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827
FXUS61 KBTV 221401
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
1001 AM EDT Sun Sep 22 2024

.SYNOPSIS...
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Much of the region will remain dry, outside of some localized
light precipitation chances across St. Lawrence County. The
gradual cooling trend will continue during the next several
days, bringing high temperatures from the upper 60s to mid 70s
down into the lower 60s to near 70. More widespread
precipitation chances are still expected beginning Tuesday
evening and continuing into Wednesday and Thursday.
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&&

.NEAR TERM /THROUGH MONDAY/...
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As of 951 AM EDT Sunday...Despite a mix of low and mid-level
cloudiness across much of Vermont - a result of maritime
moisture that has advected into eastern sections of the forecast
area - sfc high pressure anchored across NH/ME/New Brunswick
will remain the controlling weather feature today. A few
sprinkles earlier this morning across far nern VT continue to
dissipate, and skies should trend partly sunny across VT and
mostly sunny across nrn NY. Will see a temperature gradient from
east to west across VT and northern NY this afternoon. The
warmest temperatures (upper 70s) are expected across the St.
Lawrence Valley, with generally low-mid 70s elsewhere across the
region, and a few upper 60s across far ern VT. Winds will
continue light S-SE at 5-10 mph today around the ridge of high
pressure. Slightly higher winds (10-15kts) expected across the
broad waters of Lake Champlain.

For tonight, the recent fog pattern should come to a temporary
close. Increasing winds at 700-1500 ft agl and incoming clouds from
the west should limit fog. Still, think some sheltered sections of
far eastern Vermont may not be exempt from fog, though. Overnight
lows will be warmest west where high clouds will start to shift into
northern New, and the Champlain Valley due to light south flow
likely remaining overnight with 50s. In cool hollows of the
Adirondacks and the rest of Vermont, generally 40s are
expected.

About dawn on Monday, higher theta e air will edge east with return
flow trying to establish itself after being absent so many days, but
high pressure will also build southwards. Precipitation should
develop along the St. Lawrence River, but will likely dissipate as
the center of persistent surface high pressure approaches northern
Maine. Easterly flow will advect dry air that will undercut moisture
trying to advance. We could see some virga continue to propagate
east, but any rain at the surface will likely stop at the
Adirondacks. The high clouds from the weak shortwave shifting east
and the reinforced east to southeast flow will help us stay cooler
with mid 60s to near 70.
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&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 312 AM EDT Sunday...Dry weather will continue to prevail
through much of the short term period with high pressure keeping
hold over the region. The ridge axis finally starts to shift
eastward Tuesday night, allowing precipitation to make some headway
into northern NY late. With rain to arrive later than previously
anticipated, we`re now expecting fewer clouds Monday night and
Tuesday, which will impact temperatures. More optimal radiational
cooling Monday night will make for another cool night with lows in
the mid 40s to low 50s. Meanwhile, have been bumped up Tuesday`s
highs a few degrees since we`re expecting more sunshine. Highs will
remain seasonable, in the mid 60s to around 70F. Tuesday night`s
lows will be similar to Monday night, though this will depend on how
quickly clouds arrive ahead of our next system.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 312 AM EDT Sunday...In general, the second half of the week is
looking unsettled, though there are still a lot of differences in
model solutions. Precipitation chances will increase on Wednesday
into Thursday as a northern stream upper trough digs into the Great
Lakes and pivots eastward. The uncertainty comes thereafter with how
this interacts and/or phases with a southern stream system over the
Southern Plains/Lower Mississippi Valley. And a potential tropical
system lifting toward the Gulf Coast by the end of the week only
further complicates matters. Note that the latest GFS phases the
northern and southern stream troughs, tapping into the tropical
moisture from the Gulf system, resulting in widespread rainfall
across our region with multiple inches of rain. This is an outlier,
however, and given the persistent pattern we`ve been in, favor
something more like the ECMWF and CMC which keep northern and
southern systems separate and shunts any tropical moisture well to
our south. Given the range of solutions, stayed close to the NBM for
this period.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
Through 12Z Monday...Conditions are currently VFR, though there
are some clouds near KSLK, KMPV, and KEFK that are just above
3000 ft agl. With solar heating, think ceilings should trend
gradually higher than descending. Winds are currently light and
variable, and should trend 6 to 10 knots between 14z and 22z
before returning close to 5 knots after 22z. Wind direction will
be mainly southeast, though northeast at KMSS. Winds abate some
after 00z, but are not expected to become calm. Additionally,
winds around 700-1500 ft agl should increase to 20 knots after
00z, and this should preclude fog in addition to increasing high
clouds moving in from the west.

Outlook...

Monday: VFR. Slight chance SHRA.
Monday Night: VFR. Slight chance SHRA.
Tuesday: VFR. Slight chance SHRA.
Tuesday Night: VFR. Slight chance SHRA.
Wednesday: Mainly VFR, with areas MVFR possible. Chance SHRA.
Wednesday Night: Mainly MVFR, with local IFR possible. Likely
SHRA.
Thursday: Mainly MVFR, with areas IFR possible. Chance SHRA.

&&

.BTV WATCHES/WARNINGS/ADVISORIES...
VT...None.
NY...None.

&&

$$
SYNOPSIS...Haynes
NEAR TERM...Banacos/Haynes
SHORT TERM...Hastings
LONG TERM...Hastings
AVIATION...Haynes