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Area forecast discussion 
National Weather Service Burlington Vermont
955 am EDT sun Oct 23 2016

strong low pressure system will depart across the St. Lawrence
seaway today, bringing an end to rain and snow showers late this
morning. Some lingering snow showers over the higher terrain
of northern into northeastern Vermont could persist into this
afternoon. Variably cloudy and seasonably cool conditions will
prevail Monday through Wednesday. Another wave of low pressure
approaching from the Great Lakes and Ohio Valley will bring the
next chance for rain, generally later Thursday into Friday.


Near term /through Monday/...
as of 950 am EDT Sunday...deep low pressure 979mb north of Quebec
city, que. Still yielding strong westerly gradient flow across the
north country. Will continue to see seasonably cool/breezy/gusty
conditions, generally 15-25mph with gusts to 35mph thru mid aftn,
aided by steep low-level lapse rates and good low-level mixing. In
terms of precipitation, rain/snow has ended in most locations, but
still getting some 15-25dbz across far nrn Vermont. Sfc obs include 34f
in light snow showers at efk/cda, so will keep chance snow/rain
showers across N-central into nern Vermont next few hours. Highest
summits could see an addition coating to an inch thru 17-18z.

Previous discussion...closed low continues to meander about the
St Lawrence Delta in Quebec with base of trough having pushed east
of VT, bringing an end to precip west of The Greens. Strong gusty
winds will remain over the region today with clearing skies,
especially in downsloping/leeward valleys. Expect isolated power
outages with gusts up to 40mph possible.

Cold air continues in the northwest flow with 925mb temperatures only
maxing out at 3c-4c this afternoon. Even with some partial
clearing, expect high temps generally in the 40s (near 50f at
btv). Gradient flow diminishes this evening. Some clouds increase
from the SW this evening into tonight with lows generally 35-40f,
but locally near freezing in the nrn Adirondacks.

Generally quiet weather expected Monday with a slight chance for
some upslope snow showers as a mid-level shortwave embedded in the
flow moves just to our south. Temperatures generally in the mid
30s to upper 40s. West-northwest winds 8-15kts with gusts developing in the


Short term /Monday night through Tuesday night/...
as of 411 am EDT Sunday...the north country will remain under
cyclonic flow from the departing surface low pressure area over
eastern Canada through the period. Expecting mainly upslope rain
and snow showers over the Adirondacks and Green Mountains through
the period. Have gone with slight chance pops through the period
to account for this. Have kept the Champlain and Saint Lawrence
valleys dry through the period.


Long term /Wednesday through Saturday/...
as of 411 am EDT Sunday...on Wednesday, one more day of upslope
rain and snow showers across the Adirondacks and Green Mountains,
as the region remains under cyclonic flow. High pressure area to
build east from the Great Lakes Wednesday night, so expecting fair
and dry weather Wednesday night into Thursday morning. European model (ecmwf) and
GFS models in good agreement in showing rain showers moving into
the region late Thursday afternoon ahead of a warm front. Rain and
snow showers will continue across the region Thursday night and
Friday. An upper trough will move through the region on Saturday,
so will continue with chance pops for rain and snow showers.


Aviation /14z Sunday through Thursday/...
through 12z Monday...VFR/MVFR conditions this morning improving
to VFR throughout the late morning and persisting throughout the
taf period. Gusty west to northwest winds will prevail through
much of the period...however after 15z the winds will be strongest
with gusts in the 25 to 35 knot range, before tapering off to
around 10kts or less this evening into the overnight.

Outlook 12z Monday through Thursday...

12z Monday through 00z wednesday: generally VFR with possible MVFR
in upslope showers Monday.

00z Wednesday through 00z friday: IFR/MVFR fog development
possible during the early morning hours.


as of 435 am EDT Sunday...Lake Wind Advisory continues for Lake

Strong west to northwest winds of 20 to 30 knots continue across
Lake Champlain today. This will result in wave heights of 3 to 5
feet. The highest waves will be along Eastern Shores exposed to a
greater fetch on west winds; specifically those locations adjacent
to the open waters north of the Charlotte Ferry and south of
Valcour Island.


Btv watches/warnings/advisories...
New York...none.


near term...banacos/kgm
short term...wgh
long term...wgh

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