141
FXUS61 KBTV 170229
AFDBTV
Area Forecast Discussion
National Weather Service Burlington VT
929 PM EST Mon Dec 16 2024
.SYNOPSIS...
A warm front will produce a period of light rain showers overnight
with a few patches of freezing drizzle possible this evening across
eastern Vermont. Gusty southwest winds of 30 to 50 mph develop over
the northern Adirondacks and northern Champlain Valley tonight and
becoming westerly on Tuesday. A few power outages are possible.
Temperatures warm overnight into the upper 30s to upper 40s by
Tuesday, before cooler air arrives for midweek. A period of light
snow is likely on Wednesday night, followed by much cooler air by
the upcoming weekend.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
As of 925 PM EST Monday...A wind advisory continues for
northern/eastern Adirondacks, northern Champlain Valley, and east
side of the northern Green Mountains in VT from 7 PM this evening
until 4 PM Tues for localized gusts 45 to 50 mph.
Low level moisture is moving into the region on southeast flow
and areas of drizzle are developing. Drizzle is falling in many
areas in most of Vermont east of the Greens. It is also falling
in the southern Adirondacks and it will push farther northward
into New York`s North Country as well. Some areas east of the
Greens and in the Adirondacks are below freezing, so this
drizzle is likely freezing on some untreated surfaces.
Temperatures will hold steady for the next couple hours before
rising above freezing everywhere later in the night. Overall,
the forecast was in good shape and few edits were made.
Previous Forecast...Water vapor shows potent s/w energy and
associated axis of enhanced mid lvl moisture quickly approaching
the eastern Great Lakes, while a well defined dry slot is
moving into the central Great Lakes. Meanwhile, sfc analysis
places warm frnt feature over the Ohio Valley, while high pres
off the ne conus coast is helping to advect low level
moisture/clouds back into central/eastern VT this aftn. This
moisture combined with sfc temps hovering near 0C, may produce a
few areas of patchy drizzle/freezing drizzle this evening over
central/eastern VT thru 11 PM, which may require a SPS. Temps
eventually warm above freezing as heavier precip arrives aft
midnight.
As sfc boundary moves toward our fa, the pres gradient sharpens
associated with 1036mb high pres off the ne conus coast, which
results in quickly increasing 925mb to 850mb wind fields. Guidance
conts to show 850mb winds of 55 to 65 knots, while 925mb winds are
55 to 60 knots acrs the northern downslopes of the Dacks and small
portion of the northern CPV tonight around 06z. Given this signal,
combined with HREF prob of sfc wind gusts >45 mph at 80 to 100% wind
advisory conts overnight into Tues. However, I have to admit,
sounding profiles show rather limited mixing overnight and would
support localized gusts in the 30 to 40 mph range. For Tuesday as
cooling aloft develops and bl warms into the 40s to near 50F, sfc to
850mb lapse rates steepen and mixing of stronger winds toward the
sfc improves, supporting localized gusts 45 to 50 mph eastern Dacks
and east side of the northern Greens in VT, especially given the
sharp inversion height near summit level. Elsewhere, breezy
conditions prevail with gusts 25 to 40 mph likely acrs most of our
cwa. Even with modest cold air advection aloft on Tues, temps should
warm into the mid 40s to near 50F most locations, including eastern
VT.
Rainfall is unimpressive with this system as strong downsloping
winds wl produce a qpf shadow here in the CPV. Furthermore, a
quickly developing dry slot wl result in precip ending by 12z Tues.
Generally thinking a tenth to quarter inch acrs the region with
slightly less western CPV to localized higher amounts High Peaks and
parts of the southern Greens. The lack of deep layer moisture and
weak lake induced instability limits additional precip/qpf on Tues
acrs our fa.
Tuesday night is quiet with just a few lingering flurries in the
mtns as temps fall back into the mid 20s mtns to mid 30s CPV.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/...
As of 352 PM EST Monday...A seasonal start to Wednesday quickly turns
dreary as a frontal system moves through the area Wednesday night
and Thursday morning. Slightly above average temperatures are
expected Wednesday with highs in the upper 30s to lower 40s as cloud
cover and southerly winds keep cooler air at bay. By Wednesday
night, precipitation chances increase as a quick moving upper-level
low sweeps across the region. Thermal profiles initially favor rain
for central and southern VT valleys as surface temperatures are
above freezing Wednesday afternoon. Although we expect rain
initially, we expect all to see a switch to snow Wednesday
overnight. Snow ratios to start will be relatively low in the realm
of 3-5:1 in southern VT and closer to 8-10:1 in central and northern
VT which could limit snow totals. However, in the higher elevations
where cooling will take place much faster, higher snow amounts will
be possible. While near advisory level, we are expecting 3-5" below
1500 ft with summits seeing between 6-10".
Most of the precipitation will clear by Thursday morning with a
decent chance for some upslope snow showers on the western Green and
Adirondack Mountains Thursday morning and afternoon as winds
transition to the northwest. A few locations could see an additional
1-3" from this upslope flow. Lake effect activity looks unlikely
given the lack of moisture available. While instability, and
southwesterly wind direction look conducive, weak surface and
mid- level moisture would limit any lake effect activity.
Thursday evening will be rather quiet before another quick
moving weak system rolls in Friday.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
As of 352 PM EST Monday...The end of the week looks rather quiet with
a brief chance for some snow showers Friday and Saturday. A weak
clipper system will track out of the Great Lakes Friday morning, but
will have a hard time accomplishing any meaningful precipitation as
it runs into drier air and a coastal low off the New England coast.
The clipper gradually decays Saturday morning overhead of the area
leaving some snow showers and much cooler air behind it for the
remainder of the weekend. High temperatures dip back into the single
digits in the Green and Adirondack mountains and low-to-mid-teens in
the Champlain and St. Lawrence Valleys as high pressure builds in.
Low temperatures in the single digits Saturday and Sunday nights
were nudged towards the NBM25th-percentile as models seemingly
underestimate the cool air drainage from Canada under northerly
winds.
High pressure builds in behind the clipper continuing the cooling
trend Sunday afternoon through Monday. Clear and dry conditions look
to begin next week.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
Through 18Z Tuesday...The next 24 hours will be challenging with
changeable conditions in the world of aviation. Winds are
blowing southeasterly to southwesterly this evening 5-10 knots
except in MSS where a northeasterly wind dominates instead.
Winds will be increasing over the next 6 hours with gusts 20-35
knots expected out of the south/southeast. Winds are anticipated
to remain gusty as they shift out of the southwest by around
12Z-18Z Tuesday. Gusts are forecast to gradually decrease
following this time period but may remain elevated 15-30 knots
through the 24 hour TAF period. LLWS is forecast for all sites
throughout the next 24 hours. Most likely time period for wind
shear will be now through about 15Z-20Z Tuesday.
As most precipitation is expected to fall in the form of
drizzle or rain, visibilities will, for the most part, be 4+
miles (MVFR or higher). One likely exception will be SLK as we
have rain changing over to snow there about 14Z-22Z Tuesday.
This may result in lower visibilities than anticipated. Ceilings
are a mixed bag this evening but anticipated to lower
throughout the night. MPV is already at 800-900 feet above
ground level cigs, and we are expecting it to stay down for much
of the next 6 to 10 hours. SLK is another spot that could
potentially have some IFR ceilings at times. A period of IFR
cigs is also possible this evening at PBG associated with
southeast flow off Lake Champlain, but confidence on this is not
high. Otherwise, all sites have 1500+ feet AGL cigs forecast
through the next 24 hours. Sites may see improvement in these
ceiling conditions 15Z-21Z and onwards as a dry slot fills in
quickly behind the precipitation.
Outlook...
Tuesday Night: Mainly VFR, with local MVFR possible. NO SIG WX.
Wednesday: Mainly VFR, with areas MVFR possible. Chance RA,
Chance SN.
Wednesday Night: Mainly IFR, with areas MVFR possible. Definite
SN, Definite RA.
Thursday: Mainly MVFR, with areas VFR possible. Slight chance SN.
Thursday Night: Mainly VFR, with local MVFR possible. Slight
chance SHSN.
Friday: Mainly VFR, with local MVFR possible. Chance SHSN.
Friday Night: Mainly MVFR, with local VFR possible. Chance SHSN.
Saturday: Mainly VFR, with areas MVFR possible. Chance SHSN.
&&
.MARINE...
South winds have increased to the 30 to 40 knot range this
evening. Localized gusts of 40 to 45 knots are possible after
midnight. Winds shift to the west on Tuesday morning and
decrease to 15 to 25 knots. Waves 1 to 3 feet will build 3 to 6
feet tonight and slowly subside on Tuesday as winds shift to
the west.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...Wind Advisory until 4 PM EST Tuesday for VTZ001>003-016.
NY...Wind Advisory until 4 PM EST Tuesday for NYZ027-028-030-031-
034.
&&
$$
SYNOPSIS...Taber
NEAR TERM...Myskowski/Taber
SHORT TERM...Danzig
LONG TERM...Danzig
AVIATION...Storm
MARINE...Team BTV
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