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Area forecast discussion 
National Weather Service Albany New York
issued by National Weather Service Burlington Vermont
1235 PM EST Wednesday Feb 10 2016

Synopsis...
an upper level trough will pass across the region today...bringing
scattered to numerous snow showers. Some lake effect snow showers
and squalls will remain possible through Thursday...along with
colder temperatures. Bitterly cold temperatures and wind chills
will follow in the wake of an Arctic frontal passage late Friday
into the weekend.

&&

Near term /until 6 PM this Evening/...
Lake effect Snow Advisory in effect from noon EST today until 6
PM EST Thursday evening for Herkimer and Hamilton counties...

As of 1232 PM EST...minor update to account for latest
observational trends. Scattered snow showers continue across the
Mohawk Valley, as well as elevated terrain areas early this
afternoon. Light accumulations remain possible this afternoon with
these snow showers...mainly across the higher elevations
(additional 1-2" possible across Herkimer and Hamilton counties
through 23z). High temperatures generally middle-upper 30s for the Hudson
Valley...and upper 20s to lower 30s elsewhere. Light S-SW winds
will gradually become light west toward evening.

Previous discussion...a double barrel area of low pressure will
track across northern New York and into northern New England as a
coastal low passes well south and east of Cape Cod. At the same
time a large upper level trough will dig into the eastern Great
Lakes region. This will result in several bands of mainly light
snow to move across much of the forecast area this morning. Once the surface
low passes by there will be a trough of low pressure extending
back across northern New York into the Great Lakes. This feature
combined with cyclonic flow and colder air funneling across the
relatively warm waters of Lake Ontario will set the stage for some
lake effect snow starting this afternoon. Herkimer and Hamilton
counties can generally expect 1 to 4 inches of accumulation by
late today. Highs today are generally expected to remain slightly
above normal ranging from the middle to upper 20s northwest to the
upper 30s southeast.

&&

Short term /6 PM this evening through Friday Night/...
Lake effect Snow Advisory in effect from noon EST Wednesday-6 PM EST
Thursday for Herkimer/Hamilton cos...

For tonight and Thursday...a cold cyclonic flow will remain across
the forecast area with a lake effect snowband expected to stretch across northern
Herkimer and Hamilton counties this evening and then settle
southward into central/southern Herkimer County...and SW Hamilton
County late tonight into Thursday. Total snowfall accums by late
Thursday in the advisory area should range from 4-8 inches over a 36+
hour period...with the greatest amts across central Herkimer
County. Elsewhere...some scattered snow showers will remain
possible Wednesday nt into Thursday across the central/eastern Mohawk
Valley...capital region...Schoharie valley and Berkshires. In
these areas...additional coatings of a dusting to 2 inches
are possible. Expect lows tonight to be in the mainly in the teens
except 5 to 10 above across the western Adirondacks. Highs on
Thursday are expected to be in the teens to middle 20s...except for
some single digits across the western Adirondacks.

Thursday night through Friday...the lake effect snow should
become multiband and shift to our west as the low level flow veers
Thursday nt. Then on Friday...winds will be backing in advance of an
approaching Arctic front. So...snow showers will increase once
again from northwest to southeast late Friday. It will already be cold...with Thursday
nt/Friday am mins falling into the single digits above zero for most
areas...except zero to 5 below across the Adirondacks. Wind chill
values could approach advisory levels in portions of the
Adirondacks toward daybreak Friday. Then on Friday...expect maximum temperatures to
reach the 20s for most lower elevations...and teens across higher
terrain...coldest across the western Adirondacks.

Friday night is expected to be very cold as Arctic air funnels
across the forecast area. Temperatures are expected to drop to 15 below zero to 15
above zero with wind chills zero to 25 below zero. Thus wind chill
advisorys may be needed.

&&

Long term /Saturday through Tuesday/...
in the wake of an Arctic boundary...the coldest air of the winter
season will pour into upstate New York and western New England on
Saturday...as a piece of the polar vortex swings across New York and
New England. The core of this feature will move directly over the
region...allowing for a period of brutally cold air to impact the
region. In fact...850 hpa temperatures are shown by several models to
drop to -30 to -35 degrees c. These temperatures could be record cold
levels for 850 hpa temperatures at Albany...as the coldest 850 hpa temperature
measured at kaly is -30 c on a few past occasions.

Temperatures on Saturday will be steady/falling the entire Day. Valley
areas will see highs in the morning near 10...and fall through the
single digits...with high terrain areas below zero through much of
the day. In addition...gusty west-northwest winds of 10 to 20 kts will make
for very cold wind chills levels. It should be dry...however...with
no precipitation expected...and a mix of sun and clouds.

For Sat night...the main story will be the bitter cold temperatures and
dangerously cold wind chills. Lows temperatures will fall to -5 to
-15 degrees in valley areas...and -10 to -20 over the high terrain.
These temperatures are impressive considering there will be gusty winds all
night...and some areas have little snow pack in place. Along with
the gusty winds...wind chill values will be as low as -20 to -30
degrees in valley areas and -30 to -50 in the higher elevations.
Wind chill warnings will likely be needed for much of the area...and
will continue to highlight this danger in the severe weather potential statement statement.

Temperatures will rise on Sunday to the single digits for highs in most
areas...along with a good deal of sunshine. Although it won't be
quite as windy...there will still be a breeze...and wind chill
values will still be rather low. Winds may finally start to diminish
on Sunday night....as surface high pressure build into the area.
Overnight lows will range between 5 above to 5 below...expect parts
of the western Adirondacks will be -5 to -10 degrees.

Temperatures aloft will be moderating very quickly on Monday...as the cold
core shifts away from the region. Temperatures look to reach into the 20s
for most areas for highs. At this point...there is a slight to low
chance of some light snow on Monday depending on the exact speed/track
of a northern stream system...but this is still far from certain.

Between Monday night and Wednesday...the forecast gets much more
uncertain...but there is the potential for a high impact system
during this time period. A system moving through the southern
stream across the deep south may start to turn up the eastern
Seaboard...and may merge/phase with the northern stream system
heading towards the area. The 00z European model (ecmwf)/00z gefs/00z ggem all hint
at the potential for a significant amount of quantitative precipitation forecast with the system
which could track over/close to the region. Meanwhile...the 00z GFS
has these systems staying separate...and the southern stream system
generally remaining south/east of the region. If it occurs as shown
in some of the gefs members or latest European model (ecmwf)...p-type would be a
major issue with this system...especially considering the 00z European model (ecmwf)
solution...which could bring snow/mixed precip/rain...and
potentially back to any or all of the above. The storm track...which
is still very much in question...will determine the exact p-type and
amounts...and it could wind up tracking over I-95 or the Connecticut
River valley. However...it/S probably Worth mentioning that the
very cold Arctic air arriving this weekend will be tough to dislodge
at low levels...so a period of mixed precipitation is certainly a
possibility. Due to this still being days 7-8 and large amounts of
uncertainty regarding storm track/timing...will not include in severe weather potential statement
just yet...but will continue to closely monitor model trends. Have
gone with high chance probability of precipitation for now between Monday night and Tuesday
night...and will allow temperatures to rise above freezing by Tuesday afternoon
across much of the area.

&&

Aviation /18z Wednesday through Sunday/...
through 18z Thursday...primarily VFR conditions for the taf
locations through the period...though could see a brief period of
MVFR with a snow shower at kgfl this afternoon...and with invervals of
ceilings 2-3kft at psf during the overnight hours. Winds are
generally light S-SW...will become light west during the overnight
period. During the daylight hours Thursday...steeper low-level lapse
rates and increasing p-gradient will result in sustained winds
10-15kts...with some gusts 20-24kts after 14z Thursday.

Outlook (18z Thursday through sunday)...

Thursday through Thursday night: low operational impact. Breezy northwest
winds...gusts to 25kts possible through Thursday afternoon. Slight chance
of shsn.

Friday through Friday night: moderate operational impact.
Chance of shsn Friday. Possible snow squall with brief IFR
conditions Friday night into the pre-dawn hours Saturday.

Saturday through sunday: low operational impact. Northwesterly wind gusts
to 25 kts possible Saturday (mainly late morning through
afternoon).

&&

Hydrology...
tidal issues along the Atlantic Seaboard are resulting in higher
than normal tides up the Hudson River. It appears Poughkeepsie
will experience tidal impacts which may persist the next couple of
days. Otherwise...no other hydrological issues are expected at
this time.

With an approaching upper level trough...some snow showers and
flurries are possible through Thursday. Total liquid equivalent
will be very light...generally less than a tenth of an inch at any
one location...perhaps a bit higher across the western
Adirondacks.

With colder temperatures arriving by later in the week and the
upcoming weekend...ice cover on rivers and lakes will increase in
coverage and thickness. Temperatures should remain completely
below freezing from Wednesday night through the rest of the week.

For details on specific area rivers and lakes...including
observed and forecast river stages and lake elevations...please
visit the advanced hydrologic prediction service /ahps/ graphs on
our website.

&&

Aly watches/warnings/advisories...
CT...none.
New York...Lake effect Snow Advisory until 6 PM EST Thursday for nyz032-
033-038.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...kl/11
near term...irl/11/WFO btv
short term...kl/11
long term...frugis
aviation...weather forecast office btv
hydrology...kl/11

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