Area Forecast Discussion
Issued by NWS Burlington, VT-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KBTV 260232
Area Forecast Discussion
National Weather Service Burlington VT
1032 PM EDT Sat Mar 25 2017
High pressure continues to build southward out of Canada this
afternoon. A clear and cold night is expected overnight, with
low temperatures widely varying from the single digits to the
upper teens above zero. Unsettled and warmer weather returns for
Sunday and Monday as developing low pressure over the central
U.S. pushes the front back north Sunday afternoon into Monday,
with periods of rain, snow and mixed precipitation expected
through mid-week. A winter weather advisory has been raised for
light freezing rain.
.NEAR TERM /UNTIL 8 AM SUNDAY MORNING/...
-- Changed Discussion --As of 1031 PM EDT Saturday...No changes needed to current
forecast. Surface high pres with clear skies and light winds
will allow temperatures to cool to near 0F SLK/NEK to mid teens
Challenging low temp forecast tonight as 1037mb high pres
located over southern Hudson Bay builds into the North Country.
This has resulted in rapidly clearing skies this evening with
northwest winds at 5 to 10 knots and modest low level cold air
advection. Expecting a sharp low level thermal inversion to
develop in the deeper/protected valleys allowing for winds to
decouple and temps to quickly fall...especially NEK/SLK. Have
noted 18z MAVSLK is now -1F...so based on this info and very
deep dry layer with ideal cooling conditions...with fresh snow
pack...have cut temps across the dacks/nek back to around 0f.
Elsewhere...some northeast winds at mss may keep temps up in the
mid teens slv and in the cpv. Sharp thermal inversion will
result in the coldest air temps in the deepest protected valleys
with midslopes/summits holding in the mid/upper teens.
Otherwise...captured latest clearing trends and placed into sky
grids and made some adjustments to the dewpts. Rest of forecast
in good shape.
Previous discussion below:
As high pressure continues to ridge into the North Country out
of Canada this afternoon and evening skies will clear from North
to South. Clear skies, light winds and the late season cold
snowpack overnight will bring about another cold overnight
period, generally single digits and teens. Some high clouds will
try to advance from the southwest towards early morning. The
overnight period will be dry.
-- End Changed Discussion --
.SHORT TERM /8 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
As of 318 PM EDT Saturday....More active weather returns for the
short term portion of the forecast. Have raised a winter weather
advisory for Western Essex County NY, and from the spine of the
Greens Eastward for light ice accumulations. On Sunday
precipitation will begin from the southwest and spread across
our forecast area during the afternoon hours. Precipitation
should hold off till after 18z and by that time temperatures
should be warm enough across most of the region to just expect
rain at that point. Temperatures should warm pretty quickly with
some morning sun across our northern zones and warm air
advection all day as low pressure system lifts Northward into
Great Lakes region. Maximum temperatures will reach the lower
40s across almost the entire north country. The only exception
will be Western Essex county NY where there will be a threat for
some freezing rain. Have gone warmer than most MOS guidance for
Sunday night due to clouds and precipitation, as well as warm
air advection across the region, but still looks cold enough
especially east of the Greens to cause some icing issues. Sunday
night low pressure system continues to push eastward towards our
area, with more precipitation expected. Have some categorical
pops mentioned overnight and then continuing into Monday with a
front lifting across our area. Warmer air aloft moves gradually
eastward over the top of the shallow layer of colder air,
bringing with it the threat for mixed precipitation especially
east of the Greens. Colder air is tough to scour out there. It
does not take very much icing to impact travel. By about 15z
Monday warm air advection should be strong enough to have our
entire area raise about freezing with lower to mid 40s for
afternoon high temperatures. The low pressure system will be
very slow to push east of our region, and think there will still
be some showers around on Monday night, but temperatures should
remain warm enough to preclude any further issues. Mixed
precipitation always presents a complicated forecast.
.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 359 PM EDT Saturday...A cold front will approach the
region on Tuesday, with mainly rain showers expected, so have
gone with mainly likely pops. Expecting rain showers to continue
into Tuesday night, before changing to snow showers late
Tuesday night, mainly over the higher elevations of the
Adirondacks and Green Mountains. A chance of rain and snow
showers will continue into Wednesday. A ridge of high pressure
will build into the region on Thursday and Friday, with fair and
dry weather expected.
ECMWF and GFS models showing differences for Friday night and
Saturday, with the GFS model having a high pressure area over
the region with fair and dry weather. The ECMWF model brings a
low pressure area up through the Great Lakes Friday night and
Saturday, so have stuck with the superblend pops and will have
a chance of rain and snow showers for Friday night and Saturday.
Given model differences for Friday night and Saturday,
forecaster confidence is low at this time.
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
Through 00Z Monday...Low clouds continue to erode around the north
country this evening, with most IFR/MVFR ceilings scattering out
right now. Skies will continue to clear out overnight as a
ridge of high pressure builds southeast from Canada overnight.
VFR conditions will remain over the region until very late as
MVFR ceilings and precipitation begins to move in from the
southwest after 20Z.
Outlook 00Z Monday through Thursday...
00Z Monday through 00Z Thursday...periods of mixed
precipitation, though mainly rain with cigs/vsby variable from
IFR to MVFR. Moderately gusty NW winds likely Wednesday.
00Z Thursday through 00Z Friday...Mainly VFR, except for some
scattered snow showers over the Adirondacks and Green Mountains.
VT...Winter Weather Advisory from 7 PM Sunday to 11 AM EDT Monday
NY...Winter Weather Advisory from 2 PM Sunday to 11 AM EDT Monday