Concord, Vermont Weather Forecast Discussion

963
FXUS61 KBTV 250641
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
241 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 218 AM EDT Thursday...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 /07Z THURSDAY THROUGH MONDAY/...
Challenging aviation forecast through this period. Both ceilings and
visibilities will tend to be somewhat variable but it is hard to
pinpoint categorical changes while waves of showers blossom out
ahead of a low pressure system that will cross the airspace between
18Z and 00Z from southwest to northeast. One wave is moving through
now, with spotty light showers, but more widespread light rain is
expected to affect all sites generally between 10Z and 20Z with some
embedded heavier elements possible, especially at RUT. Have
prevailing 4SM visibilities but would expect some periodic IFR
visibilities will occur. At the same time, ceilings which are a mix
of VFR and MVFR between about 1000 and 3500 feet will trend lower,
resulting in a mix of MVFR and IFR conditions. Generally after 12Z
probabilities of IFR conditions increase at most sites, into the 40-
50% range. There is also a low (about 5-15%) chance of thunder,
slightly higher at northern New York terminals and RUT, during the
13-19Z period, but most of the heavier showers will not produce
lightning.
A southeasterly low level jet still is favored to lift
northeastward with enough shear to mention a couple hours of
LLWS at most sites in the 15Z to 20Z period, with timing
trending a little faster compared to the previous TAF package.
Otherwise, winds will remain mainly 5 to 10 knots, although
stronger at RUT when southeast winds are at the surface. After
00Z, with decreasing winds and rain tapering to drizzle or
ending, would expect IFR conditions may linger or redevelop due
to BR. Have not included that detail in TAFs at this time due to
uncertainty and focus on the first 12 hours.
Outlook...
Friday: Mainly VFR, with local IFR possible. Slight chance SHRA.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. NO SIG WX.
Saturday Night: VFR. NO SIG WX.
Sunday: VFR. NO SIG WX.
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