425
FXUS61 KBTV 221427
AFDBTV

Area Forecast Discussion
National Weather Service Burlington VT
927 AM EST Fri Nov 22 2024

.SYNOPSIS...
A brief break in precipitation is expected today before more
elevationally dependent snow and rain spreads back through much
of the region. This time, greater precipitation amounts will be
focused over central and eastern Vermont, where light snow
accumulations are expected primarily tomorrow morning. Then
a breezy, upslope pattern will develop, supporting several
inches of snow through the weekend in the northern Green
Mountains.

&&

.NEAR TERM /THROUGH SATURDAY/...
As of 921 AM EST Friday...Minimal changes needed to the forecast
this morning, with just a some light showers across portions of
the forecast area as a dry slot continues to work into the
region. Winds have been becoming more easterly through the
morning, with southeasterly winds expected towards the early
afternoon. Only a few changes to temperatures and sky cover
were made, with the forecast remaining on track.

Previous Discussion...
So far the first storm of two in quick succession is playing
out pretty well, including localized sloppy snow of up to a
couple inches in southern/western portions of the Adirondacks.
Early this morning we are seeing additional bands of light
precipitation (less than 0.1" per hour) spiraling in from the
east and pushing northward through the North Country. These
showers seem to be on the nose of a low level jet maximum, and
with a break in any precipitation, it will help bring in
periodic gustier winds early this morning, primarily near and
just west of the southern Greens. Expect the showers will
eventually provide the Northeast Kingdom with some measurable
precipitation finally this morning. By this afternoon, a
pronounced dry slot evident on water vapor channels of GOES-16
satellite imagery currently over southern New England will move
across our region, shutting off steady precipitation until
tonight. Clouds will scatter effectively with breezy easterly
winds, such that large periods of the day will be sunny and mild
with temperatures reaching near 50 in the warmest spots.

The latest HREF shows potential for some heavier snowfall rates
(liquid of greater than 0.1" per hour) over portions of
southern and eastern Vermont late tonight/early tomorrow
morning associated with another low pressure system deepening to
our southeast. There is substantial spread in precipitation
amounts amongst model guidance, however, especially in southern
and western portions of Vermont. Greatest confidence in snowfall
during this period is ironically in northeastern Vermont where
they have largely missed out on precipitation so far during this
long duration event. Northwesterly flow in the low levels while
being more underneath the upper level low should provide good
large scale and orographic lift while rich moisture circulates
back to the west of a deepening low pressure system passing well
to our east. As such, frontogenetic forcing will be much
greater east of Vermont where precipitation amounts will be
higher. Still, we`re looking at a swath of 0.2" to 0.35" roughly
near and north of I-89 from the western slopes eastward during
the overnight hours into tomorrow morning. Snow ratios will be
as low as 5-8:1 with near freezing temperatures close to the
ground and above freezing surface temperatures for most
locations. That will translate to a coating to a couple inches
of greasy snow at most, and the accumulations look
elevationally dependent snow across this region through tomorrow
morning.

While widespread precipitation will wrap up during the morning,
northwesterly upslope snow showers and valley rain showers will
become the main story across northern Vermont as relative
humidity remains high up to 700 millibars under stiff northwest
flow. Have boosted wind gusts quite a bit from the previous
forecast as uniform winds aloft should help transport winds
efficiently. Top of the mixed layer winds will be near 40 MPH
across much of Vermont, representing potential peak gusts.
Temperatures will be notably cooler than today, mainly in the
30s with some low 40s in the wide valleys.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/...
As of 324 AM EST Friday...Saturday night into Sunday looks favorable
for upslope snow. An upper vort will dive across the region as it
gets absorbed in the broader upper low pulling away from the region.
A jet streak will strength up to 120 knots aiding in upper
divergence. A few forecast soundings suggests some dubious moisture
in the DGZ, but there appears to at least be enough across our
northern mountains to produce some modest upslope snow showers.
Global model output of about 0.2-0.4" over the northern mountains
suggest we should eke out an additional 2-5" above 2000 feet. Lower
elevations may see a mix of snow early Sunday morning, but gradual
warming from the mid 30s to 40s should make this pretty short-lived
with minimal impacts. It will be breezy Sunday with 10 to 15 mph
winds and gusts 20 to 25 mph likely. It still looks possible for a
few gusts of 30 to 35 mph are possible on eastern slopes of the
southern Greens and Adirondacks. The final vort max embedded in the
gyre of the upper low departs late Sunday afternoon, and
precipitation will start to more quickly taper off.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
As of 324 AM EST Friday...Northwest flow will start off the extended
as ridging settles in briefly. Cold advection will result in a night
of mid 20s to lower 30s to start the new work week on only upper 30s
to mid 40s during the day. Our weather pattern will be a little more
active than recent weeks. Another upper trough will race east Monday
night into Tuesday. Southwesterly flow will prevent much cooling
overnight. Precipitation will begin to reach the area during the
pre-dawn hours Tuesday. The main thing to watch will be the exact
arrival time in parts of the Northeast Kingdom, where temperatures
will be below freezing Tuesday morning. If it makes it before too
much heating can occur, there could be some light freezing rain.
However, if it`s too late, then conditions will be able to warm
above freezing. Trends have been for a stronger surface low compared
to yesterday. This would support a slower arrival time of
precipitation, but also suggests we might be able to get a little
more liquid out of this, and we`ll happily take what we can get to
make up recent deficits.  Behind the system, there will be a
combination of mountain snow showers and a little lake effect snow
as well heading into Wednesday. Of course, the primary concern will
be how a fast moving area of low pressure progresses across the Ohio
River Valley and Mid- Atlantic region. An examination of
probabilistic bricks suggest the potential there could be some snow
on Thanksgiving Day, but the majority of individual ensembles
suggest next Friday or Saturday may be a bit more likely to observe
anything. There are also a few that have entirely nothing. So
there`s still plenty of uncertainty, as is natural for a Day 7-8
forecast. We`ll watch trends closely.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
Through 12Z Saturday...A slight improving trend to ceilings has
been observed over the past six hours, with primarily VFR
ceilings at this hour aside from MSS (MVFR) and SLK (IFR).
ceilings ranging from 800 feet at SLK to 4200 feet at PBG.
Steady, light rain, or a mix of rain and snow at SLK, is not
affecting visibilities, and precipitation areawide will taper
off through 16Z, resulting in scattering of low ceilings as a
mid-level dry slot moves in from the southeast. Late in the
period, especially after 06Z, additional precipitation will be
more likely to cause visibilities to fall with more MVFR to
locally IFR conditions developing. A mix of rain and snow is
especially probable at MPV and EFK, and possibly at RUT and BTV,
from 08Z to 12Z.

Winds have been trending stronger and more northeasterly early
this morning, although PBG and BTV remain northerly at this hour.
With the gusts developing this morning and expanding across all
sites, LLWS should diminish through 18Z. Confidence in stronger
gusts has increased for this afternoon with winds trending
southeasterly, as gusts at most sites reach 25-30 knots at
times, then taper off after 00Z. Finally, winds will increase
again as they trend northerly towards the end of the TAF period.


Outlook...

Saturday: Mainly MVFR, with areas IFR possible. Likely SN, Chance
RA.
Saturday Night: Mainly MVFR, with local VFR possible. Scattered
SHRA, Scattered SHSN.
Sunday: Mainly VFR, with areas MVFR possible. Scattered SHRA,
Scattered SHSN.
Sunday Night: Mainly VFR, with local MVFR possible. NO SIG WX.
Monday: VFR. NO SIG WX.
Monday Night: VFR. Likely SHRA, Chance RA, Chance FZRA.
Tuesday: Mainly MVFR, with local VFR possible. Likely SHRA.

&&

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

&&

$$
SYNOPSIS...Kutikoff
NEAR TERM...Kremer/Kutikoff
SHORT TERM...Haynes
LONG TERM...Haynes
AVIATION...Kutikoff