Swanton, Vermont 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

441
FXUS61 KBTV 200635
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
235 AM EDT Thu Aug 20 2026

.WHAT HAS CHANGED...
As of 234 AM EDT Thursday...

No significant changes.

&&

.KEY MESSAGES...
As of 234 AM EDT Thursday...

1. Dry before showers return late Saturday and Sunday.

2. Upper troughing and slightly cooler weather arrive for
Monday into Tuesday of next week along with a few showers, after
which drier and warmer conditions return by the mid to late week
time frame.

&&

.DISCUSSION...
As of 234 AM EDT Thursday...

KEY MESSAGE 1: Dry and relatively seasonable conditions will prevail
through the end of the week with low humidity. Highs will be in the
70s and low 80s and lows will be in the 40s and 50s away from Lake
Champlain. A primary area of low pressure will develop over the
Great Lakes on Saturday and a secondary low will try to form off the
Mid-Atlantic coast. The primary low looks to track northeast and
into Quebec, while the low off the Mid-Atlantic looks to travel up
the eastern seaboard. The idea is that these two lows should
eventually phase over Quebec or Atlantic Canada, past our region.
Showers are likely Saturday night over northern New York from the
primary low, and these will gradually track eastward. Showers are
possible late Saturday into Saturday night in southern areas from
the secondary low, but whether these can reach the region or stay
south is uncertain. Some showers are expected region-wide on Sunday
as the parent low passes east. While a couple rumbles of thunder are
possible during the day, instability will be very low due to a lack
of consistent sunshine and a cooler airmass. GEFS/EPS/CMCE
probabilities of a half inch of rain are between 25-75 percent, with
the lowest values over central and northern Vermont which look to
get sandwiched between the two lows. Probabilities of an inch are
below 25 percent.

KEY MESSAGE 2: Model consensus remains in decent agreement showing a
broad longwave trough pulling through the eastern quarter of the
nation early in the long term portions of the forecast. The best
chance of showers/isolated thunder comes Sunday night into Monday
with passage of an accompanying surface trough/front. Sensible
conditions trend drier from Tuesday onward with slightly warmer
temperatures as upper trough pulls out to the northeast and is
replaced by broad surface high pressure. That said, not a whole lot
of airmass change is shown across these features over time as
surface pressure gradients and synoptic-scale thermal advective
processes remain light. As such, daily highs to generally range from
the mid 70s to lower 80s with overnight lows in the upper 40s
through the 50s through the period with "coolest" day being Monday.
So generally quite pleasant for any late summer outdoor activities.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
Through 06Z Friday...Patchy MVFR/IFR in BR at selected terminals
through 12Z (MPV/SLK/MSS/EFK), otherwise VFR expected through
the period under light winds less than 10 kts. SCT/BKN cigs in
the 015-045 AGL range at SLK/EFK overnight, otherwise mainly SKC
with just some passing high clouds AOA 200 AGL.

Outlook...

Friday: VFR. Patchy BR.
Friday Night: VFR. NO SIG WX.
Saturday: VFR. Slight chance SHRA.
Saturday Night: Mainly VFR, with local MVFR possible. Slight
chance SHRA.
Sunday: Mainly MVFR, with areas VFR possible. Likely SHRA, Slight
chance TSRA.
Sunday Night: Mainly IFR, with areas MVFR possible. Chance SHRA,
Slight chance TSRA.
Monday: MVFR/IFR conditions possible. Chance SHRA, Slight chance
TSRA.

&&

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

&&

$$

WHAT HAS CHANGED...Myskowski
DISCUSSION...JMG/Myskowski
AVIATION...JMG