071
FXUS61 KBTV 171652
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
1252 PM EDT Wed Jun 17 2026
.WHAT HAS CHANGED...
As of 226 AM EDT Wednesday...
Confidence has increased for strong to severe thunderstorms on
Thursday afternoon.
&&
.KEY MESSAGES...
As of 226 AM EDT Wednesday...
1. A pair of systems expected to track through today and
tomorrow. The second on Thursday will bring more potential impacts
of winds and thunderstorms with embedded heavy rain and damaging
winds.
2. Showery, breezy conditions are expected for the early
portion of the weekend.
3. A low pressure system will likely bring widespread rain to
the region on Monday, followed by seasonably warm temperatures next
week.
&&
.DISCUSSION...
As of 226 AM EDT Wednesday...
KEY MESSAGE 1: Today will open up with increasing clouds and some
showers and thunderstorms as an upper trough lifts northeast.
Although it`s not the strongest trough, it`s managed nighttime
convection in the Great Lakes region. South flow today should allow
for moderation into the 70s to near 80 today. Despite somewhat dry
dewpoints, good lapse rates in tandem with the upper trough should
produce scattered to numerous shower activity. Winds aloft are not
strong, but with dry air entrainment, there should be some
acceleration of winds in any thunderstorms. Looking upstream at
Buffalo, NY, showers and storms have produced gusts around 30-35
knots. So that could be in the cards for us too.
Thursday`s activity will be more significant. A sub-990mb low will
pass near to north of Ottawa. The level of synoptic support is quite
strong with a near 130 knot upper level jet nosing in.
Isentropic ascent, some elevated instability, and large scale
lift will result in a swath of moderate to heavy rain as the
warm front races northeast. After the warm front lifts out of
the region, the question continues to be how much wind will be
able to mix to the surface after any rainfall. Winds of 45-50
knots descends to about 1500-2000 ft above ground levels. So it
will not take much to mix winds to the surface; however, the
warm sector has trended towards continued convection embedded
within the warm sector as occlusion quickly takes place late
Thursday morning into the afternoon. For now, max wind gusts are
depicted reaching 30-40 mph, and locally up to 45 mph near
Malone, New York. With all the leaves on the trees, this could
pose a greater likelihood for downed branches. Isolated to
scattered power outages will be possible on Thursday.
Next on Thursday will be the convection: The Storm Prediction Center
has upgraded the Severe Weather Outlook to a Slight Risk (Level 2 of
5) for isolated strong to severe thunderstorms. The situation
involves high shear in the 0-6km layer of 45-55 knots while
instability of 500-750 J/kg and somewhat low equilibrium levels make
it likely that activity remains short and tilted. CAMs are split on
timing as well, and that will affect how much instability convection
has to develop. With the fast flow, the main concern will be whether
any storms can mix down the strong winds to the surface, and that
will be the primary severe weather hazard. Given such a strong
surface low, excellent inflow from southeast flow, and the quick
westerlies aloft, rotating updrafts are possible. The HREF/REFS
indicates some helicity tracks through the region as well. However,
the strong shear mentioned before may tilt updrafts too much to
sustain organized convection. The system will track east Thursday
evening with storms clearing the region.
KEY MESSAGE 2: Thursday`s strong low pressure gets stuck near Quebec
City for a few days with an upper low nearby. This will impart
breezy west-northwest winds with occasional showers. The greatest
chances will be along the international border given proximity to
the surface low. Both days feature some tall, skinny CAPE profiles.
Given that fast flow will continue with some good low-level lapse
rates, a few showers could produce gusty winds, but none are
anticipated to be particularly strong. Temperatures will trend
cooler heading into the weekend with a seasonable day Friday before
the core of the coldest air arrives Saturday placing temperatures in
the lower 60s to lower 70s.
KEY MESSAGE 3: A deep trough over the Canadian maritimes will linger
through the weekend bringing showers and the occasional thunderstorm
to the Northeast before finally shifting out into the Atlantic Ocean
early next week. There remains the potential for a potent low
pressure system to pass to our south which would produce widespread
rain and embedded thunderstorms across the region on Monday and
Monday night. Deterministic models continue to disagree on
exact track and timing of this system, with 40-65% chance of
measurable precipitation Monday afternoon and 25-50% chance of a
half an inch within 24 hours during this period. With so much
disagreement in the deterministic global models, temperatures
early next week may depend on precipitation, but the majority of
models at this point seem to be suggesting temperatures could
increase to and even reach slightly above seasonal normals by
midweek with highs in the upper 60s to lower 80s and lows in the
upper 40s to lower 60s.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Through 18Z Thursday...VFR conditions will persist through 12Z
before CIGs lower as widespread showers spread over northern New
York and Vermont. 18-23Z showers and isolated thunderstorms are
favored with highest chances of TSRA over northern New York as a
trough swings through.
Largest threat to aviators 12-18Z Thursday will be strong SFC
gusts associated with a tight pressure gradient and LLWS ahead
of and along a front moving through the region. Can`t rule out
some strong convection either along the front, but will wait to
include in TAFs until they are closer. CIGs lower at least to
MVFR as gusts increase in excess of 30kts for most terminals.
Outlook...
Thursday: Mainly VFR, with areas MVFR possible. Windy with gusts
to 35 kt. Definite SHRA, Chance TSRA.
Thursday Night: VFR. Slight chance SHRA.
Friday: VFR. Slight chance SHRA, Slight chance TSRA.
Friday Night: Mainly VFR, with local MVFR possible. Chance SHRA.
Saturday: Mainly VFR, with areas MVFR possible. Likely SHRA,
Slight chance TSRA.
Saturday Night: Mainly VFR, with local IFR possible. Chance SHRA.
Sunday: Mainly VFR, with areas MVFR possible. Chance SHRA, Slight
chance TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Wind Advisory from 8 AM to 8 PM EDT Thursday for VTZ001>009-
011-016>020.
NY...Wind Advisory from 8 AM to 8 PM EDT Thursday for NYZ026>031-
034-035-087.
&&
$$
WHAT HAS CHANGED...Haynes
DISCUSSION...Storm/Haynes
AVIATION...Boyd
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