Area Forecast Discussion
Issued by NWS Burlington, VT-- Remove Highlighting --
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FXUS61 KBTV 221751
Area Forecast Discussion
National Weather Service Burlington VT
1251 PM EST Sun Jan 22 2017
Skies will remain cloudy over the north country for most of this
week, with a prolonged period of unsettled weather expected. A
low pressure area will develop along the mid Atlantic coast on
Monday and will move slowly northeast to around Cape Cod by
early Tuesday night. This low pressure area will bring mixed
precipitation types to the north country Monday night and
Tuesday, with rain, sleet, snow and freezing rain possible
Monday night and Tuesday. This low pressure area will then move
northeast into the Canadian maritimes by Wednesday morning.
Another low pressure area over the Great Lakes will move east
and bring a chance of rain and snow showers to the north country
from Wednesday through Saturday.
.NEAR TERM /THROUGH MONDAY/...
-- Changed Discussion --As of 1231 PM EST Sunday...Updated forecast to drop highs by
another 1 to 3 degrees with temps mainly holding in the mid to
upper 30s...a spot 40 is still possible near VSF.
Otherwise...low clouds and areas of drizzle/freezing drizzle
depending upon temp will continue for the rest of the afternoon.
Also...web cams still showing areas of fog...especially higher
terrain where snow pack is present. All covered well in current
Previous discussion from 427 AM EST Sunday...Models continue to
show plenty of low level moisture trapped beneath a low level
temperature inversion. Expect this to continue today through
Monday. Surface observations showing temperatures at or near the
dew point across the region at this time, resulting in quite a
bit of fog across the north country early this morning.
Expecting this fog to burn off by late this morning. Have gone
with slight chance pops for light rain or periods of drizzle
today. Temperatures will climb to the upper 30s to lower 40s
Tonight, models continue to hint at some colder air working into
the region today as winds shift to the north. Could see a slight
chance of some more drizzle or very light mixed precipitation
tonight. Have gone with colder min temperatures today, but still
a few degrees warmer than mos guidance, given expected cloud
On Monday, models continue to show upper ridge over the region,
with a ridge of surface high pressure over the Canadian
maritimes. This surface ridge will result in some cold air
east of the Green Mountains. ECMWF and GFS models continue
trend of slowing down the arrival of precipitation into the
region from the low pressure area along the mid Atlantic coast
until Monday night. Thus, have kept most of the day on Monday
dry, with just cloudy skies expected.
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.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 350 AM EST Sunday...High pressure retreating far to our
north and east and mild air over the North Country will set up
for complex thermal profiles as low pressure system approaches
from the DelMarVa coast Monday night. Precip north of the low
will spread from south to north accompanied by a tight pressure
gradient and strong easterly 850mb jet. As precip spreads across
the North Country, NAM and GFS BUFKIT soundings show warm layer
mainly between 800-700mb resulting in widespread wintry mix
into Tuesday morning. Models currently suggest sleet/snow mix
being the predominant PType for most of the area. With initial
surge of moisture expect most areas to see 1-4 inches of snow
sleet mix through Tuesday morning. As low continues to track
near the coast, reaching SE Long Island midday Tuesday PWATS
increase to around three quarters of an inch Monday night and
Tuesday. Associated 500mb trough becomes more negatively tilted
resulting in warmer air aloft moving into eastern VT and
transitioning precip to rain for the latter half of Tuesday. The
surface low continues NEwd toward the coast of Maine into
Tuesday night with colder air eventually moving into the North
Country and ending the precip at snow as it begins to taper off
Tuesday night into early Wednesday. Storm total snow/sleet
accumulations through 12Z Wednesday will generally range from 2
to 5 inches, with higher amounts possible depending on how long
the warm layer remains in place, how quickly the colder air
moves in as the surface low moves NE.
The strong 850mb jet Monday night into early Tuesday will lead
to downsloping winds, easterly slope enhanced precip and
westerly slope/valley shadowing. With steady precip and cloudy
skies, do not think low level jet will be able to fully mix
down, resulting in gusts of 20 to 30 mph in most valleys with
stronger gusts for south central Vermont of 30 to 40 mph and
higher at the summits of Vermont and northern NY.
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 350 AM EST Sunday...Lingering snow showers expected but
overall active period continues as we remain under 500mb
troughiness. Quick moving low forms in the lee of the Rockies
and arrives for the latter half of Wednesday with rain/snow
showers expected to be light. Low chances for rain/snow showers
continue into the weekend. Above normal temperatures close out
the work week with a cooling trend. Saturday temperatures strive
to be within 5 degrees of normal for late January.
.AVIATION /18Z Sunday THROUGH Friday/...
-- Changed Discussion --Through 18Z Monday...Aviation focus continues to be on low cigs
and associated ifr/lifr conditions at slk/rut/btv. Thinking mvfr
cigs will develop at btv by 20z...and 22z or so at rut...but
prevail most of the time at slk. Soundings at kmss show low
level moisture advecting back into the Saint Lawrence Valley
this evening so have lowered cigs back toward ifr conditions by
00z. Otherwise...used a persistent forecast overnight with cigs
ranging from vfr to ifr depending upon location. Not expecting
widespread fog...due to increasing 975mb to 925mb winds of 15 to
25 knots...especially after 06z.
Outlook 18Z Monday through Thursday...
Expecting a wintry mix of precip to develop on Monday evening
and continue into Tuesday with the potential for moderate icing
and major impacts to the aviation community. A mix of
snow...sleet...and freezing rain is expected...with the heaviest
precip occurring between 03z-15z Tuesday. Expect mvfr to ifr
cigs/vis with periods of lifr vis in the heavier bursts of
snow/sleet. Also...gusty southeast/east winds are likely at
Rutland during this time period...with areas of wind shear and
turbulence areawide associated with 925mb to 800mb winds of 50
to 60 knots. Improving conditions with lingering rain/snow
showers on Weds into Thursday.
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