878
FXUS61 KBTV 200902
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
402 AM EST Thu Nov 20 2025
.SYNOPSIS...
High pressure will persist for one more day before precipitation
chances return. A trace to a few hundreths of an inch of rain,
and a little high elevation snow, will fall on Friday and
Friday night associated with a modest warm up. Then seasonably
cool late November conditions will resume for the rest of the
weekend, followed by another quick moving system on Monday and a
more widespread precipitation event likely beginning Tuesday
night.
&&
.NEAR TERM /THROUGH FRIDAY/...
As of 401 AM EST Thursday...Per observations of freezing fog in
the St. Lawrence Valley and here at BTV, went ahead to issue a
rare Freezing Fog Advisory (first here in over 10 years), tied
to where very low clouds have been present on satellite imagery.
Dense fog is only patchy based on visibility sensor data, but
within the dense fog, visibilities of 1/4 to 1/2 mile will be
possible, along with icy conditions as condensation freezes with
temperatures only in the middle 20s. The potential for freezing
fog coincides with the morning commute, so please use caution
driving.
Previous Discussion...
Early this morning we are dealing with terrain-driven stratus
and mist as the center of surface high pressure has been
anchored over the western Adirondacks. This pattern has kept us
in subsident flow which keeps these clouds quite shallow and
hard to scour out, and very light flow causes the coverage of
the clouds to change only gradually. Analysis of surface
divergence shows light easterly flow in the St. Lawrence Valley
pushing the cloud bank every so slowly towards the west, whereas
northerly/northwesterly flow in the Champlain Valley has helped
expand these clouds southward and slightly eastward with time.
The center of the ridge should ever so slowly shift towards the
east, helping to shift winds enough to cause cloudy areas to
trend sunny, but confidence in this occurring or predicting the
timing is fairly low given how shallow these clouds are and
light the winds will be to help mix them out. Model guidance
suggests they will erode through the morning hours, with perhaps
the far northern Champlain Valley including northeastern
Clinton County hanging on longest into early afternoon.
Otherwise, quiet weather will continue today into tonight with
mainly some high clouds. More notable increasing cloudiness will
occur after midnight ahead of a frontal system, along with some
modest southerly winds. West-southwesterly winds aloft will
gradually increase through the day tomorrow, probably peaking in the
evening hours. That will be coincident with the passage of a diffuse
surface cold front, such that mountain summit wind gusts could reach
as high as 45 MPH. As stability decreases, the jet will relax
somewhat, limiting peak gusts. Think at greatest roughly 25 to 30
MPH on east facing slopes of hills/mountains, while valleys maintain
a stable surface layer longer to keep winds even lighter. Daytime
southerly flow is a bit more predictable and have boosted favored
areas in northern New York and Champlain Valley into the 20-25 MPH
range; a few higher gusts could occur, but the gradient is not
particularly strong and the aforementioned westerly component to
winds aloft works against stronger winds.
Trends have continued to point towards only spotty light rain
showers, with only an hour or two at best of measurable
precipitation for most locations, and mainly limited to northern
areas closer to the upper level forcing/deeper moisture. Timing
is generally during the daytime hours, but favoring the
afternoon/evening slightly. Ingredients for organized or
substantial precipitation remain lackluster. It does look like
a high probability of at least some rain falling during the day
but with many locations only seeing a trace of rainfall; with hourly
PoP it is hard to show this idea given low predictability of
when a given location will see showers. Precipitation type
could be snow in the highest summits with this event; while
there is some uncertainty in snow levels, generally they will
rise to 3 to 4 thousand feet during the day, and then trend
lower late from west to east, perhaps not until tomorrow night.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
As of 138 AM EST Thursday...Friday night we`ll see any
lingering light precipitation trend towards some light drizzle
as clouds depths decrease. Perhaps there will be some freezing
drizzle in the mountains, and as cooler air returns following a
wind shift to westerly flow, localized icy conditions will
develop where roads became wet on Friday. Otherwise this will be
a pretty quiet period as low pressure system passes south of
Long Island. Note that this weather maker has trended northward,
so we`ll keep an eye on it as far southern areas could be on
the northern fringe of its precipitation shield. Seasonably cold
air on moderate northwest flow will support temperatures back
to below normal with high temperatures mainly in the 30s,
roughly 5-10 degrees below Friday`s highs.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 107 AM EST Thursday...Seasonable end of November weather is
expected Sunday and into the start of next week with subtle ridging
preceding our quick moving system for Monday. Departing troughing
Saturday night will lead to brief zonal to subtle ridging for the
better part of Sunday with a warming trend beginning for the start
of next week. A fast moving clipper system will skirt the northern
portions of the area Sunday night into Monday with chances of
precipitation. The center of the system will track north of the
International Border which will keep most of the precipitation
as rain, however, overnight cooling in the Northeast Kingdom and
in the higher terrain, could lead to some flakes mixing in,
particularly in Essex Co, VT. Additionally, a tightening
pressure gradient will bring some breezy northwest winds during
the day Monday. The system quickly exits by Monday evening with
the upper air flow pattern relaxing as more broad scale ridging
takes over. Temperatures will continue to be slightly above
average for Monday and Tuesday with highs into the upper 30s to
low 40s. Overnight lows will generally be 20-30 degrees with
some radiational cooling potential Monday night if there is any
cloud breaks behind the Monday clipper system. There is
increasing confidence in a larger scale system by mid week with
a deepening low that will move out of the northern Plains and
phase with a lee cyclone moving northeastward from the high
Plains. Widespread precipitation chances looks favorable Tuesday
night through Thursday. While current thermal profiles look to
be primarily rain for the duration of the event, specific
details will continue to become clearer as we get closer.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
Through 06Z Friday...While high pressure is centered overhead, low
stratus has become entrenched in the valley terminals of MSS/PBG/BTV
with freezing fog at SLK. The stratus deck is lowest at MSS with
cigs to 300ft agl, with 500-1000ft agl at PBG/BTV. Satellite shows
the stratus deck firmly in place south to BTV, but thins out further
south at this hour. There is low confidence in any extension to RUT
due to terrain driven sfc winds and less moisture southwards, as the
BTV/PBG stratus is aided by Lake Champlain. Satellite also has
indicated some stratus extensions into Lake Memphremagog which could
propagate south towards EFK by 08Z or so. Have only used a TEMPO
group at EFK due to some moisture profile uncertainties in the near
term. Chances of IFR to even LIFR vsbys are greatest at SLK due to
the presence of vicinity fog, and perhaps at MSS over the next 4 or
so hours based on nearby obs at Ogdensburg and Potsdam. Vsbys at
PBG/BTV should remain VFR under the stratus deck. Model soundings
suggests this stratus decks should persist to at least 14Z when
southerly surface flow should increase enough to scour out the low
level moisture, although it should be noted, model guidance has been
poor resolving this stratus deck altogether. Outside of the stratus
impacted terminals, MPV should continue at VFR until at least 10Z
when persistence fog looks possible. Given last nights similar
conditions, a few hours of fog are possible, so have included a
TEMPO group from 10-14Z based on last nights fog duration. Winds
today will be light and variable through the TAF period.
Outlook...
Friday: Mainly VFR, with areas MVFR possible. Chance RA, Chance
FZRA, Chance SN.
Friday Night: Mainly VFR, with areas MVFR possible. Chance SHRA,
Chance SHSN.
Saturday: Mainly VFR, with areas MVFR possible. NO SIG WX.
Saturday Night: Mainly VFR, with areas MVFR possible. NO SIG WX.
Sunday: Mainly VFR, with local MVFR possible. NO SIG WX.
Sunday Night: MVFR. Chance SHRA, Chance SHSN.
Monday: Mainly VFR, with areas MVFR possible. Chance SHRA, Chance
SHSN.
&&
.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.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Freezing Fog Advisory until 10 AM EST this morning for VTZ001-
002-005-009.
NY...Freezing Fog Advisory until 10 AM EST this morning for
NYZ026>028-035-087.
&&
$$
SYNOPSIS...Kutikoff
NEAR TERM...Kutikoff
SHORT TERM...Kutikoff
LONG TERM...Danzig
AVIATION...Danzig
EQUIPMENT...Team BTV
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