067
FXUS61 KBTV 132344
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
744 PM EDT Sat Jun 13 2026
.WHAT HAS CHANGED...
As of 242 PM EDT Saturday...
Increased the winds tomorrow afternoon with better mixing potential.
Have also kept gusty winds and heavy rain wording within any
thunderstorm chances tomorrow afternoon.
&&
.KEY MESSAGES...
As of 242 PM EDT Saturday...
1. Strong to potentially severe thunderstorms and localized
flash flooding possible tomorrow.
2. A return to more seasonable temperatures and a brief break
in unsettled conditions is expected to start off next week.
3. Cooler with some showers next week and a larger storm system
Thursday.
&&
.DISCUSSION...
As of 242 PM EDT Saturday...
KEY MESSAGE 1: Behind our quiet weather today, shower chances will
increase near the International Border tonight into tomorrow morning
ahead of a strong cold front. There is a bit of lower confidence in
severe weather tomorrow, though the potential for some stronger
storms remains unchanged. A weaker shortwave will traverse just
north of the International Border beginning tonight with a slight
chance to chance PoPs near Massena as some showers may graze the
northern St. Lawrence Valley. Into the daytime, mixing will increase
into the late morning with a drying of the low levels across central
and southern Vermont. Into northern New York, proximity to the front
should keep mixing tempered with precipitation ongoing. The exact
depth of the mixing layer remains somewhat uncertain, with the HRRR
mixing nearly to 600mb, whereas the NAM3 mixes lower, closer to
850mb. A blend of the two seems reasonable, with a combination of
dry low level air, but increased mid level moisture advected north
from the Gulf. This results in a shallow inverted V type sounding
for the southern Champlain Valley and southern Vermont, with a
saturated mid level. While inverted V soundings usually indicate the
potential for isolated microbursts, the modeled DCAPE is around 700-
800J/kg, given the shallowness of the LCL. Furthermore, this DCAPE
will likely not be fully realized as overall instability will be
muddied with convective debris and moist mid layers, resulting in a
mid level inversion and little MLCAPE. This inversion will likely
help cap the vertical extend of many showers and embedded
thunderstorms. Regardless, there may be some synoptically driven
gusty winds tomorrow given stronger mixing around 30 to 35 MPH, with
top of the mixed layer winds around 50 kts. Additionally with the
inverted V profiles, stronger downdrafts may be possible with
embedded gusty winds under any thunderstorms. Have added gusty winds
to the forecast.
The more concerning aspect to the forecast will be widely
scattered to isolated hydro concerns. Guidance continues to
show good pwats across the region to 1.5 inches with several
CAMS denoting streaks of 3-6 hr QPF around 1-2 inches. Tall
skinny CAPE profiles with a deep warm cloud depth to around
10,000 ft are favorable for heavy precipitation. Have continued
with enhanced heavy rain wording tomorrow for localized flooding
concerns. The NAM3 and HRRR highlight the potential for three
rounds of showers with embedded thunderstorms, thus should an
area see some training cells, some localized flooding is
possible. The Weather Prediction Center has placed the entire
region in a Marginal Risk for Flooding potential tomorrow.
Current guidance points to the central Greens, and potentially
southern Vermont as areas we will continue to monitor for the
better chances for hydro concerns. Total rainfall tomorrow
ranges between near an inch in the St. Lawrence Valley to a
quarter inch in the Connecticut River Valley in Windsor County.
Rain will be persistent across the St. Lawrence Valley and more
showery elsewhere tomorrow. Rainfall amounts may be locally
higher under any thunderstorm activity.
KEY MESSAGE 2: Behind the cold front on Sunday, a much cooler air mass
will usher in a return to seasonable temperatures for Monday and
Tuesday. Highs will be near 70 to the mid 70s with overnight lows in
the upper 40s to mid 50s. These cooler temperatures however, will be
associated an upper trough and weak instability which could bring
some daily chances for showers, especially across the higher
terrain. These showers will be light in nature as they lack any
meaningful moisture or instability profiles. Best chances will be
Monday morning, particularly across the Adirondacks.
KEY MESSAGE 3: Large scale troughing will be established for much of
next week, bringing seasonably cool temperatures and several rounds
of shower chances as shortwaves pivot around the longwave. Diurnal
heating will help increase the shower chances in the afternoon a bit
due to the cool air aloft. However, most of the time it will be dry.
It is increasingly likely that a more organized area of low pressure
will move through Thursday into Thursday night, bringing widespread
rainfall. With the current favored track to the north, it will
likely bring gusty synoptic winds. A low level jet of 40 to 60 KTs
looks increasingly possible, as long as the low track continues to
be to the north. GEFS, EPS and CMCE combined ensemble probabilities
of more than an inch and two inches of total rain are 70-90 percent
and 20-50 percent respectively. The rounds of precipitation
currently look to be light enough and moving quick enough to prevent
much of a flooding threat.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
Through 00Z Monday...VFR conds expected through the forecast
period, except late in the period at KMSS. Mainly expecting
light winds less than 10 kts overnight with just some passing
scattered mid and high cloudiness, most prevalent across the SLV
and far northern counties. Decaying convection across the Ottawa
Valley may produce a dying light shower or brief sprinkle at
KMSS through 02Z, but low confidence suggests omission of this
possibilty at this point. LLWS also noted at KMSS and KSLK in
the 01-08Z time frame, generally 240/250 @ 35-40kt w/assoc.
modest turbulence. After 12Z, cold front begins to approach
from the northwest with increasing chance of showers and a few
stronger storms across northern counties, then progressively
south into central VT by early evening. Mixed signals in the
models on the strength of storms so confidence in widespread
storms is on the lower side of moderate, but be aware a
stronger line of convection is plausible in these areas from
noon/early afternoon onward into early evening with gusty winds
and turbulence. Winds generally south to southwesterly 08-12 kts
with gusts to 20 kts, though variable and erratic near any
convection.
Outlook...
Sunday Night: Mainly VFR, with local MVFR possible. Definite
SHRA, Slight chance TSRA.
Monday: VFR. Chance SHRA.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. NO SIG WX.
Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. Chance SHRA, Slight chance TSRA.
Wednesday Night: Mainly VFR, with local IFR possible. Chance
SHRA.
Thursday: Mainly MVFR, with areas VFR possible. Definite SHRA,
Slight chance TSRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
WHAT HAS CHANGED...Danzig
DISCUSSION...Myskowski/Danzig
AVIATION...JMG
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