550
FXUS61 KBTV 150722
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
322 AM EDT Sun Mar 15 2026
.WHAT HAS CHANGED...
As of 259 AM EDT Sunday...
A High Wind Warning for portions of northern NY and a Wind
Advisory for St. Lawrence County and the northern Champlain
Valley has been issued from 11 PM Sunday until 8 PM Monday.
&&
.KEY MESSAGES...
As of 259 AM EDT Sunday...
1. A wide spectrum of weather hazards are expected through
Tuesday.
2. High Wind Warning and Wind Advisories for portions of
northern New York and the northern Champlain Valley. Strong
south winds could produce isolated to scattered power outages.
3. Brief abnormal cold behind the early week front will be
followed by seasonable weather conditions with a few chances for
showers.
&&
.DISCUSSION...
As of 259 AM EDT Sunday...
KEY MESSAGE 1: A strong 1034mb surface high will shift eastwards over
the course of the day. The relatively clear and calm conditions even
managed to produce a little freezing fog near Massena. Increasing
cloud cover is expected today, as a warm front will nose
northwards once high pressure moves offshore. This will bring a
period of light snow, mainly over northern New York this
afternoon before quickly skirting north. The combination of dry
air and weak forcing will result in minimal accumulations.
Behind the warm front, winds will begin to accelerate. Winds are
expected to be the most significant hazard for this event, but
will give the winds their own segment. These south wind gusts
will presage a strong cold front. Ahead of that front, a
moisture plume off the Atlantic will lift north pre-dawn Monday
into the early afternoon. Most of the moisture is confined to
the lower levels. The focus will mainly be along the Vermont-New
Hampshire border before pivoting back to the east. Temperatures
in cold hollows of eastern Vermont will still likely be about
30 degrees, and so localized patchy freezing rain or drizzle is
possible. Aloft, the strong inversion overhead will result in
some elevated instability. Some high res guidance is evening
suggesting some thunder is possible in the St. Lawrence Valley
early Monday morning if some convection can fire. The period of
freezing rain/drizzle will be short-lived, as the strong
southerly flow will push temperatures above freezing around
sunrise. Given the localized, conditional nature of the freezing
drizzle, no Winter Weather Advisories have been posted for
this.
South flow will warm temperatures well into the mid 50s to mid 60s
across the region. The combination of increasing temperatures,
winds, and dewpoints will start to eat away snow. However, most
of the forecast area below 1500 foot elevation has lost its
snowpack, and any snow from yesterday doesn`t have too much
liquid in it. Additionally, the frontal boundary to arrive on
Monday evening will be fast moving with cold air quickly filling
in to the east. Unlike before, this stint of warm weather isn`t
going to be prolonged. Liquid amounts for Monday and Monday
night are about 0.40-1.00", and some of this will be in the form
of snow on the backside of the front. We`ll likely see river
rises, but it doesn`t appear likely that hydro will be a
significant concern.
The dynamics of a strong upper jet streak and vort max behind
the front, along with the strength of cold air advecting
immediately after the cold front, will change precipitation over
to snow. This will be most pronounced over northern New York,
where 1-5" will be possible. Sections of western Vermont may
approach 1", and then better dynamics lift north before snow
gets into eastern Vermont. Temperatures may cool 20-30 degrees
in 3-4 hours, but if temperatures are in the mid 50s-mid 60s,
this means we may not quite get below freezing to meet flash
freeze criteria. Winds may also help dry surfaces before black
ice can form. Still, we`ll monitor this potential as well with
precipitation tapering off Tuesday morning.
KEY MESSAGE 2: Upgraded the High Wind Watch to a High Wind
Warning, and expanded Wind Advisories along the periphery into
St. Lawrence County and the northern Champlain Valleys. Strong
pressure gradients will develop as 1030-1033mb surface high
pressure remains in the Canadian Maritimes while a 985-988mb
surface low moves up the Great Lakes. The strongest winds gusts
up to 60 mph will be along the Route 11 corridor across northern
slopes of the Adirondacks between 2AM and Noon Monday.
The incoming low-level jet will lift northwards behind today`s
warm front. Initially, stable conditions may limit the ability
for winds to move downslope. However, once the warm front
properly clears the region later tonight and surface
temperatures begin increasing, we will see winds quickly ramp
up. The intensity of the low-level jet seems to be settling
towards 65-75 kts, with embedded areas around 80 knots. Although
the inversion layer is fairly low to the ground, winds just
under 1000 feet will be about 60 knots already. So it will not
take much mixing to filter strong winds to the surface. The
period of gusts will be somewhat prolonged, with a nearly 6-10
hour span of 50-60 mph gusts along Route 11 in New York. So
power outages and down trees could occur.
Over the St. Lawrence Valley and the Champlain Valley, the
strength of gusts will likely range more in the 40-50 mph range,
perhaps locally to 55 on northwest slopes of the northern
Greens. Stronger stability could limit how far downslope winds
get down the valley. In spite of this, it appears winds around
1000 ft aloft are still about 55-60 knots out of the south to
southeast. The southeasterly direction is more favorable for
downslope gusts, and a little less favorable for channeled flow
in the northern Champlain Valley. Winds will shift out of the
south at some point, and the strong warming should allow mixing
to reach the surface later in the day.
For south-central and eastern Vermont, there`s somewhat greater
uncertainty due to how long the plume of Atlantic moisture
lingers before shifting east. The smaller window for drying and
southeasterly winds producing even stronger stability will
likely limit mixing until winds trend south-southwesterly just
ahead of the front. So whether strong gusts in these areas are
currently in the 30-40 mph range.
KEY MESSAGE 3: Strong caa will follow close behind the strong cold
front early this week. Temperatures will struggle to warm during the
day Tuesday with our high temperatures occurring early Tuesday as
temperatures fall throughout the day. Temperatures will bottom out
Tuesday night in the single digits east of the Greens, the low teens
in the Champlain Valley, and low to mid single digits across
northern New York. The colder hollows of the Adirondacks may even
flirt with zero degrees. The strong caa will be aided by a lingering
850mb jet to 50kts, with a well mixed boundary layer. Surface gusts
during the morning and afternoon on Tuesday could gust up to 30-40
MPH, with the strongest winds across the northern St. Lawrence
Valley. Apparent temperatures subsequently on Tuesday will be in the
single digits for most locations, with some below zero apparent
temperatures Tuesday night across northern New York. Temperatures
will slowly rebound Wednesday and into the latter half of next week
with highs returning to seasonable levels in the upper 30s to low to
mid 40s by the end of next week.
Precipitation chances will be hard to come by for most of next week,
with the best chances immediately following the cold front earlier
in the week. Behind the strong cold front Monday Night, southwest
winds with lingering instability to 60-110 J/kg should be enough to
sustain some light lake effect snow during the day Tuesday across
southern St. Lawrence County and the western Adirondacks in New
York. The temperature difference across the lake and air will not be
large enough for significant snow amounts, with the forecast
favoring only an inch or two in the aforementioned areas. Winds will
shift more westerly by Tuesday evening shifting the band south of
the region, but as it does so, a dusting downstream in the central
Greens cannot be ruled out. High pressure will build in for mid week
and give us a few generally dry couple of days, but shower chances
increase as a couple shortwaves traverse the area under nearly zonal
flow aloft. There`s still some uncertainty with these as they
do appear rather weak, but better chances appear more likely by
the end of next week. Temperatures would support some mountain
snow with any shower chances next week, with more rain/snow in
the valley with boundary layer temperatures in the mid to upper
30s.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
Through 06Z Monday...Conditions will continue to remain VFR through
the TAF period, outside of EFK in the immediate near term due to
some lingering light snow showers. EFK showers should taper off by
08Z. Otherwise, ceilings will remain generally above 5000ft agl
today for all sites with winds areawide trending towards calm ahead
of a weak warm front this afternoon. As the warm front pushes from
south to north around 18Z, mainly only MSS/SLK should see any
precipitation in the form of snow, with MSS seeing a chance at
potentially some brief reductions in visibility to MVFR for a few
hours. Have only used a PROB30 at MSS for this package with PoPs
35-50%. Behind the warm front, winds will become southeasterly and
rapidly increase with gusts by 00Z rising to 15-20kts, and 30-40kts
by 06Z. LLWS will be a concern after 00Z Monday with a LLJ of
65-75kts, leading to LLWS at 2000ft between 50-70kts, strongest at
SLK/PBG/EFK.
Outlook...
Monday: MVFR/IFR conditions possible. Windy with gusts to 35 kt.
Likely RA, Chance SHRA.
Monday Night: MVFR/IFR conditions possible. Windy with gusts to
35 kt. Definite RA, Likely SN.
Tuesday: VFR. Windy with gusts to 35 kt. Slight chance SHSN.
Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. NO SIG WX.
Wednesday Night: VFR. Slight chance SN.
Thursday: Mainly VFR, with local MVFR possible. Slight chance RA,
Slight chance SN.
&&
.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...Wind Advisory from 11 PM this evening to 8 PM EDT Monday for
VTZ001-002-005-016>018.
NY...Wind Advisory from 11 PM this evening to 8 PM EDT Monday for
NYZ026-028-029-035-087.
High Wind Warning from 11 PM this evening to 8 PM EDT Monday
for NYZ027-030-031-034.
&&
$$
WHAT HAS CHANGED...Haynes
DISCUSSION...Danzig/Haynes
AVIATION...Danzig
EQUIPMENT...NWS BTV
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