596
FXUS61 KBTV 180513
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
113 AM EDT Fri Jul 18 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 SATURDAY/...
As of 710 PM EDT Thursday...The Severe Thunderstorm Watch is
over as the strongest line of thunderstorms is moving east of
the forecast area.
Previous discussion...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 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 /05Z FRIDAY THROUGH TUESDAY/...
Through 06z Saturday...A combination of MVFR/VFR cigs prevail
across our taf sites with intervals of IFR at SLK. Expect these
conditions to continue for the next couple of hours, before VFR
develops at all sites by 00z. West to northwest winds continue
at 5 to 10 knots with localized gusts up to 20 knots possible at
MPV/EFK and BTV thru this morning. High pres will result in VFR
conditions from 12z this morning through 06z Saturday with
decreasing wind speeds.
Outlook...
Saturday: VFR. NO SIG WX.
Saturday Night: Mainly VFR, with local MVFR possible. Likely
SHRA, Slight chance TSRA.
Sunday: Mainly VFR, with areas MVFR possible. Chance SHRA, Slight
chance TSRA.
Sunday Night: VFR. 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/Storm
SHORT TERM...Danzig
LONG TERM...Boyd
AVIATION...Taber
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