523
FXUS61 KBTV 231734
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
1234 PM EST Sun Feb 23 2025

.SYNOPSIS...
Light snow is ongoing across much of the region, but it will
gradually become less widespread and more confined to the mountains
as the morning progresses. Totals will range from a dusting in the
valleys to 2 to 4 inches across the northern Adirondacks and
northern Green Mountains. The warming trend will continue for the
next couple days, with highs well reaching above freezing by
Tuesday. There will be a few chances of light precipitation this
week, but no big storms are expected.

&&

.NEAR TERM /THROUGH MONDAY/...
As of 1226 PM EST Sunday...Web cams and radar imagery continues
to indicate light snow shower activity across the mtns of
northern NY into central/northern VT. Have continued with likely
to cat pops acrs these areas with another inch or so possible
thru the rest of today. As expected temps have been struggling
to warm much under modest caa and plenty of clouds. We have
nudged to 33 here at the airport, but many areas remain in the
mid 20s to lower 30s. Expect another degree or two this aftn
with highs in the upper 20s to mid 30 range. No significant
changes made to crnt fcst.

Previous Discussion...A weak clipper is causing light snow
across much of northern New York and the mountains of Vermont.
In Vermont, critical flow is causing the most snow to fall over
the spine of the Greens and areas slightly to the east like
Morrisville and Stowe. The snow will continue relatively
consistently for the next few hours before it decreases in
coverage throughout the morning as the best synoptic forcing
passes to the east. In total, a few inches are expected in the
most favored areas. Downsloping is keeping the snow out of the
Champlain and Connecticut River Valleys and this will continue.
A few lingering snow showers will continue in the mountains
during the day but those are not expected to cause much in the
way of accumulations. During the afternoon, as a weak cold front
tries to dip south into the region, a few light convective snow
showers are possible over northern areas. There is mixing to
around 5,000 feet and a little instability.

Warm advection on southwest flow has been keeping temperatures
elevated during the night, with lows in the 20s in most places.
Temperatures are expected to rise into the upper 20s and 30s today
under continued warm air advection. Late in the day, on the backside
of the clipper, flow becomes westerly before it weakens overnight.
While any cold air advection will be very minimal, partial clearing
and calm winds should allow temperatures to drop tonight,
particularly in the protected hollows east of the Greens. Currently
have lows in the teens in most places, though they should be in the
single digits in parts of eastern Vermont. Clearer than expected
skies will cause temperatures to fall farther, while more clouds
will keep them much higher. Southwest flow will develop in the St.
Lawrence Valley and temperatures there may stay in the 20s.

On Monday, a strong low will pass over the Hudson Bay and stay to
the north, deepening below 980 mb. It will help create a strong
pressure gradient, causing gusty southwest winds to develop as the
day goes on. A 50-60 KT low level jet is expected to pass overhead
late in the day and into Monday night, peaking with 50-60 KTs down
to around 3,000 feet. Profiles are suggesting that mixing will not
be the most efficient, so keeping gusts in the 25-35 KT range for
now. Light precipitation should move into some of the northern areas
late in the day, but trends are continuing to keep it farther and
farther north, and most is now expected to stay over Quebec. Strong
downsloping will keep this out of the Champlain Valley. The
precipitation type will be elevation dependent, but with amounts
being so light, not expecting much of anything in accumulations or
rainfall.

&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY/...
As of 354 AM EST Sunday...During the nighttime hours Monday into
Tuesday, a prefrontal trough will slide east coincident with an
upper vort passing north of the international border. The best
forcing is not aligned with better moisture, which will have pushed
east into Maine while the trough moves overhead. This forecast has
trended precipitation chances and amounts down as a result. Outside
of northern New York and the Northeast Kingdom of Vermont where a
few hundredths will be possible, much of the region will likely
avoid measurable precipitation. South flow and abundant cloud cover
will likely keep most of the region in the 30s, except areas over
2500 ft elevation that should remain below freezing.

During the day on Tuesday, we will see temperatures slowly warm as
south flow continues ahead of a surface cold front into the upper
30s to mid 40s. However, the cold front appears likely to wash out
while an upper vort passes overhead around noon. The combination of
weak flow, temperatures above freezing, and a well established
snowpack may result in a foggy-over-snow day with low clouds across
the region. Forecast soundings indicate the best moisture will
mainly reside below 750mb with the DGZ above 700mb. With the
presence of the weak trough and subtle warm advection, this could be
a situation where we are dealing with drizzle as opposed to rain.
Mountain summits above 3000 ft elevation should still be below
freezing. So it could still be snow or rime at our high peaks. These
things are hard to suss out beyond 48 hours, so will let this
marinate and see how things look as we get a bit closer.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
As of 354 AM EST Sunday...A really narrow ridge will briefly build
Tuesday night into Wednesday. With the cold front washing out before
it crosses, it will be another warm night and day running 10-15
degrees above normal with lows around the 30s and highs in the upper
30s to mid 40s. The day could start with elevation dependent light
drizzle/rain or light snow showers, but mainly dry much of
Wednesday.

Forecast guidance diverges a great deal past 00z Thursday. For
example, within the NBM, the temperatures spread between the 25th
and 75th percentile at BTV ranges between 15 and 25 degrees, most
notably Wednesday night. It will be on account of 3 shortwaves that
will traverse the region between 12z Thursday and 12z Friday. Where
they track or how they interact will determine the placement of cold
air. Despite the chaotic upper flow, there will be a fairly compact
1000mb surface low tracking near the area, which should overspread
precipitation across the region. The best chances for precipitation
will be just north of the surface low. So if it tracks north, then
areas south may miss out, and so the axis of highest PoPs is
positioned along the international border. Overall, guidance has
trended warmer, but with larger potential forecast variability,
remained very close to blended data for now in representing valley
rain and mountain snow. Behind the system, the switch to northwest
flow will provide some backside snow as cold air rushes into the
region.

After a cool Friday night/Saturday morning, Saturday afternoon will
quickly warm as a longwave trough amplifies to our west driving
strong return flow. A weakening surface low around 990mb appears
likely to track just north of Montreal, which will produce scattered
rain or snow showers depending on elevation. Then, temperatures
appear likely to trend well below normal with an incursion of arctic
air as the amplified longwave trough moves overhead. So don`t get
too used to the warmer temperatures, because it appears March will
open up quite chilly behind this system.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Through 18Z Monday...Snow showers continue per web cams and
radar imagery across our mountain taf sites with vis ranging
between 2-5SM, while valleys are mostly VFR. Expect occasional
snow showers to prevail at SLK/EFK thru 00z with intervals of
IFR vis likely from time to time. Elsewhere, mostly VFR
conditions with brief periods of MVFR vis/cigs associated with
passing snow showers, especially at MSS/MPV. Conditions slowly
improve to a mix of MVFR mtns to VFR valleys by 06z with VFR by
12z Monday at most sites. Winds remain from the west/northwest
at 5 to 10 knots today and become light trrn driven overnight,
before shifting to the south/southeast at 5 to 15 knots on
Monday with localized gusts 15 to 20 knots possible.

Outlook...

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

&&

.EQUIPMENT...
The Mount Ascutney NOAA Weather Radio transmitter, serving
portions of eastern Vermont, is currently out of service. The
earliest date of restoration is now Tuesday, February 25th
following a delay. We apologize for any inconvenience.

&&

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

&&

$$
SYNOPSIS...Myskowski
NEAR TERM...Myskowski/Taber
SHORT TERM...Haynes
LONG TERM...Haynes
AVIATION...Taber
EQUIPMENT...WFO BTV