785
FXUS61 KBTV 182353
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
753 PM EDT Sat Apr 18 2026
.WHAT HAS CHANGED...
As of 321 PM EDT Saturday...
Potential for snowfall into lower elevations has increased for
Sunday. Additional snow showers also are expected on Monday with
unseasonably cold air and trough moving through.
&&
.KEY MESSAGES...
As of 321 PM EDT Saturday...
1. Gusty winds will continue ahead of an approaching cold
front, with the strongest gusts across northern New York and near
the International Border this evening.
2. Widespread rain will change to snow before ending during the
day on Sunday. Minor snow accumulations and slushy, slippery travel
is possible during the day.
3. Unseasonably cold conditions Sunday night into Monday night
will be accompanied by a chance of snow showers, especially Monday
morning.
4. Temperatures are favored to warm back to seasonal averages
through the week with some potential for showers late next week.
&&
.DISCUSSION...
As of 321 PM EDT Saturday...
KEY MESSAGE 1: A Wind Advisory remains in effect for Franklin and
Clinton Counties in northern New York from 5 PM today to midnight
tonight for wind gusts between 40 to 50 MPH. The strongest gusts
will primarily be along the US Route 11 corridor from Moira, NY to
Ellenburg Depot, New York, generally from 6 to 9 PM tonight.
A few power outages and downed tree limbs may result.
This afternoon we have seen breezy south to southeast winds across
the region, with gusts mostly in the 30 to 40 MPH range. The
gustiness, associated with sunshine and warm dry air near the
ground, is resulting in steep low level lapse rates. Those lapse
rates support mixing of modestly strong winds aloft and further
drying us out, as relative humidities locally have fallen as low as
30-40% but mainly 40-60%. With low level winds ramping up tonight
and continued dry air mass present, the mixing will tap into more
significant winds aloft. 925 millibar winds of 45 to 55 knots
continue to be modeled across the northern fringes of the
Adirondacks, particularly along US Route 11 such as in Malone, NY.
Enhancement from downsloping will lead to gusts up to 40 to 50 MPH
with a localized gust to 55 MPH possible. The southerly flow also
will lead to channeled winds in the Champlain Valley, which appear
to be localized once again to the western side of the lake due to a
slight easterly component to the near surface flow. The magnitude of
the low level jet does not look concerningly strong, so potential
for downed tree limbs may be enhanced more due to recent wet weather
than due to the winds alone.
KEY MESSAGE 2: A large, highly amplified longwave trough is supporting
a large area of precipitation along a cold fronts steadily
approaching from the west tonight. A strong thermal gradient
will be present and likely increasing with time as the front
moves into our region. The upper level jet configuration, with
jet streaks to our north and south by midday Sunday, will be
favorable for widespread precipitation behind the surface front.
As such, confidence in a (very) late season snowfall is
increasing. Precipitation rates may be heavy enough even for
localized 1" per hour snowfall at times, with moderate snowfall
intensity (>0.05" of liquid in an hour) likely during the
daytime hours from the Adirondacks and points eastward. The
strongest frontogenesis and the more intense precipitation rates
should largely slide eastward such that Advisory level snowfall
amounts are unlikely, but Probability Matched Mean HREF
accumulations are currently in the 1 to 4 inch range for much of
Vermont and northern New York above about 500 feet elevation.
Have nudged temperatures closer to some of the raw model
guidance away from the National Blend to get snow and
accumulations more consistent with the expected cold air
spilling into the region during the day after the cold front
passes through. Given initially marginally cold temperatures, a
wet snow can be expected. However, snow ratios should trend
towards a more average snow density with time; impressively cold
cloud temperatures in the snow growth zone within 10,000 feet
of the surface are expected before snow tapers off.
KEY MESSAGE 3: Main focus for early in the week will be the
unusual cold. While we typically have a final wintry period
before the warm season truly gets underway, Monday does look
potentially within daily record territory, especially for low
temperatures Monday night as high pressure builds in. These
temperatures currently are forecast in the range of 15 to 25,
but clear skies and light winds could support a frigid night, with
temperatures more typical of winter in the single digits to low
teens.
Before skies trend clear, a couple of boundaries will move
across the area Sunday night through Monday to support snow
shower chances. Of most note, the snow squall parameter shows
some favorable ingredients for a minor, scattered type of event
for Monday morning as a secondary cold front/wind shift boundary
moves southward across our region. There will be some
instability, lingering low level moisture, and convergence along
this front to support at least some shower activity. For now
have just a coating of snow indicated over a large area and have
increased the chances of precipitation a bit, as the forcing
looks fairly consistent amongst model guidance. Will add detail
as confidence grows, but overall not looking like a significant
event other than the fact that it is late in the season for
winter weather.
KEY MESSAGE 4: Long wave ridging is expected to displace troughing
through next week, shunting the polar front jet and main storm track
northeastward into eastern Canada. This pattern favors slowly
warming temperatures despite a continued northwest flow pattern.
Highs are projected to warm from low/mid 50s midweek into the 60s
heading into the weekend while lows correspondingly warm from the
30s into the 40s. Models diverge late next week, but the consensus
shows an amplification to the ridge axis which may allow for a
backdoor cold front to drop through the region promoting some shower
chances by Friday night.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
Through 00Z Monday...Gusty S/SE winds and LLWS will be the
primary concern for the first 4-6 hours of the TAF period,
followed by deteriorating conditions in widespread rain changing
to snow associated with a cold frontal passage. Gusts of 25 to
35 kt will persist through the evening hours and the first part
of overnight. Meanwhile, a S/SW 50+ kt jet will bring LLWS and
turbulence through 06z, as well. VFR conditions early in the
period will rapidly drop as ceilings lower overnight, first to
MVFR and then IFR, generally from 06z onward. Ceilings may
briefly lift back to MVFR with the frontal passage, but should
drop again to IFR for at least a brief time 12z-18z as winds
turn to the west behind the front. Widespread rain overnight
into early Sunday will keep visibility 4-6SM, but expect a
gradual changeover to snow after 12z Sun, especially at the
higher elevations. KMPV/KSLK/KEFK most likely to see snow, along
with IFR visibilities. Steady precipitation ends from west to
east after 18z with gradually improving conditions, first to
MVFR and eventually VFR very late in the day.
Outlook...
Sunday Night: VFR. Slight chance SHSN.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. NO SIG WX.
Tuesday Night: VFR. Slight chance SHRA, Slight chance SHSN.
Wednesday: Mainly MVFR, with local IFR possible. Slight chance
SHRA.
Wednesday Night: Mainly VFR, with local MVFR possible. NO SIG WX.
Thursday: Mainly VFR, with local MVFR possible. NO SIG WX.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...Wind Advisory until midnight EDT tonight for NYZ027-028-030-
031.
&&
$$
WHAT HAS CHANGED...Kutikoff
DISCUSSION...Boyd/Kutikoff
AVIATION...Hastings
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