496
FXUS61 KBTV 211722
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
122 PM EDT Sat Mar 21 2026
.WHAT HAS CHANGED...
As of 258 AM EDT Saturday...
A Winter Weather Advisory has been issues for portions of northern
New York and Vermont from 8 PM Saturday through 8 AM Monday.
&&
.KEY MESSAGES...
As of 258 AM EDT Saturday...
1. Another clipper to move across the North Country and
northern New York Saturday night into Monday morning.
2. Seasonally cool and drier to start next week.
3. Active weather continues Wednesday through Friday with two
systems projected to move through the region during that time frame.
&&
.DISCUSSION...
As of 258 AM EDT Saturday...
KEY MESSAGE 1: We remain in a very active zonal longwave pattern with
periodic shortwave energy helping to develop weak surface low
pressure systems. Another one of these systems is expected to move
across the Great Lakes and towards northern New York Saturday night
with widespread snowfall expected to fall. Models continue to flip-
flop on whether the low center tracks over us, south of us, or north
of us which unfortunately has serious implications on the forecast.
The latest 00Z ensemble guidance is finally showing some clustering
with the low center tracking south of our forecast area. For us,
that would lead to a more widespread snowfall event with some rain
mixing into the wider valleys during the afternoon hours on Sunday.
However, subtle changes in the low track could either increase or
decrease snowfall amounts as more rain and warmer temperatures could
work into the region. However, confidence is growing that we will
see 2 to 4 inches of snow in the Champlain and St. Lawrence Valleys
while the Adirondacks and central/eastern Vermont will generally see
3 to 6 inches of snow. Some upslope is expected across the western
slopes of the Green Mountains where summit sites could see 6 to 10
inches of new snow. Thus, we have issued a Winter Weather Advisory
for the Adirondacks and central/eastern Vermont from 8 PM Saturday
through 8 AM Monday.
KEY MESSAGE 2: Following the weekend clipper, strong surface high
pressure is expected to situate across the region. Subsidence from
the building high pressure will help dry out the low to mid levels
leading to a break in the recent active precipitation regime.
However, we will remain under the influence of an upper level trough
with anomalously cool temperatures at the 850 mb and 500 mb levels.
This will help keep temperatures about 5 degrees below seasonal
normals but nothing too atypical for late March.
KEY MESSAGE 3: Temperatures are likely to trend a few degrees below
seasonal average mid week into the weekend as the storm track
remains draped across the Northeast under broad cyclonic 500mb flow.
This pattern favors fast moving waves and clipper-style systems.
Guidance points to above freezing daytime temperatures for area
valleys and overnight lows below freezing - a good cycle for maple
production. Models continue to point to a potentially impactful
system to move through Thursday, but system trajectory will be key.
For now, kept daytime rain and rain/snow chances with overnight snow
showers. The biggest limiting factor for this system will be its
speed at which it moves through, but as we saw yesterday, frontal
character matters - so we will continue to watch evolution in case
strong forcing signatures develop. Another wave will quickly follow
on Friday with additional chances for elevation dependent snowfall.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
Through 18Z Sunday...Patchy stratocumulus is over the area with bases
as low as 1500 ft agl. This will slowly erode as the day progresses.
North to northwest winds of 4-10 knots is common, with KRUT faster
at 14 knots and gusting to 20 knots. These winds will abate and
trend light and variable. The next weather system will approach from
the west around 00z with high clouds initially. Snow will take a few
hours to reach the ground, but reduced visibilities and falling
ceilings will likely begin between 02z-06z. The highest snowfall
rates will be from 06z-14z with visibilities to 3/4SM-2SM and
ceilings falling to 700-1500 ft agl. During the snow, winds will
come out of the southeast to northeast. Some LLWS will be possible
as southwest winds at 2000 ft agl overrun cooler southeast to
northeast winds. Surface wind speeds after 14z will increase to 7 to
15 knots, with the highest at KMSS where northeast winds will
channel through the St. Lawrence River Valley. For KRUT and KBTV,
rain will likely mix in as temperatures warm. Patchy freezing drizzle
will also be possible at KMSS and KSLK from decreasing cloud ice.
Confidence is low to medium, and have noted in a PROB30 from 12z to
18z Saturday.
Outlook...
Sunday Night: MVFR/IFR conditions possible. Chance SN.
Monday: MVFR. Slight chance SN.
Monday Night: Mainly VFR, with local MVFR possible. NO SIG WX.
Tuesday: VFR. NO SIG WX.
Tuesday Night: Mainly VFR, with local MVFR possible. Chance SHSN.
Wednesday: Mainly VFR, with local MVFR possible. Chance SHSN,
Chance SHRA.
Wednesday Night: Mainly VFR, with local MVFR possible. Slight
chance SHSN.
Thursday: MVFR/IFR conditions possible. Chance SHSN, Chance SHRA.
&&
.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 8 PM this evening to 8 AM EDT
Monday for VTZ003-004-006>008-010-017>021.
NY...Winter Weather Advisory from 8 PM this evening to 8 AM EDT
Monday for NYZ027-030-031-034.
&&
$$
WHAT HAS CHANGED...Clay
DISCUSSION...Boyd/Clay
AVIATION...Haynes
EQUIPMENT...NWS BTV
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