000
FXUS61 KBTV 250604
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
204 AM EDT Mon Sep 25 2023

.SYNOPSIS...
We remain on the northern fringes of a post-tropical storm.
Meanwhile, the approach of a weak surface cold front bringing
high altitude wildfire smoke from the north will help hold the
storm to our south. Aside from isolated afternoon showers
tomorrow, high pressure will effectively build in through the
upcoming week. As a result, seasonable and dry weather will
prevail through the end of the week and possibly beyond.

&&

.NEAR TERM /THROUGH TUESDAY/...
As of 124 AM EDT Monday...Updated forecast to reflect current
satellite trends for fog and sky cover mainly. Also adjusted
temperatures to reflect current observations. Previous
discussion follows.

Previous Discussion... While no impactful weather is expected
through tomorrow night as temperatures remain seasonable and
little to no rain falls, there is quite a bit of interesting
meteorology going on across our region. The main items of
interest are wildfire smoke and patchy fog. There also is a
chance of light showers tomorrow afternoon associated with
lingering low level moisture and steepening low level lapse
rates, mainly in the southern half of Vermont and adjacent Essex
County, New York.

Two distinct ribbons of smoke are currently evident in both
satellite and webcam images and generally consistent with
modeling. The first one is currently over northern New York and
Vermont, which is mixing with high clouds still streaming
northward from post-tropical storm Ophelia. Air quality remains
moderate and not expected to degrade. Then more smoke is present
well to our north over central Quebec province and southeastern
Canada, on the cool side of a surface cold front helping spark
cloud streets in southern Quebec. This smoke will continue
moving southward behind the front and become situated over much
of our region tomorrow, likely producing a milky sky with
otherwise sunny conditions. As surface low pressure to our south
drifts eastward, our large-scale wind direction will remain
more easterly than northerly, which will support relatively
light winds in north/south valleys during the day while the St.
Lawrence Valley sees breezy conditions with gusts upwards of 25
MPH. This easterly flow will help the smoke drift westward
through the day and largely exiting our area overnight. As has
been the case in recent days and weeks, smoke is not expected to
cause respiratory issues with low concentrations near the
surface based on both upstream observations and modeling.

As for valley fog, we remain in peak climatological fog season
and with shortening days, any fog that develops tends to stick
around longer. At the same time, there is a lot of dry low level
air, which has mixed down in pockets with sharply lowering dew
points this afternoon. The southward push of strong Canadian
high pressure will help generate some increasing winds
aloft/higher terrain, as well, which will reduce radiation fog
potential even as skies largely clear. That being said, while
fog is not explicitly forecast at this time for the overnight
hours, it would not be surprising to see patchy dense fog in
sheltered locations, especially in central and eastern Vermont.
Tomorrow night may more of a traditional cool, clear night as
the surface high better asserts itself in our region, with more
typical fog development especially in northern New York.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
As of 250 PM EDT Sunday...Picture perfect fall weather will
persist through much of the week as high pressure settles
directly overhead. Abundant sunshine and near normal
temperatures can be expected each day. Nights will be on the
chilly side as we`ll have optimal radiational cooling; patchy
fog will also be possible in the favored valley locations.
Patchy frost may also be possible in the cold hollows of the
Adirondacks and Northeast Kingdom, so subsequent shifts will
need to monitor for the need of any headlines.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
As of 250 PM EDT Sunday...The ridge starts to break down as we
head into the weekend, though model guidance differs on details.
The GFS is the most robust in keeping the high overhead, while
the CMC and ECMWF indicate the ridge axis shifting eastward
while an upper trough swings into the Great Lakes. Both of the
latter models develop a surface low off the Mid Atlantic coast
over the weekend as the upper trough moves eastward, but still
keep the high entrenched over northern/eastern New England. All
in all, the weekend still looks dry as best chances for any
showers will remain well to our south. At worst, current
expectations are we`d see increased cloud cover, which would
help keep overnight temperatures closer to normal.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Through 06Z Tuesday...Tricky forecast with where we will have
fog overnight. Currently have a variety of categories with Fog
at MPV, MSS and EFK ranging from MVFR to LIFR. Expect fog to
remain until about 13 or 14z when it will lift and all sites
will then be VFR. Mid to high clouds continue across the
Adirondacks and south-central Vermont. Winds will continue to be
light and terrain driven through about 10z before north to east
winds increase. Beyond 13z, wind speeds pick up to 8 to 14
knots sustained with gusts 15 to 20 knots possible, particularly
at KMSS. Fair weather cumulus with bases 5000-7000 ft agl are
likely between 15z and 21z. After 22z, winds will begin to
subside, but remain around 4 to 8 knots. Fog formation will be
possible again Monday night.

Outlook...

Tuesday: VFR. NO SIG WX.
Tuesday Night: VFR. Patchy BR.
Wednesday: VFR. NO SIG WX.
Wednesday Night: VFR. NO SIG WX.
Thursday: VFR. NO SIG WX.
Thursday Night: VFR. NO SIG WX.
Friday: VFR. NO SIG WX.

&&

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

&&

$$
SYNOPSIS...Kutikoff
NEAR TERM...Haynes/Kutikoff/Neiles
SHORT TERM...Hastings
LONG TERM...Hastings
AVIATION...Neiles