803
FXUS61 KBTV 290204
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
1004 PM EDT Wed Aug 28 2024
.SYNOPSIS...
High pressure over the region will bring seasonably cool and dry
conditions through the end of the work week. Temperatures will warm
through the weekend, with several rounds of showers expected, before
cooler and drier conditions return early next week.
&&
.NEAR TERM /THROUGH FRIDAY/...
As of 1000 PM EDT Wednesday...SLK already down to 48F with
mostly clear skies and light winds under a shallow llvl
inversion. Have lowered temps in deeper valleys of the Dacks by
several degrees, while continuing partly cloudy skies thru
midnight. Lows generally near 40F SLK to mid 50s near Lake
Champlain. Sfc high pres is centered just south of Hudson Bay,
which will continue to advect drier air on low level winds of 10
to 15 knots, which should limit fog production acrs the dacks
overnight. Still thinking slightly less winds and some localized
patchy fog is possible over central/eastern VT valleys toward
sunrise. We will continue to monitor winds and clouds for
potential mention of fog at SLK with next update, otherwise rest
of fcst in good shape.
Previous discussion below:
A fall-like afternoon can be seen across most of the region in
the wake of the cold front, with temperatures generally in the
60s to low 70s for most locations. Overnight lows will also be
on the cool side under mostly clear skies, with temperatures
dropping onto the 40s and low 50s. With upper level ridging
moving overhead and surface high pressure, winds will be light
and terrain driven overnight, fog development may be possible
overnight, especially across eastern Vermont and places that saw
rainfall earlier this morning.
The cooler and dry weather will continue for Thursday, with high
temperatures in the upper 60s to mid 70s along with partly to mostly
sunny skies. Heading into Thursday night, there looks to be some
increasing moisture to our south, which looks to bring some
increasing cloud cover to northern New York. Temperatures overnight
Thursday will be a few degrees warmer, but still in the upper 40s
and 50s.
&&
.SHORT TERM /FRIDAY NIGHT/...
As of 335 PM EDT Wednesday...Friday will observe an upper low sliding
east and 500mb ridging building in its place. Although surface high
pressure will be shifting east, it`s going to be slow to break down
again an incoming surface trough. Pressure gradients will tighten as
a result, resulting in a breezy, but not too unpleasant day. South
winds will pick up to 10 mph with gusts to 20, locally up to 25 in
the Champlain Valley. Outside of increasing clouds as the upper
ridge crests midday, skies should be fairly clear. So temperatures
should easily climb into the mid 70s, perhaps up to 80 in spots
across the broader Champlain and St. Lawrence Valley. Friday night
will be warm, as increasing moisture and warm advection maintain low
temperatures in the mid 50s to mid 60s, with the warmest conditions
in the St. Lawrence Valley. Precipitation may start to eke into the
region during the pre-dawn hours, but the bulk of any activity will
be on Saturday.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 335 PM EDT Wednesday...For Saturday, a rather strong prefrontal
trough will translate east. Although instability is not too strong,
with about 250-350 J/kg of elevated CAPE, the upper jet
configuration will be favorable along a favorable axis of low-level
confluence. Combined with 1.75", or even locally higher PWATs, this
should result in showers and a rumble or two of thunder across the
region. Clouds and rain should keep daytime highs cooler in the low
to mid 70s, but it will be somewhat more humid. Better moisture and
decreasing instability Saturday night will allow precipitation to
shift east along the trough axis. After a brief break Sunday
morning, the actual cold front arrives Sunday afternoon and evening.
Although the front will not have as much rich moisture, the vort
associated with the large upper trough is vigorous while the upper
jet remains somewhat favorably aligned. With the sharp thermal
gradient coming in behind this system, there should be a broken to
complete line of showers and an embedded rumble of thunder. Between
Saturday and Sunday`s rain, about half to three quarter inches of
rain is expected, and basins should be able to handle that. Dry
conditions and partial clearing ahead of the strong incoming front
will allow a brief, but quick warm up into the mid 70s to lower 80s
Sunday afternoon. This will all come crashing down overnight. It`ll
take some time for the bulk of the coldest air to settle overhead,
but temperatures mainly in the 50s Sunday night will then struggle
to warm above 70 on Monday and perhaps Tuesday as well. Any
lingering showers Monday morning should quickly dissipate as the
upper trough continues east. Following this, ensemble guidance is
still supportive of a solid period of dry weather.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Through 00Z Friday...Predominantly VFR conditions throughout the
24 hour TAF period with high pressure taking control. Small
chance of some valley fog overnight, mainly between 09Z and
12Z, however enough winds just off the surface to prevent fog
from becoming widespread or dense. Have kept fog/mist out of
most TAF sites, with the exception of KMPV where some 3SM BR is
included 09Z-12Z. Winds at the surface will generally be light
and terrain driven.
Outlook...
Thursday Night: VFR. NO SIG WX.
Friday: VFR. NO SIG WX.
Friday Night: VFR. Chance SHRA.
Saturday: Mainly VFR, with areas MVFR possible. Likely SHRA,
Slight chance TSRA.
Saturday Night: Mainly MVFR, with local IFR possible. Likely
SHRA, Slight chance TSRA.
Sunday: Mainly VFR, with local IFR possible. Slight chance SHRA.
Sunday Night: Mainly VFR, with local MVFR possible. Chance SHRA.
Labor Day: VFR. Slight chance SHRA.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.
&&
$$
SYNOPSIS...Kremer
NEAR TERM...Kremer/Taber
SHORT TERM...Haynes
LONG TERM...Haynes
AVIATION...Duell
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