Charleston, Vermont Weather Forecast Discussion

370
FXUS61 KBTV 251158
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
758 AM EDT Thu Sep 25 2025
.SYNOPSIS...
Several rounds of rain showers with embedded heavier
downpours are anticipated today across northern New York and all of
Vermont. Rainfall amounts will vary from a quarter of an inch to
localized amounts over one inch possible. In addition, localized
southeast gap winds of 25 to 35 mph will be possible along the Green
Mountain Spine. Temperatures will only be in the 60s today, but
warmer and drier weather returns this weekend, including some highs
approaching daily records on Sunday. Nights may feature low clouds
and patchy dense fog, especially in valleys locations, into the
weekend.
&&
.NEAR TERM /THROUGH FRIDAY/...
As of 627 AM EDT Thursday...Just a quick morning update to
adjust rain chances today to better match what`s being reported
from ground truth and what the high res models are suggesting
for the day today. Hard to depict in PoPs, but thinking this
current wave will let up in a few hours and be replaced by
another round shortly after, that one a little more convective
in the afternoon warmth and instability.
Previous discussion...A closed upper level low pressure draped
across the Great Lakes and a surface low pressure system
crossing New England today will bring several rounds of rain
showers to the forecast area. Models continue to estimate
precipitable water values as high as 1.50-2.00 inches throughout
the day, warm cloud layer depths reaching around 11,000- 13,000
feet, and a 500mb level jet 75-100 knots nosing into the area
in the afternoon and evening. A warm frontal boundary moving
south to north over the course of the day will provide ample
forcing to produce showers with embedded heavier downpours. A
few rumbles of thunder are possible in the afternoon, but CAPE
values continue to look unfavorable for widespread convection.
Our forecast precipitation amounts are largely unchanged, though
there still exists a wide range in model guidance QPF. Thinking this
morning through tonight will feature 0.35-1.25" of rainfall with
localized higher amounts in heavy downpours and perhaps slightly
lower amounts in mild downslope shadowing. A low level jet around
850mb could reach up to 35-40 knots, which continues to indicate the
potential for localized gusts 25 to 35 mph along gaps in the Green
Mountains and in downslope winds on western slopes. Highs today will
be in the upper 60s to lower 70s, fairly seasonable despite the
rain.
Upper level trough will shift into the Ohio Valley overnight tonight
as the surface low pressure and core of moisture speed northeastward
and away from our area. We should see lingering showers thanks to a
weak trailing cold frontal boundary. Highest chance of showers is in
mountains and along international border, nearest to an upper
shortwave to our north. Conditions will remain mild and humid
overnight due to very weak cold advection with the potential for low
clouds and patchy fog developing and restricting visibilities on the
roads.
Propelling off mild temperatures Friday morning, Friday afternoon
temperatures are forecast to reach the 70s ahead of a secondary cold
front, though highs could end up being lower than forecast if we
have more widespread showers and clouds as an upper level shortwave
lifts north out of the Ohio Valley and passes near to our forecast
area. At the moment, it`s looking like these features could produce
a few additional showers, about 15-55% chance, though precipitation
amounts will likely be minimal.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY/...
As of 218 AM EDT Thursday...Increasing pressure, falling
temperatures, recent rainfall, light or calm winds, and breaks in
clouds could spell valley fog for Friday night as precipitation
chances decrease dramatically. Lows overnight could reach as low as
the 40s and lower 50s as the core of high pressure builds across
Quebec, Ontario, and northern New York, shifting eastward during the
day Saturday. This will result in a pleasant and mostly sunny day
with highs in the 70s.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 239 AM EDT Thursday...A prolonged dry spell is expected as
the southern fringe of the westerlies in the northern jet
stream returns to our region, promoting northwest flow and lack
of storminess. At the start of the period, there are slight
chances of showers in our far southern areas overnight Saturday.
This possible precipitation would be associated with a weak
coastal low that would only need to watched if it tracks on the
northern periphery of model spread.
Temperatures will initially be well above normal on Sunday, and
slightly less so on Monday, as low level west-southwest flow
transports air from the Midwest where a warm upper level ridge will
be centered. Mid level air will be more anomalously warm than the
low level temperatures related to the aforementioned ridge, which
should limit convective chances; whatever instability and terrain-
driven clouds develop should be capped by the warm air aloft.
A very weak, dry cold front will pass through in the Monday - Monday
night timeframe. Winds will flip to the north and will likely remain
that way through Wednesday as seasonably cool air filters into the
region and Canadian high pressure gradually builds into the region.
As such, each day will trend cooler than the day before, with
somewhat increasing spread as well as degree of cold air advection
varies amongst model guidance such that the cooldown could be more
modest or more substantial than forecast. Most likely high
temperatures by Wednesday will range through the low to mid 60s for
most locations, which would be near normal for this time of year.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
Challenging aviation forecast continues through this period. A
developing low pressure system over western New York this
morning will track right over the airspace between about 18Z
and 01Z, and during that period some heavier rain and periodic
IFR visibilities are expected. Both ceilings and visibilities
will be variable through this timeframe, then trend LIFR as calm
to light northwesterly flow and abundant moisture lead to very
low stratus and fog.
Currently a mix of all flight conditions, with a both ceilings
and visibilities fluctuating with showers that are moving
through all sites this morning except for MSS where LIFR
ceilings and only VCSH are present. Most of this round of rain
will taper off by 15Z, but ceilings will tend to remain
MVFR/IFR, except for RUT and BTV due to downsloping
southeasterly flow.
A southeasterly low level jet is currently strong enough to
produce a couple hours of LLWS at most sites in the through
about 19Z. Otherwise, winds will remain mainly 5 to 10 knots,
although stronger at RUT when southeast winds are at the
surface. Winds after 06Z will trend westerly/northwesterly and
remain light.
Outlook...
Friday: Mainly VFR, with local IFR possible. Chance SHRA.
Friday Night: VFR. Patchy BR.
Saturday: VFR. Patchy BR.
Saturday Night: VFR. Patchy BR.
Sunday: VFR. Patchy BR.
Sunday Night: VFR. NO SIG WX.
Monday: VFR. NO SIG WX.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Storm
NEAR TERM...Storm
SHORT TERM...Storm
LONG TERM...Kutikoff
AVIATION...Kutikoff

NWS BTV Office Area Forecast Discussion