.
&&
.KEY MESSAGES...
As of 237 AM EDT Friday...
1. A clipper system will bring up to 6 inches of snow to some
locations late today into early Saturday.
2. Gusty winds will accompany a clipper system tonight into
tomorrow.
3. A strong system will impact the region late Sunday through
Monday night.
4. Cool weather returns midweek with some snow showers possible.
&&
.DISCUSSION...
As of 237 AM EDT Friday...
KEY MESSAGE 1: A clipper type system will move through the region from
west to east this late this afternoon into Saturday morning. Snow
showers are expected to arrive across northern New York beginning
this afternoon, continuing overnight, as showers spread east into
Vermont. A Winter Weather Advisory is in effect from 2 PM this
afternoon until 1 PM Saturday for the Adirondacks in northern New
York, as well as for the southern Greens where up to 6 inches of
snow is possible. Higher snow amounts are expected in the
Adirondacks with amounts ranging from 3-6", locally higher on
mountain summits. Probabilities of exceeding 4" is mainly maximized
over the Adirondacks at 50-70%. An initial warm front will bring
good waa aloft with a brief surge in 850-700mb frontogenesis
supporting brief light to moderate snow. However, given marginal
temperatures in the low to mid 30s, even with some wet bulbing, some
areas of rain are possible across the St. Lawrence and Champlain
Valleys as well as across southern Vermont.
The limiting factor to this system remains low QPF and the surface
low track. Total QPF is only forecast to be between 0.1-0.4" as the
system does not favor good moisture connections. Moderate 14-16:1
snow ratios should help inflate totals a little with lower QPF, but
high snow amounts are unlikely with this system. The low is expected
to pass over the northern St. Lawrence Valley and ride along the
International Border. These tracks favor shadowing in the Champlain
Valley and eastern Greens, with higher amounts favored along the
western facing slopes of the Adirondacks and Green Mountains.
Locations above 2000ft in the Greens could see locally higher than 6
inches of snow. Outside of summit levels and the Advisory areas, a
dusting to locally 3 inches of snow is expected. The timing of the
snow this afternoon/evening could impact the Friday evening commute
with a quick burst of 1-2" of snow across northern New York and near
the Green Mountains. The timing of the heaviest snow will be between
8 PM this evening and Midnight Saturday. The snow will become more
showery and confined to the higher terrain and western facing slopes
by Saturday afternoon where a few additional inches may be possible
as northwest flow supports upslope snow showers. Snow showers will
taper off entirely across the region Saturday night.
KEY MESSAGE 2: In addition to the snow component of the clipper type
system today into tomorrow, winds will become gusty tonight into
tomorrow. As a warm front lifts to the northeast late this evening,
winds will become southerly with steepening lapse rates.
Furthermore, the surface low will be deepen as it moves through the
region, enhancing the isallobaric wind component. This enhancement,
coupled with channeled southerly flow and a LLJ of 50-60kts, winds
could briefly gust up to 30-40 MPH this evening in the Champlain
Valley and in the south-north oriented valleys of eastern Vermont.
As the low shifts east, winds will shift to the west by tomorrow
morning which should briefly weaken gusts. However, once winds reach
the west, downsloping will re-enhance gusts back towards 25-35 MPH
east of the Adirondacks and Green Mountains. The surface low will
continue to track east, well away from the region Saturday night
weakening the pressure gradient and subsequently trending winds
towards more calm conditions by Sunday morning.
Have continued to trend towards the NBM90th with gusts this evening
and tomorrow, but trends have mostly stabilized with values
remaining under wind advisory criteria at this time. All said, tree
branches could be broken with these gusty winds, but strong winds
are not expected at this time.
KEY MESSAGE 3: Sunday will begin quiet and cool. Surface high pressure
will shift offshore, and then a deep layer ridge will expand across
the northeastern US. The way precipitation arcs over the ridge axis
leaves a narrow axis of moisture within a region of broader dry air
within the warm sector of approaching low pressure. This may be a
boon, as it could allow for us to simply see some snow that lifts
north of the border with little precipitation on the backside due to
dry entrainment, and we could then avoid a transition to a broader
mixed precipitation event. Still, in case precipitation is slow to
exit, indicated slight chance to chance for sleet and freezing rain
from the northern Champlain Valley westwards.
After a short interval of drying Sunday night, a plume of moisture
will lift north from the Atlantic. Cool, sheltered hollows of
eastern Vermont may remain below freezing, and some freezing rain is
forecast along the New Hampshire border on Monday morning. Mid-
morning to early afternoon, cooler air should begin to mix out and
eastern Vermont will transition to all rain, while the Atlantic
moisture plume shifts eastwards.
More impactful Sunday night through Monday afternoon will be the
arrival of 850mb south winds of 55-65 knots. Strong surface heating
to the mid 50s to mid 60s in the warm sector will promote the
potential for the mixing of these winds for favorable areas within
the northern Champlain Valley and northern slopes of the
Adirondacks. The forecast indicates wind gusts in these areas rising
to 45 to 50 mph. South winds are typically less impactful as most
trees are acclimated to these conditions, but thawing soils may
leave things a bit looser at this stage.
For Monday afternoon and evening, there will be a strong cold front
moving east. Like 24 hours ago, low resolution global models already
depict a line of heavy rain tracking east. Although noting the
potential in some of these scenarios that convection may develop
well south of our area, and strong unidirectional meridional flow
with ample warm advection brings stratiform off that convective
activity. There may also just be some shower activity with a range
of elevated or MUCAPE depicting about 100-250 J/kg of instability.
The front itself will cross near and after sunset with a sharp wind
shift and quickly falling temperatures. Depending on how much
moisture remains, some snow may mix in with lingering showers. The
upper vort is still nearby, and so with the south-southwest flow,
perhaps pockets of lake effect may even develop Monday night.
KEY MESSAGE 4: Conditions will become cooler behind the strong front.
The weather pattern returns to something a bit more characteristic
of this winter season with troughing in the eastern US returning.
Weak disturbances could produce some snow showers here and there.
We`ll have to watch surface temperatures, as the better sun angle
means we see temperatures rise into the mid 30s to lower 40s.
However, warm air is shallow enough, then we can observe snow
showers in spite of temperatures in the mid-upper 30s.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
Through 06Z Saturday...Conditions are a mix of MVFR and VFR.
Stratocumulus with bases around 2000-3000 ft agl are the main cause.
Some snow showers are still lingering in northwest flow of 5 to 12
knots, but dry air is resulting in little reductions to visibility
within snow showers. A few PROB30s were highlighted to indicate a
low chance for MVFR visibility. After 10z-12z, snow showers will
diminish and flow will become increasingly variable. Clouds will
briefly scatter. Winds will then shift to the south to southeast
ahead of the next system and high clouds move in from the southwest.
Snow will start to edge northeastwards about 21z-03z across the
region. There is some uncertainty on the timing of when the initial
snow decays and a stronger band of snow behind it more produces
greater visibility reductions, and so mainly stuck to 3SM -SN,
except taking it to IFR at KMSS where there`s greater confidence. As
snow arrives, winds will begin to increase towards 7 to 13 knots
sustained with gusts 15- 23 knots possible, with northeast flow
beginning at KMSS as low pressure approaches towards 00z Saturday.
Outlook...
Saturday: Mainly MVFR, with areas VFR possible. Windy with gusts
to 30 kt. Chance SN, Chance RA.
Saturday Night: VFR. Windy with gusts to 30 kt. Slight chance SN.
Sunday: VFR. Windy with gusts to 30 kt. Chance SN, Chance RA.
Sunday Night: Mainly VFR, with local MVFR possible. Windy with
gusts to 35 kt. Chance RA, Chance SN.
Monday: Mainly MVFR, with local IFR possible. Windy with gusts to
30 kt. Definite RA.
Monday Night: Mainly MVFR, with areas IFR possible. Windy with
gusts to 30 kt. Definite RA, Chance SHRA, Chance SHSN.
Tuesday: Mainly VFR, with local MVFR possible. Slight chance
SHSN.
&&
.EQUIPMENT...
The Colchester Reef meteorological station is out of service.
This site is not serviced by the NWS and there isn`t an
estimated return to service at present. Please contact us if you
observe winds significantly deviating from the recreational
forecast.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Winter Weather Advisory from 2 PM this afternoon to 2 PM EDT
Saturday for VTZ019-020.
NY...Winter Weather Advisory from 2 PM this afternoon to 2 PM EDT
Saturday for NYZ029-030-034.
&&
$$
WHAT HAS CHANGED...Danzig
DISCUSSION...Danzig/Haynes
AVIATION...Haynes
EQUIPMENT...NWS BTV
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