275
FXUS61 KBTV 091821
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
121 PM EST Tue Dec 9 2025
.SYNOPSIS...
After a cold start to the morning, temperatures will quickly rise
today as southerly flow develops. Widespread light snowfall will
move through tomorrow into tomorrow night, with accumulations
generally expected to be in the two to five inch range. The colder
and active pattern will continue into next week with a few
additional chances for snow, though no big snowstorms are expected.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 830 AM EST Tuesday...Just sending out a quick update here
to update hourly temps and dew points. It`s quite cold out
there, and we want to make sure those heading out this morning
are prepared for the frigid temperatures and wind chills. Stay
warm!
Previous discussion...Mostly ideal radiational conditions have
developed tonight, causing temperatures to drop quickly.
Everywhere outside the areas immediately along Lake Champlain
have fallen below 0, with many areas outside the broad valleys
around and below -10. Temperatures will drop a few more degrees
in most places before the night is over. While southerly flow
will begin to develop late in the night, it should not have a
significant effect on impeding the radiational cooling. While
this cold is uncommon for the time of year, it is not
unprecedented. Plattsburgh looks to have broken two record lows
already. It was
-11 right at 1159/1200, breaking the -7 record on 12/08 and the
-10 record on 12/09. The cold temperatures and relatively light
winds have allowed a lake cloud to develop on the mostly
unfrozen Lake Champlain. It has formed over the southern waters
and it will gradually expand northward as the night goes on. It
may move into areas adjacent to the lake in the early morning.
Increased southerly flow and associated mixing/drying, along
with warming temperatures, should cause it to dissipate during
the day. An area of warm air advection aloft will move through
this evening and cause a period of light snow. Very dry low
levels will likely cause a lot of it to evaporate before it
reaches the ground, but there should still be some very light
snow.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
As of 137 AM EST Tuesday...A quick moving storm system moves through
Wednesday and Wednesday night, tracking up the St. Lawrence Valley.
Warm air advection should cause a quick period of moderate to heavy
snow on the front end. Here, snowfall rates could briefly reach
around an inch per hour. The snow will become lighter for the rest
of the day and into the night, and a dry slot moves in for the
evening. Strong southwesterly winds will cause downsloping and
mostly end the precipitation in the Champlain and Connecticut
valleys in the afternoon. Gusts in the 25 to 35 mph range are
possible in the Champlain Valley as enough of a southerly component
and an inversion below ridgetops should allow for efficient
channeling. Temperatures will rise slightly above freezing in the
broad valleys, but steep lapse rates should mostly keep the
precipitation snow. As the center of the low passes to the east,
northwest flow develops and it should cause a brief period of
upslope snow Wednesday night. Overall, totals in the two to five
inch range are generally expected. The lake effect band should stay
to the south of our northern New York zones, though the moisture
will still enhance totals in the central and southern Greens. Drier
conditions should prevail during the day Thursday, but moisture
looks to back down from the north and reinvigorate the upslope snow
in the evening.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
As of 137 AM EST Tuesday...Primary highlights for the long term
include upslope snow showers on Thurs night into Friday, another
light snow event on the weekend, followed by another very cold
airmass late Sunday into early next week. First item wl be a classic
upslope fluff event on Thurs night into Friday, as progged 850mb
temps fall btwn -12F and -20F with lingering 925mb to 500mb rh >70%.
Latest GFS/ECMWF show the closed 700/500mb circulation becoming
vertically stacked just north of the International Border, which
should promote favorable 925mb to 850mb winds of 25 to 40 knots,
resulting in additional upslope accumulating snowfall thru Thurs
night. Have bumped pops into the high likely range for Thurs night
with additional accumulations of 2 to 4 inches of fluff, but
localized 4 to 6 inches possible from Mansfield to Jay Peak. We will
continue to monitor depth of moisture to fine tune snowfall amounts,
but moderately strong caa should help squeeze out remaining moisture
in the mtns. Next fast moving clipper like system associated with
positively tilted mid/upper lvl trof arrives late Sat into Sun. Did
note the 00z ECMWF is a bit more aggressive with sharpening trof and
develops a slightly stronger area of sfc low pres along the mid
Atlantic into southern New England. The GFS/UKMET and CMC show more
of a clipper like system with a period of light snow late Sat into
Sunday, followed by another very cold airmass late Sunday into early
next week. This airmass looks to be associated with bitterly cold
wind chill values as progged 850mb temps drop btwn -22F and -25F
with gusty northwest winds. Cold headlines are likely needed for
Sunday night into Monday. This wl be an advection type of cold on
Sunday night, followed by radiational cooling on Monday night into
Tues with building sfc high pres. Given latest trends additional
lowering of temps is likely on Sunday through Tuesday of next week,
where highs may struggle to reach 10F in many spots on Monday, with
values well below zero again on both Sunday and Monday nights. Cold
air wl help to squeeze out a few upslope snow showers on Sunday into
Sunday night, before column becomes too dry.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
Through 18Z Wednesday...It is a quiet forecast over the next six
hours with a layer of altostratus present ahead of a warm front,
then active conditions including LLWS and snow will follow. Bulk of
steady snow will be between 12Z and 18Z, with visibilities likely
as low as 1/2SM at most sites towards the end of the period.
Character of snow initially will be dry and very light with the
first showers that arrive in the 00Z-12Z period. In fact, at PBG and
BTV, precipitation may be virga with little or no operational
impact. Widespread snow then arrives towards 12Z and become
much heavier, trending wet, especially at KRUT where snow to
liquid ratios could be near 10:1. Other sites will see snowfall
with mainly moderate snow to liquid ratios closer to 12:1.
Flight conditions will be driven by visibilities, as ceilings
lower to mainly 2 to 5 thousand feet outside of the steady snow.
Southwesterly winds aloft will greatly increase tonight,
leading to LLWS as surface winds remain southerly and relatively
light (around 10 knots). Greatest risk of LLWS is at RUT, MPV,
and SLK and during the predawn hours. After a lull, LLWS will
return towards the end of the TAF period. Other sites will tend
to see turbulence but less shear, with wind gusts as high as 25
knots at BTV, especially prior to 12Z and arrival of snow.
Outlook...
Wednesday Night: MVFR/IFR conditions possible. Chance SHSN.
Thursday: Mainly VFR, with local MVFR possible. Chance SHSN.
Thursday Night: VFR. Slight chance SN.
Friday: VFR. NO SIG WX.
Friday Night: Mainly VFR, with local MVFR possible. Slight chance
SN.
Saturday: Mainly VFR, with local MVFR possible. Chance SN.
Saturday Night: Mainly MVFR, with local IFR possible. Chance SN.
Sunday: Mainly VFR, with local IFR possible. Chance SN.
&&
.EQUIPMENT...
NOAA Weather Radio station WXM-44, transmitting from Mt.
Ascutney, Vermont, on frequency 162.475 MHz is non-operational
at this time. NWS technicians have diagnosed the problem, but
repairs will likely not be able to occur for quite some time due
to circumstances beyond our control. Therefore, the time of
return to service is currently unknown. The following NOAA
Weather Radio transmitters may be able to provide service during
this outage: WWG 50 from Burke Mtn, VT at 162.425 MHz and WNG
546 from Hanover, NH at 162.525 MHz.
Equipment malfunctions at the Colchester Reef meteorological
station will likely leave it inoperable for an extended period
of time. This site is not serviced by the NWS. Technicians do
not currently have an estimated return to service for this
station. Use extra caution when navigating the broad waters of
Lake Champlain, and please contact us if you observe winds
significantly deviating from the forecast.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Winter Weather Advisory from 7 AM Wednesday to 1 AM EST
Thursday for VTZ004-006>008-010-011-017>020.
NY...Winter Weather Advisory from 7 AM Wednesday to 7 AM EST
Thursday for NYZ026-027-029-030-034-087.
&&
$$
SYNOPSIS...Myskowski
NEAR TERM...Myskowski/Storm
SHORT TERM...Myskowski
LONG TERM...Taber
AVIATION...Kutikoff
EQUIPMENT...Team BTV
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