Area Forecast Discussion
Issued by NWS Burlington, VT-- Remove Highlighting --
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FXUS61 KBTV 231754
Area Forecast Discussion
National Weather Service Burlington VT
154 PM 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/...
-- Changed Discussion --As of 134 PM EDT Sunday...At 1730Z, lingering light
flurries/sprinkles have generally ended across the Northeast
Kingdom. Strong low-level drying underway, and has allowed for
mostly clear skies to develop from the Champlain Valley wwd...and
also across s-central VT. Should gradually see some BINOVC develop
across n-central and nern VT next few hours. Afternoon highs
generally upr 40s to around 50 for the Champlain/St. Lawrence and
CT river valleys. Elsewhere, steep lapse rates (and clouds across
n-central/nern VT yielding colder readings in the low-mid 40s most
locations. Gradient flow will remain moderately strong through
sunset, as 980mb sfc low across ern Quebec slowly fills while
drifting ewd north of the St. Lawrence Valley tonight. Will keep
15-25mph with a few gusts to 35mph next 1-3 hrs, before gradually
diminishing with slow weakening of p-gradient and loss of steep
lapse rates as PBL cooling occurs toward sunset.
Generally quiet conditions tonight. A minor shortwave trough in
fast WNW flow 700-500mb layer will pass to our south across the
srn tier of NY and PA. This will yield some increase in mid-level
clouds, especially across the srn half of the forecast area. That
said, associated light pcpn should remain south of our area. West
winds continue 5-10 mph overnight, which will mitigate radiative
cooling and keep overnight lows mainly mid-upr 30s, except low 30s
in the 1-2kft elevational band.
Generally quiet weather expected Monday. Broad cyclonic flow
remains in place aloft, and it appears we`ll have another surge of
low-level CAA and possible passage of weak mid-level shortwave
trough. Shallow instability layer will produce clouds by afternoon
and possible light upslope precipitation into the Adirondacks and
nrn Green mtns. Freezing levels generally 2000-2500ft, so can`t
rule out some flurries down to about 1000ft in elevation Monday
aftn, especially wrn slopes. May see passing sprinkles in the
valley locations, and kept PoPs generally less than 20%. High
temps generally low-mid 40s, except upr 40s near Lake Champlain
and with downslope warning effects across ern Windsor county/VSF
area. Winds will be W-NW winds 8-15kts with gusts developing in
the afternoon with presence of steeper lapse rates.
-- End Changed Discussion --
.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. 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 /18Z Sunday THROUGH Friday/...
-- Changed Discussion --Through 18z Monday...Conditions have improved to VFR all TAF
locations with strong sfc low departing across ern Quebec north of
the St. Lawrence Seaway. Main issue will be continued gusty W-WNW
winds through 00Z, generally sustained 10-20kts with gusts to
25kts. Winds will diminish to 5-10kt after sunset. Minor upr
trough passing to our south will bring increasing mid-level clouds
overnight, though should remain VFR. Outside chance of MVFR at
KSLK 06-12Z Monday with upslope flow conditions, but kept current
TAF VFR. WNW winds generally 8-15kts after 14Z Monday.
Outlook 18z Monday through Friday...
18z Monday through 00z Wednesday: Broad upper trough in place
bringing variable cloudiness. Generally VFR ceilings, with
possible MVFR showers and higher elevation snow showers late
Monday afternoon through Tuesday vcnty of the nrn Mts. Increasing
chances for MVFR ceilings at MPV/SLK later Monday night through
Tuesday, with periods of light precipitation and MVFR cigs/vsby
00Z Wednesday through 00Z Saturday: Next low pressure system
approaching from the Great Lakes/Ohio Valley brings chances for
widespread showers and periods of MVFR conditions late Thursday
through the first half of Friday.
-- End Changed Discussion --
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