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Area forecast discussion 
National Weather Service Burlington Vermont
311 PM EST Sat Jan 31 2015

high pressure will bring drier and much colder air to the north
country, ending any lingering snow showers this morning. Low
pressure will pass south of New England on Monday, bringing a
chance for snow. Another low pressure system will bring additional
chance for snow mid-week. Temperatures of 10 to 15 degrees below
normal will persist into the middle of next week.


Near term /until 7 PM this evening/...
as of 1255 PM EST Saturday...wind chill warnings and advisories
have been cancelled...with wind chill readings now generally above
associated criteria.

A cold winter day featuring ineffective sunshine as highs this
afternoon only reach zero to +10f in most locations. Low-level
northwesterly downsloping into the CT River Valley will allow for a few
readings into the lower teens this afternoon from White River jct to
Springfield. Sea-level pressure gradient remains moderately strong
between departing low pressure south of Nova Scotia and high
pressure building east from southeastern Ontario and western New York. While
we'll see clear/dry conditions areawide today...N-NW winds of
10-15 miles per hour will contribute to afternoon wind chills in the 10 to 20
below range (and lower at Summit level). Surface ridge axis builds
overhead by early this evening...and this will allow winds to
gradually subside this afternoon and will see nearly calm
conditions by around/just after sunset. Stratus layer associated
with upstream northern stream shortwave trough will begin to advect eastward
into our northern New York counties late in the afternoon into the evening
hours. Have shown this increasing cloud trend while keeping
conditions mainly clear through 7pm across Vermont.


Short term /7 PM this evening through Monday night/...
as of 348 am EST the surface ridge shrinks
southward tonight, an upper level wave will bring slight to low
chance for snow showers mainly across the higher terrain and
western slopes as we stay in northwest flow. Clouds accompany the
upper level wave and overnight temperatures will moderate with
minimums ranging from negative low teens in the Northeast Kingdom
to low single digits above zero in southern Vermont.

The wave looks to wash out by Sunday morning, so potential for
precipitation will be confined to tonight. Behind this wave, a
reinforcing shot of cold air will keep temperatures 10 to 15
degrees below normal. Expect Sunday maxes to be in the single
numbers north and teens south.

Zonal flow aloft across the northeast will bring an upper level
trough to the Great Lakes region Sunday night...with a
strengthening surface low moving up to Ohio River valley. This low
will increase clouds and the potential for snow reaching southern
zones early Sunday morning. Models trending more northern reach of
precipitation shield as the low pressure center moves over the 40n
70w benchmark on Monday. Therefore have increased probability of precipitation with chance
reaching the international border and likely into central Vermont
and Adirondacks. Would like to see model runs show consistency on
this solution before confidence can increase in potential for snow
reaching advisory criteria. Precipitable waters show levels just shy of this
past storm, but drier air and persistent drying northerly flow
could keep precipitation aloft...ending as virga for at least the
beginning of this system or northern half of the forecast area.

Temperatures continues to be frigid Sunday night with mins
ranging from -20f to -2f and Monday only reaching -5f to single
digits above zero.


Long term /Tuesday through Saturday/...
as of 310 PM EST Saturday...surface high pressure will provide
the northern New York and Vermont area with dry cold weather for
Tuesday. A weak low passes to our north Tuesday night bringing our
first chance for snow showers in the extended portion of the
forecast. On Wednesday a stronger low crosses the area...slowly
moving northeast of the area late Wednesday night into early
Thursday morning. This will be our best chance for some light snow
showers. High pressure will once again ridge into the area from
Thursday through Friday. Another weak low passes north of the
north country Friday night into Saturday bringing the next chance
for snow showers. Extended forecast will generally be active with
several weak lows bringing light snow showers to the area...and
cold with below normal temperatures. The only day with a chance of
some near normal temperatures is Wednesday when low will be
crossing the area.


Aviation /20z Saturday through Thursday/...
through 18z Sunday...mainly VFR conditions expected through the
period as a ridge of high pressure builds east from the Great
Lakes. A weak trough of low pressure will move through the area
overnight...mainly after 06z Sunday with just a slight chance for
some snow showers and some VFR broken ceilings. Conditions clear up
after 12z.

Outlook 18z Sunday through Wednesday...

18z Sunday-12z Monday...VFR.

12z Monday-00z Tuesday...mainly VFR as system slides south of
region. Could see some light snow across southern Vermont from 12z
Monday through 00z Tuesday as low pressure area passes south of
New England.

00z Tuesday-12z Wednesday...VFR.

12z Wednesday-12z Thursday...some MVFR in snow showers with
clipper crossing the area.

12z Thursday-Friday...VFR.


Btv watches/warnings/advisories...
Vermont...Winter Storm Watch from late Sunday night through Monday
evening for vtz008>012-018-019.
New York...Winter Storm Watch from late Sunday night through Monday
evening for nyz034-035.


near term...banacos
short term...kgm
long term...neiles

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