Swanton, Vermont 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

435
FXUS61 KBTV 161736
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
136 PM EDT Mon Jun 16 2025

.SYNOPSIS...
Temperatures and humidity increase this week with conditions
becoming uncomfortable by midweek. Otherwise, daily afternoon
shower chances are expected with thunderstorms chances
increasing mid week. Early indicators are pointing at non-zero
chances for localized heavy rainfall out of a few stronger
storms on Thursday.

&&

.NEAR TERM /THROUGH TUESDAY/...
As of 126 PM EDT Monday...No significant changes with this
update. Clouds continue to expand in coverage, particularly
over the higher terrain. Not seeing a lot of shower activity at
this point, but still expect a few showers will develop later
this afternoon. Temperatures are currently in the mid 70s to
around 80F, with another couple of degrees of warming still
possible. The forecast has this all covered, so just made a few
tweaks to incorporate the latest surface observations and
satellite imagery.

Previous discussion...Main deviation from the previous forecast
was to decrease shower chances this afternoon with high
pressure beginning to slide eastward. Latest guidance keeps the
ridge axis towards the North Country a little longer resulting
in trimming chances back a bit. Still some isolated to scattered
showers are possible mainly over northern New York this
afternoon and evening. Also of note, high temperatures will
trend warmer with southerly return flow bringing increasing dew
points and SFC-850mb temperatures; highs in the mid/upper 70s to
around 80 degrees are expected today and Tuesday while dew
points increase from the 50s today to around 60 Tuesday. With
the breakdown of the ridge and a quasi- stationary boundary
draped over the Northeast, shower and thunderstorms chances
increase Tuesday afternoon. The focus for convection will be
more towards the St Lawrence Valley where a passing trough will
help steepen mid level lapse rates adding a trigger to
compliment any surface based instability. For southern Vermont
and central Adirondacks, showers will be more pervasive as
energy rides along the stationary boundary with isentropic lift
being the primary mechanism for showers.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/...
As of 337 AM EDT Monday...Continued warming and increasing humidity
will be the main theme of the short term. Residual moisture advected
from passing shortwaves earlier in the day Tuesday will keep shower
chances through Tuesday night, with the best chances in south-
central Vermont and along the spine of the Greens. PoPs are
generally 30-50% through Tuesday night into Wednesday. Although
chance to likely PoPs are forecasted, precipitation amounts are
fairly light with only a few hundreths to a tenth expected.
Temperatures Tuesday night will only fall into the low to mid 60s
which is nearly 10 degrees warmer than seasonal norms. Continued
open wave energy riding over a subtle ridge on Wednesday will lead
to additional diurnally driven showers, particularly in the
Adirondacks and central Vermont. Models indicate weak instability
development with temperatures reaching into the mid 80s with
dewpoints in the mid to upper 60s. However, thunderstorm chances
areawide will be limited by low lapse mid-level lapse rates near 5C
and weak shear. Any thunderstorms and showers that do develop will
likely contain pockets of moderate rain with probabilities of PWATs
greater than 1" near 70%. Furthermore, surface winds will be light
which could lead to slow-moving storms which may enhance localized
rainfall amounts.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
As of 337 AM EDT Monday...Unsettled weather from a slow moving trough
will keep the heat and humidity in the region for much of late week.
A subtle ridge will begin to break down Wednesday night into
Thursday as a cold front approaches the region. Temperatures
Wednesday night will remain warm only falling into the mid to upper
60s. Heat and moisture will continue to stream into the region on
Thursday with dewpoints reaching into the mid to upper 60s and highs
in the low to mid 80s. Given the heat and moisture, and associated
forcing from the cold front, instability and thunderstorm
development is likely. The ECMWF and GFS deterministic models are in
pretty good agreement with 2 potential rounds of showers and
thunderstorms on Thursday. These thunderstorms could potentially be
strong and contain heavy rain with shear around 40 kts, and
probabilities of PWATs greater than 1.5" between 70-90% across
northern Vermont and New York. These PWAT anomalies are 150-175% of
normal. As a result of the potential for heavy rains, WPC has kept
the entire region in a Marginal Risk for Excessive Rainfall. One
limiting factor to any potential strong thunderstorms is that cloud
cover will be abundant ahead of the front which could keep a lid on
any strong to severe storm development.

After the front crosses through Thursday afternoon, the boundary
looks to stall briefly on Friday which will keep shower and
thunderstorm chances in the area. A brief respite from the heat and
moisture is to follow the boundary Friday night into Saturday as
most of the area should be on the north (cold) side of the boundary.
However, strong ridging looks to begin building in by the end of the
weekend with temperatures returning to the mid to upper 80s.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
Through 18Z Tuesday...VFR conditions with SCT-BKN ceilings AOA
3500 ft to prevail through at least the first half of the TAF
forecast, then lowering ceilings to MVFR at all terminals by 12z
Tue. A few afternoon showers are possible, but coverage will be
too isolated to include a mention in TAFs at this time. Ceilings
lower with increasing moisture overnight, reaching 1500-2500 ft
by 12z Tue and remaining so thereafter. South winds 5-10 kt
with localized gusts to 20 kt this afternoon, subsiding to
around 5 kt after 00z Tue.

Outlook...

Tuesday Night: Mainly VFR, with local IFR possible. Chance SHRA.
Wednesday: Mainly VFR, with local IFR possible. Chance SHRA,
Slight chance TSRA.
Wednesday Night: VFR. Chance SHRA.
Thursday: VFR. Likely SHRA, Chance TSRA.
Thursday Night: Mainly VFR, with local IFR possible. Chance SHRA,
Slight chance TSRA.
Friday: Mainly VFR, with local MVFR possible. Chance SHRA, Slight
chance TSRA.
Friday Night: Mainly VFR, with areas MVFR possible. Slight chance
SHRA.
Saturday: Mainly VFR, with local MVFR possible. Chance SHRA.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.

&&

$$
SYNOPSIS...Boyd
NEAR TERM...Boyd/Hastings
SHORT TERM...Danzig
LONG TERM...Danzig
AVIATION...Hastings