Williston, Vermont 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

722
FXUS61 KBTV 111936
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
336 PM EDT Wed Jun 11 2025

.SYNOPSIS...
A brief period of southwest gusty winds is expected this
evening into overnight. Winds in the St. Lawrence Valley are
expected to gust as high as 35 mph and a Lake Wind Advisory is
in effect for gusts up to 25 knots over Lake Champlain. A few
overnight light rain showers are also possible as a cold front
moves through. Thursday and Friday will be mostly dry with
seasonable temperatures and low humidity. Rain chances return
Friday night into the weekend.

&&

.NEAR TERM /THROUGH THURSDAY/...
As of 320 PM EDT Wednesday...Zonal westerly flow will continue,
allowing a brief embedded vort max to ripple through this
evening/early overnight. A west/southwesterly low-level jet will
strengthen overhead this evening ahead of the shortwave, maxing
out near midnight tonight at 40 to 50 knots at the 850 mb
level. The nocturnal timing of the jet will prevent the
strongest momentum aloft from getting mixed down, but some areas
will still become breezy this evening into early overnight.
Strongest wind gusts will be over the Saint Lawrence Valley,
where channeled southwesterly flow will allow for gusts 25 to
35 mph. Gusts over the remainder of the area will be in the 20
to 25 mph range. A Lake Wind Advisory is in effect for the
overnight hours for winds 15 to 25 knots on Lake Champlain. In
addition, winds over the mountain summits will peak above 45 mph
tonight.

The passage of the shortwave trough will also lead to the
development of some isolated to scattered light showers overnight,
mainly over our northern counties.  Precipitation amounts will be
very light, and overall no impacts expected from any of the brief
passing showers. Precipitation amounts in areas that do see a shower
will only be a few hundredths of an inch. Partly to mostly cloudy
skies overnight will keep lows moderated in the mid 50s to mid 60s.

Along with the passage of the shortwave aloft overnight, a surface
front will move through Thursday morning. This front will sweep any
smoke aloft/haze from Canadian wildfires out of the area by Thursday
afternoon.  Partly cloudy skies are expected Thursday with just the
development of some fair weather cumulus expected over topography.
Have maintained some PoPs in the 5 to 20 percent range Thursday over
our northern counties as vorticity maxima continue to ripple into
southern Quebec within the northwest flow aloft, but any showers
would again be light and isolated in nature.  Highs Thursday will be
in the 70s for most areas, with some of our valleys in central and
southern VT potentially reaching 80.  Distinct dry layer on forecast
soundings between 500 and 800 mb should allow drier dewpoints to mix
down during midday hours, and have trended dewpoint forecast towards
the 10th percentile NBM for Thursday afternoon.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
As of 320 PM EDT Wednesday...Dry and cool weather is expected on
Friday as ridge of surface high pressure builds over the area from
Canada. The day will start out sunny with increasing clouds during
the afternoon. Winds will be light out of the north. Maximum
temperatures will top out below seasonal normals, generally ranging
through the 60s with some low 70s in larger valleys. Rain chances
will increase Friday night into Saturday as a quasi stationary
frontal zone develops across New York and into southern New England.
There is still some uncertainty as to where this boundary will set
up, but at this time looks like we can expect some precipitation on
Friday night, and we`re carrying likely probabilities for
precipitation at that time. Mainly light stratiform precipitation is
expected with rainfall totals from Friday night into Saturday
ranging from a few hundredths of an inch in the St Lawrence valley
up to around three tenths of an inch. Models still indicating a
potential for some elevated instability, but have not included
mention of thunder due to low chances at this time. Our Friday night
minimum temperatures will be in the upper 40s to lower 50s, then
maximum temperatures on Saturday will range through the 60s.
Probability for precipitation will lower through the day Saturday.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 320 PM EDT Wednesday...Additional shortwave energy passing
overhead will bring continuing chances for showers on Saturday night
into Sunday, with showers winding down Sunday afternoon. At this
time longer range models show a return to some drier weather for
later Sunday through about Tuesday, then a turn towards more active
weather. But, there is a not a lot of model to model or run to run
consistency at this time. The week will start out with below
seasonal temperatures, then warming up towards the end of next week.
Wednesday looks to be the next best timeframe for some showers.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
Through 18Z Thursday...We continue to observe VFR conditions
throughout the forecast area with main impacts to the TAFs
being wind gusts that will ramp up going into the
evening/overnight hours. A 40 to 50 knot low-level jet will peak
overhead between this evening and midnight, which will allow for
some periods of LLWS. LLWS will affect NY TAF sites
predominantly between 00Z and 08Z, and affect eastern VT TAF
sites between 06Z and 12Z. Surface winds from the
southwest/south will pickup this evening, gusting generally
between 15 and 25 knots at TAF sites, and then diminish in the
early morning hours. Some additional gusts 10 to 20 knots will
develop after 14Z on Thursday. Ceilings will remain at mainly
VFR levels, although some overnight deterioration to MVFR levels
is expected at KMSS and KSLK. Some overspreading HZ from
Canadian wildfire smoke is also expected, but is not forecast to
reduce visibilities below 6SM in the next 24 hours.

Outlook...

Thursday Night: VFR. NO SIG WX.
Friday: VFR. NO SIG WX.
Friday Night: Mainly VFR, with local MVFR possible. Chance SHRA.
Saturday: Mainly MVFR, with areas VFR possible. Chance SHRA.
Saturday Night: Mainly MVFR, with local IFR possible. Chance
SHRA.
Sunday: Mainly MVFR, with areas VFR possible. Slight chance SHRA.
Sunday Night: Mainly VFR, with local MVFR possible. Slight chance
SHRA.
Monday: VFR. Slight chance SHRA.

&&

.MARINE...

A Lake Wind Advisory is in effect for this evening with
southwest winds 15 to 25 knots. Winds will increase the evening
and peak near midnight, then become westerly and diminish going
into the early morning hours. Waves will be 1 to 2 feet, except
1 to 3 feet in the Broad Waters.

&&

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

&&

$$
SYNOPSIS...Duell
NEAR TERM...Duell
SHORT TERM...Neiles
LONG TERM...Neiles
AVIATION...Duell
MARINE...NWS BTV