Castleton, Vermont Weather Forecast Discussion

026
FXUS61 KBTV 200631
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
231 AM EDT Sat Sep 20 2025
.SYNOPSIS...
Areas of frost and freeze conditions will continue this morning
and again tonight. Temperatures will fall into the upper 20s to
mid 30s in most spots, though remaining closer to 40 degrees
near Lake Champlain. Otherwise, the weather will remain dry
through the weekend, with some increased shower chances for
early next week.
&&
.NEAR TERM /THROUGH SUNDAY/...
As of 205 AM EDT Saturday...The Frost Advisory/Freeze Warning headlines
remain in place through this morning, with additional expanded
Frost Advisory/Freeze Warnings in effect from midnight tonight
to 8 AM Sunday.
Clear skies will remain dominant today with high pressure nosing
south out of Canada. The nearest clouds are currently found
across far western New York which has allowed for efficient
radiational cooling across most of the area. Temperatures sit in
the low to mid 30s for most of the region with values in the
upper 40s closer to Lake Champlain. Plenty of sunshine will be
felt by all today although temperatures will be on the cooler
side. Highs today will only be in the low to mid 60s, with
perhaps some upper 60s across far southeastern Vermont. Winds
will be on the calm to light side, mainly 5-10 mph, with the
higher of that range in the Champlain Valley from localized
channeling effects. It will continue to be quite comfortable
with the arriving air mass on the drier side; relative
humidities will be near critical fire weather thresholds around
30% for this afternoon. While fire weather concerns will be low
due to lower winds, several areas have burns bans due to the
ongoing drought, so continue to observe local ordinances where
applicable.
Tonight will be once again on the cold side, although not
unusually cold for this time of year. The first freeze of the
year is typically September 21st for the Adirondacks. Tonight
should be colder than last night with temperatures falling to 25
to 30 degrees in the Adirondacks and northeastern Greens.
Closer to Lake Champlain, temperatures will fall to the upper
30s. Generally if you do not live within 5 miles of Lake
Champlain, you should expect widespread frost conditions with
freeze conditions in the Adirondacks and Northeast Kingdom. Some
of the more cold prone locations of the Adirondacks could drop
as low as the low 20s tonight.
Sunday will see a gradual warming trend with high pressure
drifting east and southerly flow becomes more dominant.
Temperatures will rise to the low to mid 70s with mainly clear
skies to start, though a few mid to high clouds may build in
for the afternoon.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY/...
As of 205 AM EDT Saturday...Sunday night will see generally
increasing cloud cover ahead of an approaching cold front by
Monday. Cloud cover should keep Sunday night temperatures on the
more mild side compared to prior nights with lows in the 40s to
mid 50s. Areas in eastern Vermont should see clouds more delayed
so lows in the upper 30s to low 40s seem more reasonable. By
Monday a trough begins to ride along the departing high with
more broken to overcast skies by the afternoon. A few isolated showers
will accompany this boundary across northern New York by early
Monday. Temperatures will largely be in the 70s with isolated
shower chances continuing through the afternoon in northern New
York. Only a few hundreths are expected with any showers, mainly
across the St. Lawrence Valley through Monday afternoon.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
As of 205 AM EDT Saturday...The strong ridge that has provided our
CWA with full sunshine and fall-like conditions, moderating quite
nicely Sunday and early next week, will slide east early this
week to allow a northern stream system to slowly traverse
Ontario/Quebec and our CWA late Monday- Tuesday. The initial
shortwave hangs around the Great Lakes awaiting another system
ejecting across the Rockies to eventually develop a closed low
across the Plains and Ms Rvr Vly mid to late week and possibly
influence our region late week or next weekend.
The initial energy that I mentioned brings some showers late Monday
(western areas) and Monday night - Tuesday elsewhere. I`m thinking
initially there is decent coverage but as some energy stays west and
eastern Quebec shortwave digs across Tuesday-Wednesday that the
atmosphere stretches and moisture advection becomes NIL with
instability/terrain induced -shra develop what whatever moisture
remains and given how dry things are...I would lean toward drier
scenario and have with collaboration lowered guidance pops and kept
more inline with previous forecast.
Trends have been steady with probabilities of 48 hour precipitation
greater than 0.5 inches Monday through Tuesday currently are around
30-40% for northern New York and the northern Greens, around 20%
elsewhere. 48 hour probabilities of greater than 0.25 inches are
40-50% across the CWA, just slightly drier, esp eastern VT.
Basically some welcomed rainfall, but far from what is needed and
wouldn`t even characterize it as beneficial.
It looks like some shortwave ridging between the systems mentioned
above for Wed ngt-Thu and then timing issues and actual position of
closed low. If the closed low is close enough to CWA then a chc of -
shra late Friday or holding off until the weekend. If the upper low
is displaced more to the southwest, then mainly dry.
Temperatures this week will be seasonable and not expecting any
frost-freeze like this weekend.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
Through 06z Sunday...VFR conditions will continue due to very
dry air pressing into the region. While surface winds will
trend calm overnight, winds just off the surface will remain
10-15 knots. When combined with limited low-level moisture, fog
is not anticipated for KSLK but have maintained VCFG at MPV
09Z-12Z with low confidence in nearby fog. Clear skies and
returning north to northwest winds of 5 to 8 knots is expected
beyond 12z, then diminishing again after 22Z.
Outlook...
Sunday: VFR. NO SIG WX.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. Chance SHRA.
Monday Night: Mainly VFR, with local MVFR possible. Chance SHRA.
Tuesday: Mainly MVFR, with areas VFR possible. Chance SHRA.
Tuesday Night: Mainly MVFR, with areas VFR possible. Chance SHRA.
Wednesday: MVFR/IFR conditions possible. Chance SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Frost Advisory until 8 AM EDT this morning for VTZ002-003-
     006>008-010-016-017.
     Frost Advisory from midnight tonight to 8 AM EDT Sunday for
     VTZ002-005-009>011-016>021.
     Freeze Warning until 8 AM EDT this morning for VTZ004.
     Freeze Warning from midnight tonight to 8 AM EDT Sunday for
     VTZ003-004-006>008.
NY...Frost Advisory until 8 AM EDT this morning for NYZ026-027-029-
     034-087.
     Frost Advisory from midnight tonight to 8 AM EDT Sunday for
     NYZ026>029-034-035-087.
     Freeze Warning until 8 AM EDT this morning for NYZ030-031.
     Freeze Warning from midnight tonight to 8 AM EDT Sunday for
     NYZ030-031.
&&
$$
SYNOPSIS...Danzig
NEAR TERM...Danzig
SHORT TERM...Danzig
LONG TERM...SLW
AVIATION...SLW

NWS BTV Office Area Forecast Discussion