658
FXUS61 KBTV 221800
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
200 PM EDT Sun Sep 22 2024

.SYNOPSIS...
Stationary high pressure across New England will remain in
place through Tuesday. An approaching frontal system from the
Great Lakes region will spread mid and upper level clouds across
the North Country tonight into Monday. While there is a chance
for light rain showers on Monday across the St. Lawrence Valley,
the frontal system will generally weaken as it encounters the
area of high pressure across our region. A stronger upper level
low will finally bring a wetting rain to the region Wednesday
into Thursday. Temperatures will slowly trend downward over the
next several days, but generally remain above average for late
September.

&&

.NEAR TERM /THROUGH MONDAY/...
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.

&&

.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 SUNDAY/...
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 /18Z SUNDAY THROUGH FRIDAY/...
Through 18Z Monday...Generally VFR conditions expected through
the period. Prevailing BKN stratus deck across VT generally
3-5kft, so may see occasional MVFR conditions at MPV/EFK through
early this evening. The stratus will generally dissipate
thereafter, with a trend toward SCT-BKN150-250 from west to east
late tonight and into the daylight hours on Monday. Locally at
KMSS, may see BKN-OVC070-080 Monday morning with 20-30% chance
for some light -RW activity. Winds generally S-SE through the
period, except locally NE 5-9kts at KMSS through 04Z Monday. Locally
gusty winds to 20kts at KPBG this afternoon and possibly again
15-18Z Monday. Not expecting much in the way of nocturnal fog
at the TAF locations tonight. In addition to increasing mid-
upper clouds overnight, winds in the 700-1500 ft agl layer
should increase to 20 knots after 00z, and occasional mixing
should help limit fog formation except for the deeper river
valleys of far ern VT.

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