112
FXUS61 KBTV 171824
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
224 PM EDT Thu Jul 17 2025
.SYNOPSIS...
Scattered showers and thunderstorms, some strong to severe, will
move through today into the evening. Following, a strong cold
front will move through overnight and finally put an end to the
heat and humidity for the weekend. Cool and dry conditions will
prevail for most of the weekend, with a brief period of
unsettled weather Saturday night into Sunday morning, before
returning to cool conditions for next week.
&&
.NEAR TERM /THROUGH FRIDAY NIGHT/...
As of 200 PM EDT Thursday...Scattered showers and some thunderstorms
have begun to bubble up across the area, with some containing
frequent lightning. Some of these cells may have damaging winds, a
brief weak tornado or 2 and localized heavy rains over the course of
the afternoon/evening. As a result the Storm Prediction Center
has issued a Severe Thunderstorm Watch for Clinton County New
York, and all of central and northern Vermont. A prefrontal
trough has moved into the area based on the latest satellite
images and radar reflectivity axis across St. Lawrence County
New York. This will be the main focus for any potential severe
weather heading into the remainder of the afternoon. With
current temperatures running a few degrees above forecast, where
showers have not impacted observation stations, current
thermodynamic profiles indicate 1000-1500 J/kg of SBCAPE across
northern New York with pockets of 2000 J/kg just north of the
border. Furthermore, dewpoints are generally near 70 with Pwats
around 2" which is ample moisture and energy for cell
development today. The good news, is that unlike recent events,
these cells are moving so the flash flooding threat is low.
Dynamically speaking, the low responsible will be close to the
international border which will help effective shear to increase
toward 30-40 kts as the nose of a strong low-level jet enters
the region. These high shear values are currently across eastern
Ontario where the cold front resides. Lastly, surface- levels
in the hodographs suggest the potential for a weak brief tornado
or two with SRH around 150-200 m^2/s^2 by this afternoon. Cells
will likely start off in a multi-cellular cluster and then
continue into upscale growth by this evening to more of a broken
squall- line. A few discrete supercells out ahead of this line
cannot be ruled out which would be the best chance of any
tornado potential. From a broad view, the ingredients for severe
weather are present, however, there remains the question of
whether they will interact in tangent still. If the shear and
instability can align themselves any cells that develop have an
easy path to becoming strong to severe. This is in line with the
current SPC Slight Risk Outlook for severe storms across
northeastern New York and north/central Vermont. The main
threats for today will be damaging winds, and localized heavy
rain. Best timing for any severe storms across Vermont will be
between 5-8 PM.
The front looks to pass through beyond 8-10 PM tonight with strong
winds remaining overnight. Winds at 925mb will be around 40-50kts
which should mix down to the surface, particularly in the Champlain
Valley for gusts up to 30 kts. With the strong front, northwest
winds will usher noticeably cooler air and much lower humidity
values. Dewpoints this evening will be in the lower 70s, but by
Friday morning they will fall to the upper 40s to low 50s.
Temperatures will also take a dive from the upper 80s to the mid 70s
for highs tomorrow. Friday will be a spectacular day with calming
winds, seasonable temperatures, and clearing skies. Overnight relief
will also be present Friday night with good raditional cooling
looking to take place. Lows Friday night across the higher terrain
could drop into the low to mid 40s with mid 50s across the valley
floors.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
As of 200 PM EDT Thursday...Saturday looks to maintain the trend set
on Friday with seasonable weather for much of the day. Temperatures
will be in the upper 70s to low 80s with dewpoints near 60. Clear
skies in the morning will transition to increasing clouds throughout
the day as a broad shortwave approaches from the west. While there
is a general chance for showers Saturday afternoon into the evening,
trends have been pushing the shortwave axis further to the south out
of the region. Broad energy may lead to an isolated shower late
Saturday afternoon however most of the activity should remain in
southern Vermont and the lower Adirondacks. Given the timing of the
system as well primarily Saturday evening and overnight, the threat
of any strong to severe thunderstorms looks low attm. Overnight lows
on Saturday will remain seasonable in the upper 50s to low 60s.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 200 PM EDT Thursday...Showers will be departing Sunday with
some lingering chances mainly in northeastern Vermont before drier
conditions return by late Sunday. The replacement airmass will be
out of the Canadian plains and is strongly favored to be drier given
its continental origin. As such, pleasant conditions, highs in the
70s/low 80s through Tuesday, are anticipated with a slow warming
trend as the high`s center tracks slowly eastward and becomes
absorbed by the semi-permanent Bermuda Ridge over the western
Atlantic. Mid-late week, southwesterly flow is more likely to
return possibly resulting in a sharper warming trend back above
seasonal averages becoming more favored. Ensembles and blended
guidance favor a flattening of the upper level pattern which could
allow for a few showers or a thunderstorm to for over the North
Country by Wednesday/Thursday. Cloud cover and showers may be at
odds with projected highs which are projected back into the upper
80s/around 90, but these details will be teased out as we get
closer.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Through 18z Friday...Widely scattered showers will become more
numerous this afternoon with increasing chances of
thunderstorms through 00Z as a trough sweeps west to east
across the North Country. Some storms will be strong to severe.
Cloud layers will be lower than "usual" given LCLs below 3Kft
and higher likelihood of heavier rain elements. IFR is plausible
in showers/storms today and VLIFR possible should a storm pass
directly over a terminal. LLjet strength could product a few
areas of LLWS, but best shot of that lies at SLK; otherwise,
deep mixing will promote southerly gusts 20-30kts through 00z,
becoming westerly/northwesterly overnight and decreasing in
general. Most terminals will stand a good chance of MVFR CIGs
overnight before skies begin to clear in earnest after 12Z
Friday.
Outlook...
Friday Night: VFR. NO SIG WX.
Saturday: VFR. Slight chance SHRA.
Saturday Night: Mainly VFR, with local MVFR possible. Chance
SHRA, Slight chance TSRA.
Sunday: Mainly VFR, with areas MVFR possible. Slight chance SHRA,
Slight chance TSRA.
Sunday Night: Mainly VFR, with local MVFR possible. NO SIG WX.
Monday: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. NO SIG WX.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Danzig
NEAR TERM...Danzig
SHORT TERM...Danzig
LONG TERM...Boyd
AVIATION...Boyd
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