156
FXUS61 KBTV 170743
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
343 AM EDT Sun May 17 2026

.WHAT HAS CHANGED...
As of 254 AM EDT Sunday...

Winds this afternoon were increased marginally across Lake
Champlain.

&&

.KEY MESSAGES...
As of 254 AM EDT Sunday...

1. Unseasonably warm temperatures continue this weekend while
lake and river water temperatures remain dangerously cold.
Breezes on Lake Champlain may result in some rough lake
conditions through mid week.

2. Temperatures continue to trend well above seasonal averages
Monday through Wednesday with humidity building and highs in
the mid 70s to 80s each afternoon.

3. Thunderstorm chances return late Tuesday through Wednesday as
a front moves through the region.

4. Seasonably cool and dry conditions are expected for the
later half of next week.

&&

.DISCUSSION...
As of 254 AM EDT Sunday...

KEY MESSAGE 1: The combination of warm temperatures above 70
degrees and cold water temperatures present a hazard to those
recreating on area lakes and rivers. Water temperatures in the
40s will promote concerns for hypothermia and cold water shock
despite the pleasant air temperatures. This is a deceptive
hazard and has resulted in deaths from those enticed to take a
dip to cool off.

Winds will present another recreation hazard this week with flow
channeling down the champlain valley as a series of impulses
increase 925-850mb flow with strong mixing from warmer than
usual temperatures. Today, there could be a brief period this
afternoon where northwesterly gusts increase across the lake
supporting increasing wave heights especially towards the
southern end of the lake and towards Shelburne Bay. Flow
increases aloft Monday through Wednesday and turns more
southerly. It`s looking more probable that there will be periods
of conditions that will exceed lake wind advisory thresholds.

KEY MESSAGE 2: Unusually warm conditions persist and the anomaly
increases Monday through Wednesday as 925mb temperatures are
favored to warm into the 20-26C range due to increased south to
southwesterly flow aloft. The hottest day will be Tuesday with
highs in the 80s. Warmest locations may be east of terrain as
flow aloft turns more southwesterly resulting in some
compressional warming downslope off of terrain. Heat will
continue with cloud cover increasing as a front moves through
the region Tuesday night and early Wednesday. The front will
provide relief, but timing of its passage will be instrumental
with southern locations and portions of the Champlain Valley
likely warming into the upper 70s to low 80s. Fortunately,
overnight temperatures will cool into the 50s and 60s providing
some relief. Thunderstorms and rain showers Tuesday afternoon
may also blunt highs for locations that receive showers.

KEY MESSAGE 3: With building heat and humidity, thunderstorm
chances will increase Tuesday afternoon and evening. Model CAPE
shows the sharpest gradient across southern Vermont extending
northward up the Champlain Valley. It`s feasible to see
500-1000J/kg of CAPE for Tuesday afternoon as dewpoints climb
well into the 50s to low 60s. Temperatures in the 80s,
dewpoints in the upper 50s to low 60s, and some projected wind
shear ranging 30-40kts are highlights that suggest some
potential for a few strong storms. We`ll be watching how the
movement of the ridge axis evolves over the next couple of days
to assess storm potential further.

Chances continue Tuesday night into Wednesday as a front drops
out of Canada. There are some questions on timing of the front
will be critical in determining concerns for strong
thunderstorms. Should the front be delayed, the potential for
stronger storms would increase during the day on Wednesday. As
it stands now, the projections are for a partial passage through
portions of northern New York and northern Vermont overnight
with southern Vermont remaining in the warm sector during the
day on Wednesday. For now, this is a "keep an eye on the
forecast" scenario and not a foregone conclusion that strong
storms will occur. However, heating will support potential for
at least garden variety thunderstorms for much of Vermont.

KEY MESSAGE 4: Surface high pressure looks to build into the region for
the later half of the week, bringing mostly dry and seasonably cool
temperatures. High temperatures look to climb into the 60s most
afternoons, with overnight lows generally in the 40s. Temperature
trends will need to be monitored as we get closer, especially for
any frost concerns as the growing season goes into effect for the
entire region. Overall, it looks like a fairly pleasant stretch of
weather to round out the week ahead.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
Through 06Z Monday...VFR conditions are expected to prevail at
most terminals over the next 24 hours as skies trend clear
behind a weak frontal boundary. The only exception will be a
period of MVFR ceilings at KSLK through the overnight hours,
with ceilings generally between 1500 and 2500 ft AGL. THese
clouds are expected to erode towards daybreak, with all
terminals VFR by 12Z or so and remaining that way throughout the
remainder of the forecast period. West winds will continue to
trend more northwesterly over the next several hours, with gusts
of 20 knots or so expected through the afternoon. Some LLWS is
expected to linger at terminals for the next several hours as a
low level jet continues to exit the region.

Outlook...

Monday: VFR. NO SIG WX.
Monday Night: VFR. Slight chance SHRA.
Tuesday: VFR. Chance SHRA, Chance TSRA.
Tuesday Night: Mainly VFR, with local MVFR possible. Chance SHRA,
Slight chance TSRA.
Wednesday: Mainly VFR, with local MVFR possible. Likely SHRA,
Slight chance TSRA.
Wednesday Night: VFR. Slight chance SHRA.
Thursday: VFR. NO SIG WX.

&&

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

&&

$$

WHAT HAS CHANGED...Boyd
DISCUSSION...Kremer/Boyd
AVIATION...Kremer