Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
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FXUS61 KBTV 070956
Area Forecast Discussion
National Weather Service Burlington VT
456 AM EST Wed Dec 7 2016
A weak weather system is currently bringing a light snowfall to
the north country and will continue through the morning
commute. Accumulations will be light but will create slippery
driving conditions. Additional snow showers are in the forecast
for Thursday into Friday as colder air begins to moves in to the
region. Significant snow accumulations are possible in parts of
northern New York. The weekend is expected to be seasonably
cold with scattered snow showers each day.
.NEAR TERM /THROUGH TONIGHT/...
As of 400 AM EST Wednesday...Weak upper level trof causing
Light snow currently across the North Country. Have also noted
some observations in the Saint Lawrence valley showing light
rain where temperatures have warmed into the lower 30s. By 12z
most of this accumulating precipitation will have cleared our
CWA. There may be some lingering drizzle, though less
significant. Still anticipate development of low level southerly
jet, this will help temperatures to raise above freezing by mid
morning, already 32 at BTV. Today will remain cloudy and high
temperatures will reach the upper 30s to around 40.
Tonight our next weather system begins after midnight with some
lake effect snow in Northern New York off of Lake Ontario. Have
upgrade Lake Effect Snow Watch to an Advisory. Overnight
temperatures will be relatively mild with mins only in the 20s,
plenty of cloud cover. A strong upper level trof will push
through the Great Lakes region overnight. This feature does not
have as much synoptic forcing, but southwest flow will become
favorable for lake effect off Lake Ontario with cold air
advection. Flow will be strong enough for some snow to reach Jay
Peak area in Northern Vermont, some upslope enhancement as
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
As of 353 AM EST Wednesday...Lake Effect snow event will be
ongoing for Thursday and Thursday night. Aforementioned upper
level trof will push across Northern New York and New England.
Southern Saint Lawrence and Franklin Counties in the Adirondacks
as well as Jay Peak area in Northern Vermont will be main areas
to have accumulating snow with this Lake Effect snow set up
initially. With upper trof pushing through later Thursday the
rest of our forecast area will also have some light snow shower
activity except for the larger valleys. Snow showers will also
become a bit more convective, models continue to show some small
CAPE in the higher elevations. Going into Thursday night the
flow becomes less favorable for our forecast area and lake
effect band will drift South and out of our area. Most of our
forecast area will have just a dusting to an inch of snow. the
higher elevations of Vermont and Northern New York will have
2-4", and the highest summits from Mount Mansfield to Jay Peak
will see closer to 4-6" of snow. Have upgrade Lake Effect Snow
Watch to an Advisory. In the advisory area, snow totals will be
4-8" with some isolated higher amounts especially in extreme
Southern Saint Lawrence county.
.LONG TERM /FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --As of 455 AM EST Wednesday...The main stories during the long
term portion of the forecast will be some of the coldest
temperatures so far this season, with highs mainly in the 20s
and 30s. Also, increasing chances for wintry precipitation as
On Friday, the region will continue to be under cold advection
with a chance of snow showers and highs in the 20s.
On Saturday, a ridge of high pressure will build east from the
Great Lakes Saturday through early Sunday. The ridge of high
pressure will crest over the north country Sunday morning, and
then move off the coast Sunday afternoon. This will allow a warm
front to approach the region Sunday afternoon with increasing
cloudiness. Light snow will develop across the Saint Lawrence
valley and the Adirondacks in northern New York during Sunday
afternoon. This light snow will then spread east into Vermont by
late Sunday afternoon and early Sunday evening. Have raised
superblend pops to likely across the Adirondacks and Saint
Lawrence valley Sunday afternoon, with high chance pops (50
percent) across Vermont by late Sunday afternoon. Models showing
light snow across the region Sunday night, so have raised
superblend pops to likely for Sunday night.
On Monday, ECMWF and GFS models showing some differences, with
the GFS model having a surface low over the Gulf of Maine by 12Z
Monday. The ECMWF model has several waves of low pressure over
the Ohio valley at 12Z Monday. It looks like we will see some
rain or snow on Monday. Thus, have raised superblend pops to
high chance (50 percent) on Monday. Models continue to show some
differences for Monday night and Tuesday, so have stuck with
superblend pops, and will have a chance of snow showers in the
forecast for Monday night and Tuesday.
-- End Changed Discussion --
.AVIATION /10Z Wednesday THROUGH Sunday/...
Through 06Z Thursday...Light snow will overspread the TAF
locations from SW-NE between 06-09Z with developing IFR vsby
(1-2SM) and HIR TRRN OBSCD. Light snow accumulations (1-2")
anticipated over a period of 3-4 hrs...some impact expected to
airport ground ops for morning pushback due to light snow
Snow will start to break up into more showery conditions after
14z Wednesday, and temperatures will warm above freezing at all
TAF locations. Generally went with "VCSH" in the TAFs, but will
see lingering MVFR ceilings for most locations with HIR TRRN
OBSCD. South winds may gust 15-20kts in the Champlain Valley
after late morning thru afternoon/early evening.
Outlook 06Z Thursday through Sunday... Entire period - frequent
MVFR ceilings. Scattered snow showers each day, resulting in
localized IFR visibility and ceilings. Maybe extended period of
IFR for SLK Wednesday night into Thursday night with frequent
snow showers in vicinity of the nrn Adirondacks.
NY...Lake Effect Snow Advisory from midnight tonight to midnight
EST Thursday night for NYZ029.