000
FXUS61 KBTV 242355
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
655 PM EST Fri Jan 24 2020

.SYNOPSIS...
A low pressure system will bring messy weather to the North Country
over the weekend with a mix of wintry precipitation. A Winter
Weather Advisory is in effect from 1PM Saturday to 4AM Sunday
for parts of the North Country due to light ice accumulations,
which may impact travel. Temperatures will cool following the
departure of the low, leaving mountain snow showers in it wake
throughout the beginning of the week. Showers will cease
Wednesday and quiet weather is in store for the remainder of the
week.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of 654 PM EST Friday...Overall forecast in good shape and
only minor tweaks needed at this time. Satellite trends indicate
less cloud cover over the area this evening and this should be
the case for the next several hours before mid and high level
clouds move in along with some lower clouds across southeast
Vermont and the Saint Lawrence Valley of New York. When the
lower clouds do move in there may be a little light freezing
drizzle associated with these clouds and have continued this
idea in the forecast. Rest of forecast remains unchanged.

Previous Discussion...
Currently, surface high pressure is situated off the coast of
New Brunswick and departing eastward. Meanwhile, a vertically
stacked low pressure system is approaching from the southwest.
This will induce easterly flow at the surface, allowing low
level moisture to be trapped along the east side of the Greens
and channeled down the St. Lawrence Valley. Consequently, low
clouds will develop within these regions, and patchy freezing
drizzle is likely during the overnight hours despite being dry
aloft. Thus, roads may be slick at times. The additional cloud
cover will keep overnight low temperatures moderate across
southeastern VT (upper 20s), while elsewhere lows will be in the
low 20s.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/...
As of 327 PM EST Friday...A Winter Weather Advisory has been issued
beginning 1PM Saturday and continuing until 4AM Sunday for the
northern Saint Lawrence Valley, eastern Adirondacks, and central &
eastern VT due to mixed precipitation and light ice accumulation.

As the low pressure system draws near Saturday, winds will increase,
becoming southeasterly. Highs will reach mid to upper 30s under warm
air advection before the precip sets in. Model guidance is in good
agreement regarding the arrival of precip, beginning in
northern NY during the early afternoon and reaching VT by early
evening. Precip will be heaviest within the first few hours of
the onset; during this time, there is favorable synoptic ascent
paired with mid-level f-gen, low level convergence, and a strong
low level jet of 50-60kts out of the southeast. This will cause
breezy winds at the surface with gusts up to 25-35kts,
particularly along the western slopes of the Greens and
Adirondacks. In addition, areas northwest of higher terrain,
namely the Champlain Valley, portions of northern NY, and the
Northeast Kingdom, may see lesser precip due shadowing of the
southeast jet.

One of the main challenges with this system continues to be the
precipitation type. Thermal profiles are within a degree or two of
freezing at the surface and all the way up to 800mb; thus, a slight
change in the temp profiles, whether at the surface or aloft, could
significantly alter the p-type. As the forecast stands, precip will
begin as rain, with freezing rain/sleet or snow more likely across
higher elevations (>2000ft). This will continue overnight until
temperatures begin to cool aloft Sunday morning as the low lifts
northeastward. During this time, chances for precip will dwindle and
transition into a light snow/sleet mix. Winds will become
southwesterly, favoring mountain snow showers for Sunday afternoon.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
As of 327 PM EST Friday...The extended forecast will return to
relative calm. Temperatures on Wednesday could actually be near
normal. We stick with northwest flow, but without significant Arctic
air. Monday and Tuesday, low- level moisture will be lingering over
the area with weak mid to upper level perturbations keeping that
chance for snow showers. These would mainly be over the mountains.
Dry air begins advecting into the North Country on Wednesday and
winds turn westerly as a shortwave ridge moves into place. This will
dry things out completely mid-week, and we should trend a bit warmer
into the weekend.

Ensemble forecasts and deterministic solutions are in good agreement
of the 500mb height pattern. Thus, it appears quite likely a system
comes through toward the end of next weekend. There`s a northern
stream shortwave and then a stronger southern stream shortwave. What
happens with these will affect how things play out near the surface.
At this stage, it is way too early to expect model consensus, and
not surprisingly, there is none.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
Through 00Z Sunday...Mainly mid and high level clouds will exist
over the area through about 18z. The only exception to this will
be for some MVFR ceilings possibly developing at KMPV and KMSS
between 06z and 12z. There may eve be some light freezing
drizzle at these two locations with the cloud cover. Eventually
all areas will see ceilings lowering into the MVFR category
between 18z and 00z as deeper moisture moves into the region. At
the same time precipitation will also be moving in, which should
start as some light rain, but then looking at some sleet and
freezing rain mixing in, especially after 21z. Visibilities will
lower into the MVFR category with the precipitation moving in.
One other item of note will be increasing low level wind shear
at KSLK, KRUT, and KMPV as strong southeasterly winds at 2000
feet move across the area. In addition...winds at KRUT could
gust to 30 knots after 21z.

Outlook...

Saturday Night: MVFR/IFR conditions possible. Windy with gusts to
35 kt. Definite RA, Definite FZRA, Scattered SHRA.
Sunday: Mainly MVFR, with local IFR possible. Chance SHRA, Chance
SHSN.
Sunday Night: Mainly MVFR, with local IFR possible. Chance SHSN.
Monday: Mainly MVFR, with local IFR possible. Chance SHSN.
Monday Night: Mainly MVFR, with areas IFR possible. Slight chance
SHSN.
Tuesday: Mainly MVFR, with local VFR possible. Slight chance
SHSN.
Tuesday Night: Mainly MVFR, with areas VFR possible. NO SIG WX.
Wednesday: VFR. NO SIG WX.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Winter Weather Advisory from 1 PM Saturday to 4 AM EST Sunday
     for VTZ003-004-006>008-010-012-018-019.
NY...Winter Weather Advisory from 1 PM Saturday to 4 AM EST Sunday
     for NYZ026-027-030-031-034.

&&

$$
SYNOPSIS...Hammond
NEAR TERM...Evenson/Hammond
SHORT TERM...Hammond
LONG TERM...Haynes
AVIATION...Evenson