463
FXUS61 KBTV 281740
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
1240 PM EST Fri Feb 28 2025

.SYNOPSIS...
Scattered snow showers early today will be followed by clearing
skies as colder air returns. A clipper system racing eastward
will bring another period of widespread snow tonight, followed
by milder conditions in the morning with more scattered snow
showers. Much colder air again will return late Saturday with
frigid conditions expected for Sunday through early Monday. The
brief cold snap will give way to a thaw in the middle of next
week.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of 1230 PM EST Friday...Minimal changes needed to the
forecast with this update, with a fairly pleasant afternoon
shaping up across the region ahead of our next system arriving
tonight. Lots of blue sky can be seen this afternoon, with high
clouds expected to overspread in the next few hours.

Previous Discussion...
Very active weather will occur through the next 36 hours: there
will be two frontal passages with sharp cooling, and in between
a clipper will bring both steady snow and convective snow
showers with moderating temperatures. A Winter Weather Advisory
has been continued for much of northern New York for the 4 PM
Friday through 7 PM Saturday period where greatest impacts are
expected. While snowfall amounts have trended downward slightly
in this region, there were no significant changes in the
forecast. New snowfall generally across Vermont and northern New
York will average 2 to 5 inches for most locations.

For early this morning, ongoing snow showers with localized snow
squalls are expected to exit as skies clear rapidly from west
to east. With shallow moisture and a relatively warm cloud layer
with west-southwest flow, the precipitation will be mostly in
the higher terrain or in the western foothills. Gusty winds
locally upwards of 40 MPH are possible as well, but the stronger
winds will largely occur where little or no new snowfall occurs
in the lee of the higher terrain. Temperatures will be falling
behind the cold front this morning with most locations seeing
their highest temperature early this morning. Daytime
temperatures will generally be in the teens and twenties with
lowest wind chills this morning before winds quickly subside
this afternoon.

Tonight snow will quickly overspread the region from west to
east, with arrival trending slightly slower such that only a
late evening commute would be impacted. Snow onset generally
looks between 6 and 9 PM, with moderate intensity of up to 0.5"
per hour likely. The steady snow may only last 3 to 6 hours for
most of the region, which is a limiting factor to snowfall
amounts. This burst of snow will probably have average snow
character between dry and wet, but trend towards wet before it
ends.

Additional scattered snow showers then will quickly
develop as we get under the warm sector of the clipper system.
There is uncertainty in the low track which will have
implications for our weather Saturday morning, especially in
western portions of northern New York which could see winds stay
northeasterly with cold air locked in and more steady snow. The
consensus low track seems to have shifted well north with the
latest data, which has led to a change from snow to rain in
portions of the southern St. Lawrence Valley before the cold
front passes. A 40 knot 850 millibar southwesterly jet Saturday
morning out ahead of the low will largely minimize precipitation
in the Champlain and Connecticut River valleys, but any
precipitation there would also be rain during the morning. Snow
showers during the morning will have ample instability and
frontogenesis to produce intense snowfall rates, although a
limiting factor, similar to early this morning, will be depth of
moisture relative to the dendritic snow growth zone.

That being said, very strong low level vertical motion and
indications of scattered, heavy showers in various CAMs are
consistent with high snow squall parameter values tomorrow
morning shifting eastward along the front, exiting Vermont
quickly during the early afternoon. Additional snowfall amounts
could be quite variable during this stage of the event given the
nature of convection, and also should be elevationally
dependent. Lower elevations across the region should see
temperatures rise above freezing ahead of some of these snow
showers, with accumulations limited by warm surface
temperatures. Combination of wet bulb cooling and cold air
advection could lead to rapid temperature falls below freezing
that may be capable of localized flash freeze conditions, but
there is a low chance of more widespread impacts that would be
associated with a more organized, linear snow squall event. Any
additional snow showers behind the front would be increasingly
powdery, as lower water content snow would be favored with
thermal profiles cooling dramatically near the surface. These
showers will be more confined again to the western foothills of
the Adirondacks and northern Greens as the upper level trough
swings through. Temperatures will vary greatly through the day.
Temperatures during the morning will be falling back into the teens
from the Adirondacks westward while still in the thirties
across Vermont, where temperatures will fall sharply as the
afternoon progresses.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 339 AM EST Friday...Upslope snow showers will persist through
the first half of Saturday night as the aforementioned cold front
continues to traverse the region with additional snow accumulations
of a dusting to 2 inches. Strong cold air advection, 925mb temps
dropping to -20-25C and a well mixed lower atmosphere will result in
a blustery and cold night with overnight lows a good 10 degrees
below normal in the single digits above and below zero. And with
winds gusting as high as 20-30 mph, wind chills may approach
advisory levels of -20F early Sunday morning.

A cold day follows for Sunday as high pressure settles overhead with
925mb temps warming only into the mid/upper teens below zero
supporting surface highs only in the single digits and teens above
zero. Winds slacken through the day, so wind chills won`t be quite
so bad. Clearing skies and abating winds through the afternoon and
into the overnight then set the stage for a very cold Sunday night
with the entire CWA expected to fall below zero. Wider valleys will
just fall into the single digits below zero, while elsewhere teens
below are likely. Additional cold headlines may be needed as winds
may not go completely calm, and wind chills may fall below -20F.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 339 AM EST Friday...As high pressure begins to shift east of
the region, temperatures will begin to rebound Monday, but only into
the 20s under partly sunny skies. Further warming is expected
Tuesday into the mid/upper 30s as the high moves off the eastern
seaboard and south/southwesterly winds increase as the pressure
gradient tightens between the exiting high and our next low pressure
system developing over the Mississippi River Valley. Some spotty
warm air advection precipitation is possible Tuesday though the bulk
looks to be more closely tied to the approaching low.

Model consensus is strong with the track of this next system moving
from the Mississippi Valley Tuesday to the Ohio Valley Wednesday,
and through the Ottawa Valley Wednesday night into Thursday. This
puts the North Country and Vermont on the warm side of the system
with Wednesday and Thursday highs expected to be well into the 40s.
PWAT anomalies are off the charts; 3-4 standard deviations above
normal, but the good news is the system appears to be weakening as
it lifts out of the Ohio Valley. This limits the amount of forcing
over our region, and overall probabilities for QPF are highest
around 0.5" with very few ensemble members showing anything close to
1" from Wednesday through Thursday. 1-2 days of above freezing
temperatures and rain support significant snowmelt which will likely
lead to river ice breakup. With current river ice thickness ranging
from a few inches to around a foot, and most rivers exhibiting near
100% closed channels, ice jam flooding is not expected at this time,
but certainly some channels will begin to open and ice movement is
possible.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Through 18Z Saturday...VFR conditions currently prevail across
the region this afternoon, with the exception of some MVFR
ceilings at KEFK. VFR conditions are expected to prevail for the
next several hours, until widespread snowfall arrives towards
00Z, bringing a period of MVFR and IFR visibilities to terminals
overnight. The steadiest snowfall should end between 06Z and
09Z, with some light snow showers possible beyond this. Ceilings
will gradually lower as precipitation begins, with MVFR ceilings
expected for the later half of the forecast period. Winds are
generally northwesterly between 10-15 knots, with gusts up to 25
knots this afternoon, and will become southerly towards 00Z and
becoming increasingly gusty towards 06Z. A period of LLWS is
expected at all terminals between 00Z and 12Z.

Outlook...

Saturday Night: VFR. Chance SHSN.
Sunday: VFR. NO SIG WX.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. Chance SHSN, Chance SHRA.
Tuesday Night: Mainly MVFR, with areas VFR possible. Chance SHRA,
Chance SHSN.
Wednesday: Mainly MVFR, with areas IFR possible. Definite SHRA.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...Winter Weather Advisory from 4 PM this afternoon to 7 PM EST
     Saturday for NYZ026-027-029>031-034-087.

&&

$$
SYNOPSIS...Kutikoff
NEAR TERM...Kremer/Kutikoff
SHORT TERM...Lahiff
LONG TERM...Lahiff
AVIATION...Kremer