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Area forecast discussion 
National Weather Service Albany New York
944 am EST Sat Feb 6 2016

Synopsis...
weak high pressure is expected to dominate our weather over the
weekend. A fast moving...clipper...low pressure system will pass
to our north over the weekend with little impact on the local
area. Some snow is possible for Monday night and Tuesday.

&&

Near term /until 6 PM this evening/...
as of 940 am EST...some scattered snow showers and flurries were
occurring across the southern Adirondacks and Mohawk Valley. Most
of the precipitation was on the light side and will continue
across this area into this afternoon. Have increased the probability of precipitation
across this area. Further east the precipitation was weakening as
it encounters drier air in the Hudson Valley. The snow showers are
expected to gradually shift northward this afternoon as low level
flow turns more southwest through the day. Some middle and high
clouds are spreading into the region and we should see filtered
sunshine through the day with southwest winds. Even with the
filtered sun...temperatures should climb to highs in the middle 30s
to lower 40s.

&&

Short term /6 PM this evening through Monday night/...
weak high pressure will still be in control tonight but a cold
front will begin to approach from Canada by daybreak and through
the day Sunday as upper energy tracks east through southeast Canada. More
intervals of high clouds can be expected Sunday with light winds.
Boundary layer temperatures will warm a little ahead of the cold
front but very light winds Sunday could limit mixing. Highs
Sunday in the lower to middle 40s...some 30s in northern areas.

Sunday night into Monday...a southern stream system is expected to
track across the Middle Atlantic States and offshore...with a general
consensus from sources of guidance and ensembles for the primary
upper energy and low level forcing to track well south and east of
New England. There are still some uncertainties...though...because
digging...trailing...strong northern stream energy may have some
influence in how far north and west the steadier precipitation
gets...depending on its influence on the track of the southern
stream system...if at all.

Also...as the coastal system develops...there are some
indications that there could be a somewhat long fetch of easterly
boundary layer flow off the ocean into the northeastern U.S. Which
could result in a more expanded precipitation shield. Lots of
ifs...which again illustrates the uncertainty this far out. At the
very least...the digging northern stream energy and moisture from
the Great Lakes could bring fairly widespread snow shower activity
Monday and Monday night to the region. Time will tell how
everything sorts out in the next couple of days.

So...generally becoming cloudy Sunday night and staying mainly
cloudy Monday and Monday night. On Monday...indicating high
chances bordering on likely for snow in the middle Hudson Valley and
northwest CT. Smaller chances to the southern Berkshires and southern Vermont
with slight chances a little north and west of those areas. By
Monday night...most areas should see high chances for snow. Highs
Monday in the lower 30s north and middle to upper 30s south.

&&

Long term /Tuesday through Friday/...
more winter like conditions are expected during the long term
portion of the forecast...with temperatures trending from near
normal on Tuesday to below normal towards the end of the work week.
There will be multiple chances for mainly light snow or snow showers
during the period as well.

The period starts out on Tuesday with a highly amplified pattern
across the Continental U.S. And a sprawling upper level trough moving into the
eastern half of the country. Medium range models indicating short
wave troughs moving through the flow aloft will spawn a low pressure
system just off the middle Atlantic coast on Tuesday. However...there
is considerable uncertainty with regards to the eventual strength of
this system...as it may not have much baroclinicity to work with.
This will still be a system to keep an eye on...as depending on the
exact track could bring at least a light snowfall to parts of the
region...especially south and east of the capital district. Will
mention chance probability of precipitation for now...with the highest values across western
New England and the middle Hudson Valley. At this time it appears any
snowfall will be light...however there are several factors that may
allow the storm to take a more westerly track which would result in
greater snowfall. Stay tuned.

By Wednesday any potential storm should be well offshore and far
north and east of our region. With the upper trough axis moving
through along with a northwest flow aloft...scattered snow showers
will be possible. An Arctic cold front looks poised to cross our
region Wednesday night into early Thursday morning. Additional snow
showers will be possible ahead of and along the front...while the
main story will be much colder Arctic air surging southward into the
region.

A small area of high pressure may briefly build in Thursday
night...before the next potentially strong Arctic front could usher
in the coldest air of the season thus far starting late Friday. We
are still about a week away from this...but will note the GFS/European model (ecmwf)
have been pretty consistent with showing sub-500 decameter thickness
values over the region by the first half of next weekend.

&&

Aviation /15z Saturday through Wednesday/...
VFR conditions will prevail at the kalb/kpou/kpsf/kgfl terminals
through the 24 hour period ending 12z Sunday. Skies starting out
mostly clear or partly cloudy early this morning...but middle level
clouds will gradually increase later in the morning and afternoon
as a weak disturbance moves across the region. No precipitation is
expected. Cloud cover will decrease after dark as a weak ridge of
high pressure builds in.

Winds today will be south-southwest around 5-10 kts...becoming
light and variable after dark.

Outlook...

Sunday night: no operational impact. No sig weather.
Monday: low operational impact. Slight chance of snow.
Monday night: moderate operational impact. Chance of snow.
Tuesday: moderate operational impact. Chance of snow.
Tuesday night: moderate operational impact. Chance of snow.
Wednesday: moderate operational impact. Chance of shsn.
Wednesday night: low operational impact. Slight chance of shsn.
Thursday: low operational impact. Breezy. Slight chance of shsn.

&&

Hydrology...
no significant Hydro concerns expected over the next 5 days as any
precipitation will be light or in the form of snow.

The third winter Spring flood potential for the season was issued
on February 4th.

Highlights...refer to the products for details (albesfaly):

Due to below normal snow cover and river ice...potential for
snowmelt and ice jam flooding is low for this time of year.

Although water supply levels are not a concern at the moment...there
is currently very little snow water available for Reservoir recharge
across the outlook area. It will take a steady supply of rain and
snow through Spring into Summer for reservoirs to maintain adequate
levels.

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...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...NAS
near term...11/NAS
short term...NAS
long term...jpv
aviation...jpv
hydrology...NAS

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