325
FXUS61 KBTV 310514
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
114 AM EDT Sat Aug 31 2024
.SYNOPSIS...
Clouds will be increasing overnight with occasional rain
showers and a few rumbles of thunder developing on Saturday,
along with gusty south winds. The highest potential for showers
will be from around sunrise to early afternoon on Saturday with
temperatures mostly in the 70s and localized gusts up to 30 mph.
Warmer with additional showers are possible on Sunday afternoon,
before cooler and drier weather returns for most of next week.
&&
.NEAR TERM /THROUGH SUNDAY/...
As of 105 AM EDT Saturday...Winds continue to be the concern
with this latest update. Already seeing gusts of 30+ mph along
the northern slopes of the Adirondacks, and we`ve started
gusting to 20+ mph here at BTV. Meanwhile, Colchester Reef is
starting to approach 30 kt. Have bumped up wind gusts
accordingly. Clouds continue to spread over much of
central/western VT and northern NY. They`re a bit more extensive
than previously anticipated, so increased cloud cover, as well.
Otherwise, the forecast is on track and no other changes were
needed.
Previous Discussion...GOES-16 Visible Satl imagery conts to
show low level stratus deck acrs northern NY slowly pushing
eastward toward the CPV, while thinning at the same time.
Meanwhile, water vapor shows additional ribbon of mid lvl
moisture and associated elongated s/w energy over the central
Great Lakes moving toward our cwa. It wl be this pre-frontal
trof and associated moisture that wl produce showers with a few
embedded rumbles on Sat acrs our cwa. Timing of rain is
challenging on Saturday, especially CPV into VT, with deep dry
layer in place, along with developing gusty south/southwest flow
btwn 925-850mb, which may result in some shadowing. Have noted
bottom of the inversion is around 975mb with mix layer winds of
30-35 knots, so anticipating localized gusts 25 to 35 mph likely
in the CPV btwn 08z-16z Sat. Developing pres gradient and
increasing clouds overnight should limit fog development, maybe
a few patches in the NEK and CT River Valley. Temps mostly in
the lower 50s NEK to lower 60s CPV.
As clouds thicken and lower and scattered showers develop, this
should act to stabilize profiles and limit mixing for lighter winds
in the aftn hours. Sounding profiles show rather minimal instability
with mostly moist adiabatic profiles and CAPE of only a few hundred
J/kg at best. Given the lack of instability feel best potential for
a rumble or two is over northern NY into parts of the CPV, but
probability is <20% attm. SPC has continued to place northern NY in
marginal risk for severe for day2 outlook, but if trends continue
feel this could be removed in day1 outlook Did note ingredients for
localized heavy downpours, such as pw values btwn 1.70 and 1.90",
warm cloud depths of 11.5kft to 12.0kft and a period btwn 16z and
21z when the wind profiles and storm vectors support potential for
back building/training showers. However, given the lack of
significant forcing to maximize rainfall efficiency, feel the threat
for flooding is <5% on Saturday. WPC has our entire cwa in marginal
risk of rainfall exceeding flash flood guidance on Sat. A few heavy
downpours are possible within the heavier convective elements, but
impacts wl be minimal. Temps wl be slightly cooler on Saturday with
more clouds/showers than today with values mostly in the 70s, but
humid wl be higher.
The shower axis wl shift into central/eastern VT by 03z Sunday,
before exiting our cwa by 06z. South/southwest flow wl keep temps in
the 60s overnight with muggy conditions anticipated.
&&
.SHORT TERM /SUNDAY NIGHT/...
As of 254 PM EDT Friday...Sunday will start out with one cold front
continuing to push southeastward and away from our area, while
another approaches from the northwest. There won`t be too much of a
break or separation between the showers ending in the morning across
our eastern zones, then renewed chances for showers with embedded
thunderstorms pushing across our area during the afternoon. Winds
will be gusty, especially ahead of and along the front. Maximum
temperatures on Sunday will reach the upper 70s to lower 80s.
Temperatures will drop off pretty sharply behind departing cold
front, dipping into the 40s across much of the area Sunday night.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 254 PM EDT Friday...Large ridge of surface and upper level high
pressure will build into our region from Canada beginning on Monday,
bringing cooler and drier weather to our area. Temperatures will be
quite cool Monday night with good radiational cooling set up, lows
area wide should dip below 50. For the rest of the week have gone a
bit below guidance for overnight temperatures with Canadian high
pressure over the area. No significant weather through the week.
&&
.AVIATION /05Z SATURDAY THROUGH WEDNESDAY/...
Through 06Z Sunday...VFR conditions will generally prevail
through the first half of the TAF period, with the exception
being KSLK which is already reporting MVFR ceilings. Other than
this site, expect VFR conditions through about 13z, then
ceilings lower to MVFR from northwest to southeast through 18z,
then remaining BKN-OVC 1500-2500 through the remainder of the
TAF period thereafter. Scattered to numerous showers will spread
eastward with the lower ceilings, and visibility may be reduced
to 5SM at times in any heavier rain. An isolated thunderstorm is
also possible. Showers end after 00z Sun. South/southeast winds
of 8-12 kt will continue through much of the period, with gusts
to 25 kt possible at KBTV/KPBG, and to 20 kt elsewhere until
the onset of steadier showers.
Outlook...
Sunday: VFR. Chance SHRA, Slight chance TSRA.
Sunday Night: VFR. Chance SHRA.
Labor Day: VFR. NO SIG WX.
Monday Night: VFR. NO SIG WX.
Tuesday: VFR. NO SIG WX.
Tuesday Night: VFR. NO SIG WX.
Wednesday: VFR. NO SIG WX.
&&
.MARINE...
South winds of 10 to 15 knots this evening will become 20 to 30
knot after midnight with gusts up to 40 knots likely around
sunrise on Saturday. Waves 1 to 2 feet will build to 3 to 5
feet by Saturday morning.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Taber
NEAR TERM...Hastings/Taber
SHORT TERM...Neiles
LONG TERM...Neiles
AVIATION...Hastings/Myskowski
MARINE...Clay/Taber
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