Area Forecast Discussion
Issued by NWS Burlington, VT-- Highlight Changed Discussion --
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FXUS61 KBTV 180449
Area Forecast Discussion
National Weather Service Burlington VT
1149 PM EST Tue Jan 17 2017
A weak area of low pressure will move northeast up the Saint
Lawrence valley overnight. A secondary low pressure area will
form south of Long Island late tonight and will move slowly
eastward south of New England on Wednesday. A mix of snow,
sleet, freezing rain and rain will be over the North Country
overnight through Wednesday. A ridge of high pressure will
slowly build into the north country on Thursday and will remain
over the region through this weekend.
.NEAR TERM /THROUGH WEDNESDAY NIGHT/...
As of 1040 PM EST Tuesday...No significant changes to the
forecast needed at this point with precipitation trends
progressing as expected. 700-500mb trough is elongating from the
srn Great Lakes ewd across NY, with embedded shortwave trough
crossing our forecast area over the next several hrs. Generally
seeing steady light precipitation across nrn NY in the form of
ZR/R/IP, with mainly snow across VT where thermal profiles are
just slightly colder. As of 03Z, have seen 1" of snow accumulation
at BTV. With primary surface low still holding together across
Lake Ontario and shortwave trough translating thru, it appears
we`ll have another 3-4 hrs of steady precipitation in most
sections, before becoming less organized/continuous toward
daybreak on Wednesday.
Snow/Sleet/ice amounts will be highly variable depending on
location. It appears 2-4" snowfall generally across the
Champlain Valley into n-central/nern VT, with 3-6" on the
eastern slopes of the Green Mtns, aided by 30-35kt 900-500mb
sely upslope flow thru 09z or so. Suspect highest accumulations
by morning will be along the ern slopes of the Greens Mtns from
Ludlow to Brookfield. In NY, getting mix of sleet, freezing
rain, and even plain rain briefly at SLK with a temperature of
33F at 03Z. Will see localized icing of several hundreths of an
inch. Snow/sleet generally an inch or so for Franklin/St.
Lawrence counties, but locally 1-3" on the ern slopes of the
Adirondacks into the Plattsburgh area.
Bottom line: Despite modest accumulations, slick travel is
expected overnight and for the morning commute on Wednesday with
snow covered roadways. Definitely allow extra time if you plan
to travel overnight thru Wednesday AM.
Expecting precipitation to wind down Wednesday morning, with
some light rain or snow possible Wednesday afternoon. Have
lowered pops to slight chance for Wednesday night for some light
rain or snow showers possible.
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
As of 316 PM EST Tuesday...Generally improving conditions as
500mb shortwave exits east and ridge begins to build in over the
North Country. Lingering light showers focused over the high
terrain will diminish Thursday and Thursday night. Cooler air
will accompany high pressure with 925mb temperatures remaining
in the negative single digits to single digits above 0C. As the
500mb ridge crests over the region, gradually clearing skies
will result in min temperatures in the 20s to low 30s throughout
the period. Max temperatures will generally range from the mid
30s to low 40s Thursday and Friday.
.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 316 PM EST Tuesday...A shortwave will attempt to move
into the 500mb ridge and produce a slight chance for
precipitation but reinforcing ridge at the surface and limited
moisture will likely lead to some clouds but not much precip
Saturday into Saturday night.
More significant system will develop a closed surface low
Sunday night around the Ohio River Valley with large southern
stream 500mb low. Moisture feeding from Carolina coast will
bring PWATs around 1 inch into the North Country as negatively
tilted 500mb trough moves NEwd. This will result in warm air
aloft and possible mixed precip moving into the North Country
from south to north late Monday. Models differ on track of
primary surface low, affecting how much warm air moves into the
region. But GFS and ECMWF agree on strong low level jet of
50-65kts late Monday through Tuesday.
.AVIATION /06Z Wednesday THROUGH Sunday/...
-- Changed Discussion --Through 00Z Thursday...MVFR/IFR/LIFR conditions at all stations
currently as wintry mix moves into the area in the form of
snow/sleet as well as some freezing rain for New York stations.
Conditions will improve slightly when precipitation begins to
taper off after 15Z but ceilings will remain borderline
MVFR/VFR until the end of the period.
Winds will be southerly at 5-10 knots for most of the area with
KRUT seeing some gusts around 20 knots. KMSS will be the lone
exception as northeasterly flow stays locked in though most of the
period with winds 05-15 knots.
00Z Thursday through 00Z Friday...VFR with brief MVFR/IFR
00Z Friday through 00Z Monday...VFR, as a ridge of high pressure
will be over the region.
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VT...Winter Weather Advisory until 1 PM EST Wednesday for
NY...Winter Weather Advisory until 7 AM EST Wednesday for NYZ029-
Winter Weather Advisory until 1 PM EST Wednesday for NYZ028-