390
FXUS61 KBTV 271823
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
223 PM EDT Mon Oct 27 2025
.SYNOPSIS...
High pressure will be building into our area tonight into Tuesday
with clearing skies and near normal temperatures. Lows tonight
will be in the upper 20s to upper 30s with highs in the upper
40s to mid 50s on Tuesday. A large system will impact the area
Thursday into Friday with widespread rainfall, gusty winds, and
cooler temperatures.
&&
.NEAR TERM /THROUGH TUESDAY/...
As of 217 PM EDT Monday...GOES-19 mid lvl water vapor loop shows
closed cyclonic circulation over eastern ME this aftn with pockets
of mid lvl moisture rotating acrs our cwa, while very dry air is
just west of our cwa. The fcst challenge tonight is cloud cover and
if any clearing develops, temps wl plummet quickly. Given 925mb to
700mb layer rh fields, feel best potential for clearing wl be acrs
the SLV and downslope areas of the lower CT River Valley and
portions of the CPV, while clouds linger acrs the trrn. In addition
to the clouds soundings support some llvl mixing with pres gradient
btwn departing low pres and building high pres, so have kept lows
close to guidance with values upper 20s to upper 30s and limited fog
potential. Low prob of fog with best potential right near sunrise
acrs the CT River Valley and patchy development in the SLV, but bl
winds of 3 to 6 knots should minimize threat. Tues is quiet
with 1032mb high pres building south toward the International
Border while dry air in the 1000-500mb layer is overhead and pw
values fall to near 0.25" by 00z Weds. Progged 925mb temps btwn
2-4C wl support highs upper 40s to mid 50s with upper 30s to mid
40s on summits. Light north/northeast winds of 3 to 7 mph.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 217 PM EDT Monday...Mid/upper lvl ridge builds acrs our cwa for
mid week with 1032mb high pres anchored just north of the
International Border. This general synoptic scale setup wl cause dry
conditions with seasonable temps acrs our fa. The probability for
areas of fog look better on Tues night, given lighter winds and
temps reaching cross over values as mostly clear skies prevail. Lows
in the 20s to mid 30s acrs our region. Weds wl feature plenty of
sunshine with deep dry layer directly overhead associated with
multiple layer ridging. Progged 925mb temps near 4C, support highs
mostly in the 50s, except l/m 40s acrs the summits. Moisture slowly
begins to approach our cwa by 12z Thurs associated with our next
full latitude system and associated sfc low pres. Have kept fcst dry
thru 12z Thurs with some increasing summit level winds toward
sunrise associated with strengthening 925mb to 850mb wind fields
from the east/southeast direction. Given increasing winds and
clouds, feel mid evening lows are expected with temps warming to
above freezing most areas by precip arrival time on Thurs.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 217 PM EDT Monday...The latter half of the week will feature an
amplified pattern as a deep upper low will slowly lift northeast at
strong high pressure decays and ambles off the Gulf of St. Lawrence.
South flow will be channeled between the upper low and ridging that
is shifting offshore well into the Arctic. Initially, there could be
some virga on radar as mid-level moisture arrives first. Theta E
progs indicate that the warm front will approach Thursday morning.
Gradients are likely to tighten as low pressure approaches the Great
Lakes region. Southeasterly flow will accelerate in response to the
approaching system, and we will likely observe gusty winds to 30 mph
in favored downslope regions of the northern Adirondacks and Green
Mountains. Anything beyond that, we`ll need to closely examine the
arrival of precipitation, and if pressures begin to fall near the
triple point of an occluded boundary, then that would limit
gradients.
Most precipitation will occur behind the warm front as it becomes
strongly occluded and moisture gets drawn towards the deepening
Great Lakes system, potentially approaching 980mb. Sharp frontal
forcing, excellent upper divergence, and 250-400 J/kg of CAPE
(mostly elevated) will add some convective elements. Raw
probabilistic guidance depicts a 30-50% chance of exceeding 1 inch
of rainfall in 24 hours. Post-processed NBM data suggests
probabilities close to 50-70%.
Of course, there`ll be more to come once we get into northwesterly
flow behind the system. Strong cold advection with deep moisture in
the wrap around will allow additional precipitation, especially
across northwestern slopes. Taking Thursday and Friday together, the
probability of 2" or greater from this storm will be about 20-40%.
We`ll happily take this. Deeper cold air is not expected to arrive
until Saturday or Sunday, though. Snow levels for Friday will likely
be around 3000-3500 ft, and then drop towards 2500 ft by Sunday.
However, moisture will begin departing with weak ridging setting in.
Temperatures will be relatively close to seasonal norms with mid 40s
to lower 50s in the day and mid 20s to mid 30s at night.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
Through 18Z Thursday...Prevailing surface conditions will be fairly
persistent for the next 24 hours. Generally north to northeast flow
will continue, outside terrain southeasterly winds about 23z to 13z
at KRUT. Wind speeds will generally remain 4 to 8 knots in the
daylight hours and 4 knots or less at night. Clouds will continue to
rotate southwards on the western periphery of deep low pressure
slowly moving towards the Gulf of Maine. Outside partial clearing,
ceilings will likely remain between 2500-5000 ft agl through the
period. Skies will trend clearer beyond 12z Thursday.
Outlook...
Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. NO SIG WX.
Wednesday Night: VFR. Slight chance SHRA, Slight chance FZRA.
Thursday: Mainly VFR, with local MVFR possible. Chance SHRA,
Slight chance FZRA.
Thursday Night: Mainly MVFR, with areas IFR possible. Definite
SHRA.
Friday: Mainly IFR, with areas MVFR possible. Definite SHRA.
Friday Night: Mainly IFR, with areas MVFR possible. Definite
SHRA, Definite FZRA.
Saturday: Mainly MVFR, with local VFR possible. Likely 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...Haynes
AVIATION...Haynes
EQUIPMENT...BTV
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