Area Forecast Discussion
Issued by NWS Burlington, VT

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS61 KBTV 282350

Area Forecast Discussion
National Weather Service Burlington VT
650 PM EST Tue Nov 28 2023

Scattered snow showers and gusty winds will diminish tonight as
a weak cold front exits the region. Aside from some lake-
effect snow showers in the St. Lawrence Valley on Wednesday,
mainly dry conditions are expected until Friday when chances of
widespread light rain and snow increase. A more substantial
weather system is possible early next week.


As of 557 PM EST Tuesday...Snow showers continue across much of
Vermont as well as the Champlain Valley of New York. The rest
of our northern NY counties have more isolated to no showers as
of 6 PM and we are expecting quiet conditions to continue there.
We are also anticipating showers elsewhere to gradually taper
off over the next few hours, bringing dry weather to the entire
forecast area by the late night hours. However, it`s not out of
the question for some light lake effect showers to trickle into
St. Lawrence County from Lake Ontario, though with projected
winds, the lake effect band will progress southward, away from
our forecast area, at least tonight. There could also be a few
lingering showers in the Northeast Kingdom. Lake effect snow
could return to St. Lawrence County tomorrow. One other small
adjustment made with this update was to increase dew points,
which were a bit under observations in the teens. Previous
discussion below:

Previous discussion...Main impactful weather is occurring early
in the period with otherwise largely cold and quiet weather
expected. Scattered snow showers will continue through early
evening while gradually shifting south and east of the region as
a weak surface cold front passes through. It`s been an
interesting afternoon meteorologically as we have a lot of
ingredients for snow squalls except for a strong front; dry road
temperatures are near or above freezing, instability is high
for a winter event with CAPE values in the 75 to locally 150
J/kg range, and deep mixing is occurring with inverted V
soundings showing momentum transport supportive of gusts upwards
of 30 MPH. An SPS was issued to bring attention to potential
impacts to travel; however, since snow intensity is largely
unimpressive due to poor surface convergence, the coverage of
squall-like snow will be rather isolated, found in only the most
intense cells.

Abundant dry air aloft and highly unblocked flow tonight will
limit snow accumulations overnight, with up to a few inches in
the mountains and mainly a coating or less elsewhere.
Temperatures should settle down into the teens to locally single
digits as the core of the post-frontal cold air slides overhead
by daybreak featuring 850 millibar temperatures as low as 17
below zero Celsius, or just above zero Fahrenheit a few thousand
feet above ground. Southwesterly flow will develop during the
day and a lake response is expected off of Lake Ontario with
ample instability. The resulting snow band will lift into St.
Lawrence County and weaken with time, but light snow
accumulation of 1 to 3 inches in western and southern portions
of the county are expected tomorrow night. Highest probabilities
of steadier snow appears to be during the nighttime hours as
low level southwest flow intensifies transporting better
moisture through the valley. Temperatures across northern New
York into Vermont will stay near or below freezing tomorrow,
although expect somewhat less cold readings (nearly 10 degrees
milder) tomorrow night given continued moderation of the air
mass on south to southwest winds.


As of 346 PM EST Tuesday...Any lingering Lake effect showers in
St. Lawrence County will end quickly on Thursday as increased
temperatures and wind shear make conditions for lake effect
precipitation unfavorable. Southwest flow will help with warm
advection so temperatures should rise to the upper 30s and 40s
during the day Thursday, remaining warmer than seasonal averages
overnight, and warming further, upper 30s to mid 40s for
Friday. There should be a little sun as well. Winds will be a
bit gusty overnight with a southwesterly low level jet moving
over the region. Winds should be enhanced over the route 11
corridor a little, but a weak inversion should prevent some of
the higher winds from mixing down. A cold front moves into the
region on Friday but it will be weakening so it should only
bring a few showers at first. A weak low will ride along it late
Friday into Friday night, with the center looking to pass just
off the New England coast. There is pretty high confidence with
relatively low precipitation amounts with QPF totals likely
being a half inch or lower. There looks to be a sharp
precipitation gradient somewhere over the North Country. The GFS
is continuing to bring precipitation all the way to the
international border while the Euro has it only reach southern
areas; opted for a blended approach keeping lighter amounts
towards the international border and more modest amounts for
central and southern Vermont. The storm looks to be mostly rain
in the valleys and snow at higher elevations with the highest
snowfall totals currently looking to be in the Southern Greens
with up to 4" possible and favoring amounts more in the 1-3 inch


As of 346 PM EST Tuesday...The main event in this period will
be a potentially more impactful storm system. There is still
high uncertainty of the details and timing of the storm with the
EPS favoring heavier precipitation and more snow while the GEFS
favors lighter precipitation and more rain. However, many of
the GEFS members have a stronger low with more snow toward mid
week. As such, model consensus is that there will be a period of
precipitation, but whether or not it will be on the colder side
remains questionable.

Models depict a longwave trough digging down over the middle
part of the country over the weekend and a shortwave will rotate
along it as the longwave moves east. Best guidance places the
shortwave passing through the region Sunday night into Monday.
All the models generally attempt to form a low off the New
England coast during this time period, but its strength and
track are very uncertain. The Euro strengthens the storm the
most and the ensemble members are somewhat agreement, with the
EPS probability of 6 or more inches of snow being over 50
percent. However, the GEFS probabilities are less than 10
percent for the Sunday night storm. When the time period
increased until Wednesday to take into account the timing
differences and possible subsequent storm, the EURO
probabilities rise to 70-80 percent of seeing 6 or more inches
while the GEFS probabilities rise to about 30 percent. In
summary, there is the possibility for impactful snow Sunday
night into Monday, but will be tied closely to storm track and
whether or not moisture/cold air remains over the North Country.


Through 00Z Thursday...Scattered snow showers continues across
our region, but will be dying down overnight. Currently IFR
conditions are present at EFK, MPV and SLK with light snow and
visibility around 2SM. Winds continue to be gusty out of the
northwest, but also will be dying down overnight. Lower ceilings
may linger, keeping SLK/MPV/EFK IFR or MVFR. Conditions should
improve to VFR at all sites by about 06z, and winds become
light. Winds pick up out of the south southwest after 12z.


Wednesday Night: Mainly VFR, with local MVFR possible. Slight
chance SHSN.
Thursday: VFR. NO SIG WX.
Thursday Night: Mainly VFR, with local MVFR possible. Chance
Friday: Mainly MVFR, with areas VFR possible. Chance SHRA.
Friday Night: Mainly MVFR, with areas IFR possible. Chance SHRA,
Chance SHSN.
Saturday: MVFR/IFR conditions possible. NO SIG WX.
Saturday Night: VFR. Slight chance SHSN.
Sunday: Mainly MVFR, with local IFR possible. Chance SHRA, Chance




NEAR TERM...Kutikoff/Storm
SHORT TERM...Myskowski
LONG TERM...Myskowski
AVIATION...Neiles is the U.S. government's official web portal to all federal, state and local government web resources and services.