169
FXUS61 KBTV 282338
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
738 PM EDT Tue Oct 28 2025
.SYNOPSIS...
High pressure will continue to provide the area with mostly clear
skies this evening with patchy fog and freezing fog developing after
midnight and prevailing into Wednesday morning. Lows will be in the
lower 20s sheltered valleys to near 40 near Lake Champlain. Fog and
low clouds will give away to mostly sunny skies on Wednesday, before
clouds and rain showers arrive on Thursday and continue into Friday.
A widespread wetting rainfall is expected with amounts in the 1 to 2
inch range by Saturday.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 228 PM EDT Tuesday...Sfc analysis places 1036mb high pres
southeast of Hudson Bay with light northerly flow prevailing acrs
our fa under mostly sunny skies. Fcst challenge tonight wl be areal
coverage of fog/freezing fog, along with how far temps wl fall.
Dwpts crntly in the l/m 30s with light winds and clear skies, feel
cross over values wl be achieved in many areas, setting the stage
for widespread fog/freezing fog, including parts of the CPV and SLV.
This general idea is supported by the NAM 3KM sounding data and some
support from the HRRR, with sharpening llvl inversion and shallow bl
saturation. Given the light flow, limited mixing, and lower late Oct
sun angle, feel fog/stratus could take until late morning/early aftn
to burn off in several locations. Once skies clear some upper lvl
clouds expand northward during the aftn hours with highs once again
in the 50s.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 228 PM EDT Tuesday...Highly amplified pattern evolves with deep
full latitude trof from the central Great Lakes into the southern
Appalachian Mtns by 12z Thurs. This phasing along with potent s/w
energy wl help in the deepening of sfc low pres over eastern VA,
while cool sfc high pres is anchored over northern Maine. Feel just
enough cold air remains trapped in deeper mtn valleys and midslope
areas, precip could start as a period of light wintry mix on Thurs.
Very minimal impacts anticipated, given the limited areal
coverage/duration. By 00z Friday mid/upper lvl trof becomes
negatively tilted over the Ohio Valley, while elongated sfc low pres
is stretching from near Erie PA to Atlantic City, NJ. Develop
south/southeast flow wl advect deep moisture into our cwa with
widespread rain developing by late Thurs into Thurs night associated
with initial waa surge. This synoptic scale lift is captured nicely
in the progged 850 to 700mb fgen fields from the NAM and associated
uvv`s output. Did note a weak ribbon of elevated instability with
MUCAPE values in the 100-250 J/kg over southern VT, so a rumble or
two of lightning is possible. Given the elongated sfc low pres
signature, progged 850mb winds are in the 45 to 55 knot range with
soundings indicating strongest winds near summit level with
localized gusts 25 to 35mph in favorable downslope areas along the
western slopes. As deep closed cyclonic circulation and associated
energy loft move directly overhead on Thurs night, expect additional
areas of rain to develop and rotate acrs our region. Given dynamics
and moisture advection, localized heavy downpours are possible, with
highest qpf amounts concentrated in the dacks and portions of the
central/southern Greens. Some shadowing from the White Mtns acrs the
NEK of VT, but as winds shift to the west/northwest on Friday, this
region wl make up for the rainfall. Rainfall generally in the 0.25
to 0.75 with localized amounts over 1.0 thru 12z Friday. Temps cool
into the upper 20s to mid 30s early Weds night, before warming as
winds and clouds increase by Thurs morning. Highs on Thurs mid 40s
to lower 50s with lows on Thurs night in the mid 30s to mid 40s.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 125 PM EDT Tuesday...Surface low pressure over Maine is
expected to occlude and slide northeast on Halloween as an upper
level trough crosses directly overhead of the forecast area, also
moving north and east. Precipitable water values will therefore be
on the decrease as cold air advection commences, especially as
Melissa grows farther and farther from influence. However, pwats
over northern New York and Vermont could still be as high 0.90-1.00"
throughout the day close to that upper low, resulting in likely
precipitation, especially along the international border and on
western and southwestern slopes.
We can expect 0.35-0.90" of new rainfall over the course of the day
with perhaps some snow mixing in at the highest elevations of the
Adirondacks later in the afternoon. Winds will also increase up out
of the west/southwest on Halloween as the gradient tightens behind
the occluding low and as a low level jet, 45-50 knots at 850mb,
noses into the area. Surface winds could be gusting as high as 25 to
30 mph for much of the forecast area, potentially highest on eastern
and northeastern slopes of the mountains due to downsloping. Higher
winds are possible on mountaintops, so conditions on the mountains
should be turbulent. Highs will be limited by a thick layer of
clouds, but should reach into the 50s around noon before dropping in
the afternoon due to cold air advection.
Halloween night, we`ll see precipitation lessen as low pressure
moves into the Canadian maritimes, but some measurable precipitation
is still likely in northern areas and western slopes of the
mountains. Up to a third of an inch of additional precip is
anticipated in some of these spots. Southwesterly winds are also not
expected to let up much at all, still gusting 25 to 30 mph at times,
once again strongest and most persistent on eastern slopes. Toward
dawn Saturday morning, we could even see gusts up to 35 mph. Cold
air advection is likely to continue overnight, though continued
clouds may keep lows from falling below seasonal averages in the
upper 20s to lower 40s. Snow is forecast across portions of the
Adirondacks and Greens generally above 1700-2500 feet.
Upslope precipitation looks to continue into the weekend, though it
should become much more scattered, showery, and limited to upslope
and mountain areas. Temperatures are expected to struggle to get
into the 40s and lower 50s each afternoon over the weekend and early
next week, and snow levels look to fall each night with lows in the
20s to mid 30s. Higher elevations could see some light snow
accumulations by early next week. Models look to bring in a frontal
boundary sometime next week as well, though agreement on timing and
strength of features is poor, so uncertainty remains moderate on
precipitation potential Monday onward.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
Through 00Z Thursday...VFR conditions currently prevail across
all terminals this evening under clear skies. Compared to this
afternoon, winds have trended lighter from the north with most
terminals around 5 knots or less. The main concern for aviation
during this forecast period will be the potential for any fog
and/or low stratus developing tonight, generally between 09Z to
13Z, although determining the exact locations of where any
reduced conditions is tricky. The greatest chances of IFR
conditions developing will be at KMSS, KSLK and KBTV, although
any terminal is not out of the question. After any fog
dissipates, VFR conditions are once again expected to prevail
across all terminals through the remainder of the forecast
period.
Outlook...
Wednesday Night: VFR. NO SIG WX.
Thursday: Mainly VFR, with local MVFR possible. Chance RA, Chance
FZRA.
Thursday Night: Mainly MVFR, with local IFR possible. Definite
SHRA.
Friday: Mainly MVFR, with areas IFR possible. Definite SHRA.
Friday Night: Mainly MVFR, with local IFR possible. Definite
SHRA.
Saturday: Mainly MVFR, with local VFR possible. Chance SHRA.
Saturday Night: Mainly VFR, with areas MVFR possible. Chance
SHRA.
Sunday: Mainly VFR, with areas MVFR possible. Slight chance SHRA.
&&
.EQUIPMENT...
The TYX radar is down until further notice after a hardware
failure occurred. Replacement parts have been ordered and will
be installed. There is no ETA on its return to service.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Taber
NEAR TERM...Taber
SHORT TERM...Taber
LONG TERM...Storm
AVIATION...Kremer
EQUIPMENT...BTV
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