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Area forecast discussion 
National Weather Service Burlington Vermont
1236 PM EST sun Dec 28 2014

Synopsis...
a cold front will move across the area this morning, bringing
gusty winds and light rain showers for the first half of the day.
Drier and colder air will filter in behind the cold front,
starting a colder trend for the work week. A reinforcing shot of
colder air will follow a weak surface trough on Monday, resulting
in maximum temperatures staying in the teens and 20s this week.

&&

Near term /until 7 PM this evening/...
as of 1235 PM EST Sunday...all of the precipitation has moved out of the
area now...though some clouds still remain. Back edge of cloud
shield still moving into the Saint Lawrence valley. No significant
changes for 1230 update. Previous discussion follows.

Back edge of precipitation shield has moved through the Saint
Lawrence valley, ending rain showers there. Expect the back edge
to continue to swiftly move across the Adirondacks and Champlain
Valley before 14z, and exit southeastern Vermont shortly after
15z. Radar VAD wind profiles show winds decreasing, so expect
gusts to diminish in the middle morning hours.

Mild temperatures, gusty winds and light rain showers across the
north country this morning as a result of being in the warm sector
of a surface low pressure system that is traversing northeastward
across Quebec. The associated cold front with this system is
currently moving across the western St Lawrence Valley as of
1140z. Expect the front to cause south to southwesterly winds to
shift to the west across the area by mid-day. Cooler air will
filter in behind the front...causing temperatures to generally
fall throughout the day. Therefore the maximum temperature will occur
in the morning, with temperatures dropping to the m20s-m30s around
5pm. Low level clouds remain behind the front, with not much
chance for full sunshine today, though some breaks/clearing are
expected in the afternoon to evening hours.

Gusty winds will also subside behind the front, as winds shift
from south to west and low level jet exits eastward in the late
morning.

&&

Short term /7 PM this evening through 6 PM Monday/...
as of 343 am EST Sunday...behind the front, drying west to
northwest flow continues, allowing for dissipating clouds. Low
temperatures Sunday night/Monday morning will fall into the teens
and middle 20s.

On Monday, a weak surface trough will move through the north
country from north-northwest to SSE, increasing cloud cover and possibly
producing a few snow showers mainly across the higher terrain on
northwest facing slopes. Models show weakening deformation as the
trough moves over the north country, and washing out late Monday
afternoon. Do not expect much accumulation with this feature.
However, there will be a reinforcing shot of colder air behind it,
with persistent north to northwest flow. Monday maximum temperatures
will range from the teens to low 30s, while Monday night will be
noticeably colder in the negative single digits at the summits to
low teens in the valleys of south central Vermont.

&&

Long term /Monday night through Saturday/...
as of 343 am EST Sunday...cold air advection develops Monday
night as a large area of high pressure spreads into the region
from the west and northwest. This will result in colder and drier
conditions with lows Monday night getting down into the single
digits above and below zero. The below normal temperatures
continue on Tuesday with highs in the middle teens to middle 20s...which
is generally 10 to 15 degrees below normal. Dry weather will
continue on Tuesday. Little change is expected on Wednesday with
below normal temperatures continuing and maybe a little bit of
lake effect snow across parts of northern New York. Otherwise...a
pattern change will take place on Thursday as an upper level
trough of low pressure moves into eastern Canada and brings a
chance of snow showers to much of the area through Thursday night.
An even more noticeable change comes late Friday into Saturday as
southwest flow aloft develops and brings warmer air into the
region. In addition...a large upper level trough of low pressure
will approach the region on Saturday. Ultimately a surface low
pressure system will track to our northwest which puts US in the
warm sector. Based on this scenario...looking like snow at the
start of the event and then change to rain or a rain/snow mix most
areas.

&&

Aviation /18z Sunday through Friday/...
through 18z Monday...sct/bkn mainly VFR ceilings expected over the
next 24 hours as high pressure builds into the region with modest
west/northwesterly surface winds from 5-12 kts...occnly gusty.
Exception at kslk where MVFR ceilings will generally prevail. Weak
energy embedded within the upper flow may spark a few flurries at
kslk/kmss in the 06-12z time frame...but generally dry weather is
expected.

Outlook 18z Monday through Friday...

18z Monday Onward...mainly VFR through the period. Exception at
kslk where westerly flow off Lake Ontario will allow scattered -shsn and
occasional MVFR/IFR conditions to prevail.

&&

Marine...
as of 340 am EST Sunday...a lake Wind Advisory remains in effect
this morning as south winds continue at 15 to 25 knots, resulting
in waves heights of 1 to 3 feet...with some higher swells
possible. A surface cold front is approaching Lake Champlain from
the west, keeping the pressure gradient tight along with
channeling up the valley producing winds around 25 knots between
09z and 15z. When the front passes over the lake this morning,
winds will shift to the west/northwest and slowly weaken as high
pressure builds into the region.

&&

Btv watches/warnings/advisories...
Vermont...none.
New York...none.

&&

$$
Synopsis...kgm
near term...kgm/neiles
short term...kgm
long term...evenson
aviation...jmg
marine...kgm

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