274
FXUS61 KBTV 021133
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
733 AM EDT Thu Apr 2 2026
.WHAT HAS CHANGED...
As of 346 AM EDT Thursday...
A Winter Weather Advisory is now in effect for areas along and
east of the Green Mountains, particularly above 1000 feet
elevation, where a minor ice event is expected tonight.
&&
.KEY MESSAGES...
As of 346 AM EDT Thursday...
1. Light wintry precipitation and light icing are likely in the
mountains and much of Vermont east of the Green Mountains,
mainly during the nighttime hours. Slick travel conditions are
possible which could impact the Friday morning commute.
2. Unseasonably warm conditions expected Friday and again
Saturday night into Sunday, with showers and gusty winds but no
significant impacts.
3. Light snow showers expected Monday into Tuesday as upper
trough crosses the north country. Cooler than normal
temperatures are expected through Wednesday night.
&&
.DISCUSSION...
As of 346 AM EDT Thursday...
KEY MESSAGE 1: A mid-level wave riding along a persistent front
to our south is producing light rain early this morning in
southern Vermont. With messy thermal profiles near the ground,
some sleet and snow may mix in with the rain but no impacts are
expected given the very light intensity and sub-freezing
temperatures only in the mountains through this period. Once
this wave exits, there will still be a lot of low level moisture
around and terrain driven, easterly upslope type of very light
rain will be possible primarily in southern portions of the
Adirondacks and Greens, but overall things look quiet during
most of the day.
A polar high pressure area to our north will settle into the
Canadian maritimes through the day, promoting an increasing
southeasterly flow with colder air damming up against the Green
Mountains. As a result, as light precipitation spreads
northeastward this evening, we`ll see a minor freezing rain
event develop in portions of central and eastern Vermont. The
degree of cold air will be fairly marginal such that it`ll take
time for temperatures to fall below freezing and this sub-
freezing air will tend to settle in the mid-slopes. Lower
elevations, such as in the Upper Valley and in the vicinity of
Lake Memphremagog, will likely stay just above freezing tonight.
All together, it`s a challenging forecast for ice amounts even
without factoring in the orientation and strength of the
frontogenesis that will focus the bulk of the rain. The
consensus in model guidance is for the steadier rain to spread
into northern portions of the area tonight with precipitation
more showery and lighter in southern areas. So the PoPs are
relatively low in southern portions of the Winter Weather
Advisory area but the flow pattern favors sub-freezing
temperatures more to the south than northern portions of
Vermont. There also is uncertainty in the exact timing of the
steadier precipitation, ranging up to several hours but
generally falling within the nighttime period.
There are a couple of competing factors for ice accumulation.
Wet-bulb temperatures will likely be only as low as 31 degrees
for most of the event, suggesting ice to liquid ratios will tend
to be on the low side. However, winds will be fairly strong,
especially after midnight as a low level jet ramps up, which
helps water freeze more quickly. Would expect as a result some
highly variable ice accumulations, and unfortunately a lot of
these locations will not have a lot of ground truth unless
members of the public measure ice early Friday morning.
Temperatures will tend to warm fairly quickly compared to many
of these types of events as low level flow trends due southerly,
so while the Winter Weather Advisory extends beyond the morning
commute, expect many areas that see freezing rain could have
temperatures rise well above freezing by mid-morning.
KEY MESSAGE 2: Friday looks rather windy, although shy of Wind
Advisory criteria. In particular, southerly/southwesterly valley
channeling and 50-55 knot 925 millibar winds supports peak
gusts above 40 MPH at times in the northern Champlain and St.
Lawrence Valleys. It appears cloud cover and showers will be
prevalent enough to keep temperatures from being particularly
extreme, but it will be quite the turnaround from the recent
cool conditions with highs largely in the 60s.
Cooler and drier northwesterly winds will filter in for
Saturday, which has trended cooler but pleasant with high
pressure briefly building in. The next storm quickly will follow
as the next low pressure system again tracks to our west. A
narrow plume of deep moisture riding out ahead of cold front
will ensure widespread rainfall that could be briefly heavy,
although the potential for significant rain still looks low with
90th percentile 24 hour rainfall amounts per the National Blend
only as high as 1.33" at this time. These higher end amounts
actually only between 0.6" and 1.0" in most of southern and
eastern Vermont where risk of heavy rain is lowest. The
combination of this widespread rainfall and additional higher
elevation snowmelt continues to bring the expectation of sharp
river rises with low risk of reaching bankful.
Winds currently look slightly less impressive compared to
Friday, but overall similar within the St. Lawrence Valley in
particular. This area is favored for a period of stronger
southwesterly winds on Sunday after the cold front passes. More
widespread windy conditions will tend to be muted, as the
primary period of stronger winds aloft elsewhere still looks
aligned with the rain and with a southwesterly orientation that
doesn`t result in much downsloping or mixing potential.
KEY MESSAGE 3: An upper level trough along with several lobes
of embedded shortwave energy will bring upslope snow showers to
our area from Sunday night through Tuesday. Cold air will sink
down over the north country from Canada during this timeframe,
and cooler than normal temperatures will remain through
Wednesday night. Trough pushes east of our area on Tuesday night
into Wednesday bringing upslope showers to an end and a return
to more seasonable temperatures.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
Through 12Z Friday...MVFR conditions only remain at MPV because
of lower ceilings. After 15Z, increased moisture across the
region will likely lead to another period of MVFR ceilings
through the daylight hours, along with increased chances for
precipitation late in the day, generally after 20z. Light and
variable winds this morning, then increase again out of the S/SE
during the daytime. The exception will be KMSS which will hold
onto a NE wind through the period. Winds will become strong and
gusty on Friday.
Outlook...
Friday: Mainly VFR, with areas MVFR possible. Windy with gusts to
35 kt. Chance SHRA, Slight chance TSRA.
Friday Night: MVFR. Slight chance SHRA.
Saturday: Mainly VFR, with local MVFR possible. Chance SHRA.
Saturday Night: Mainly MVFR, with areas VFR possible. Windy with
gusts to 30 kt. Definite SHRA.
Sunday: Mainly MVFR, with local IFR possible. Definite SHRA.
Sunday Night: Mainly VFR, with areas MVFR possible. Slight chance
SHRA, Slight chance SHSN.
Monday: Mainly VFR, with areas MVFR possible. Slight chance SHSN.
&&
.EQUIPMENT...
The Colchester Reef meteorological station is out of service.
This site is not serviced by the NWS. An estimated return to
service is May 1st. Please contact us if you observe winds
significantly deviating from the recreational forecast.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Winter Weather Advisory from 7 PM this evening to 10 AM EDT
Friday for VTZ003-004-006>008-010-018>021.
NY...None.
&&
$$
WHAT HAS CHANGED...Kutikoff
DISCUSSION...Kutikoff/Neiles
AVIATION...Neiles
EQUIPMENT...NWS BTV
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