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Area forecast discussion 
National Weather Service Albany New York
739 PM EDT Friday Oct 31 2014

Synopsis...
a potent upper level disturbance passing to our south tonight...will
phase with another disturbance well east over the Atlantic Ocean.
These systems will bring light precipitation in the form of rain
showers for later tonight into Saturday...turning to snow showers
Saturday night...mainly across the higher elevations. Cold...windy
conditions are expected on Sunday. After a cold start...Monday
should be fair with moderating conditions.

&&

Near term /until 6 am Saturday morning/...
as of 715 PM...skies are now mostly cloudy across the Albany
forecast area. No precipitation echoes on radar. Temperatures
range from the upper 30s in the higher elevations to the low 50s
in the middle Hudson and lower Housatonic valleys. Nearest
precipitation echoes to the west are over The Finger lakes...and
are relatively stationary. Nearest precipitation echoes to the
east are over eastern Connecticut and moving north. Probability of precipitation remain
low this evening. Minor adjustment to gridded database based on
latest observations.

Previous...
tricky call on overall sky cover conditions tonight...especially through
midnight. It appears that the lower clouds have had a difficult
time expanding westward...most likely due to some downsloping from
The Greens and Berkshires. And the high clouds have shifted a bit
farther east...mainly into New England. We expect lower
clouds...from moisture pooling across southeast New England and
Li...to expand north and west...into the middle Hudson Valley/northwest CT and southeast
Catskills over the next several hours...and then possibly further
north and west later tonight.

The combination of an upper level impulse currently riding north
across eastern Virginia...and low level moisture advancing north and west
from southeast New England and Li...should allow for some spotty light
rain showers or patchy drizzle to develop later this evening later
this evening across portions of northwest CT...the middle Hudson Valley...and
southeast Catskills. These showers should remain generally across southern
areas...although can not rule out a few isolated showers further north
and west closer to daybreak. Additional showers of rain...and snow will
be possible across portions of the western Adirondacks later tonight.

Min temperatures will be highly dependent on sky cover...with temperatures possibly
dropping rapidly this evening where breaks in the clouds
linger...before thicker clouds develop later tonight. Have generally
went with or slightly above a mav/met MOS blend for min
temperatures...which may occur around or just after midnight in some
areas...before gradually rising again toward daybreak.

&&

Short term /6 am Saturday morning through Monday/...
Sat-Sat nt...despite model guidance insisting on most of the
precipitation associated with the developing offshore storm system
remaining well south and east of the region...still admittedly not
overly confident that at least some bands of precipitation approach and
possibly affect portions of at least southern Vermont and western Massachusetts late
Sat afternoon into sun am. Water vapor imagery reveals 4 distinct
shortwaves...with the main feature currently translating southward
from the Great Lakes...and yet another fast moving impulse racing southeast
into northwest Ontario. It is this last feature...in northwest Ontario...that has
some potential to pull things slightly farther west than current
models indicate. At the very least...expect some rain showers to
develop across the region during Saturday...especially in the afternoon
hours...with the greatest coverage expected across western New
England and the middle Hudson Valley. Then...as the low rapidly
develops offshore with significant convection...current projections
indicate that most of the steadier precipitation remains confined closer
to the New England coast. However...there remains a low
probability that a band of steadier precipitation advances northwest or
west around the the developing low...especially late Sat nt or early
Sunday. So...will keep chance probability of precipitation for western New England well into
Sat nt...decreasing to slight chance elsewhere. However...will have
to very closely monitor radar trends...and also near term forecast
guidance from the rap/hrrr...which may give some near- to short-
term hints that precipitation may be trending farther north and west. Thermal
profiles support mainly rain in valleys through Sat...with some
snow possible across higher terrain late in the day...especially
elevations greater than 1500 feet. Then...depending on how much
dynamical cooling can occur...rain and or rain showers should
change to snow across all elevations above 1000 feet Sat
evening...and perhaps even in valley areas later Sat nt. Current
gridded database includes some minor snowfall accums of up to an
inch across the higher elevations of western New England...and
also portions of the eastern Catskills...by sunrise Sunday.
Also...up to one half inch is expected across the southern
Adirondacks. However...again...there remains a small probability
that greater amts could occur...at least across southern
Vermont/western Massachusetts and the higher terrain of northern Litchfield Colorado if
the precipitation trends farther west.

Otherwise...temperatures should reach the upper 30s to middle 40s across
higher elevations...and middle 40s to lower 50s in valleys for
Sat...then fall into the Lower/Middle 30s for Sat nt in valleys...with
possibly some 20s across higher elevations. Brisk north winds will
develop Sat afternoon into Sat nt...and may gust to 25-30 miles per hour...especially in
some north/S oriented valleys.

Sun-Mon...after any lingering precipitation should taper off sun am...with
clearing by afternoon. It should be windy and cold Sunday...with
partly to mostly sunny skies in valleys...and mostly cloudy for
higher terrain. North to northwest winds may still gust to 35-45 miles per hour
across portions of southern Vermont/western Massachusetts and the Taconics...and
possibly portions of the Mohawk River valley and southeast Catskills...and
25-35 miles per hour elsewhere. Maximum temperatures should reach the Lower/Middle 40s in
valleys...except possibly 45-50 in portions of the middle Hudson
Valley...with mainly 30s to near 40 for higher elevations. Clear
skies and diminishing winds late sun nt should allow temperatures to reach
the lowest levels of the fall season...generally in the 20s...with
some teens possible across some higher elevations. Maximum temperatures on Monday
should reach the upper 40s to lower 50s in valleys...and Lower/Middle
40s across higher elevations. Sun nt-Monday should remain generally
clear...although some patchy clouds could pass across portions of
the Catskills late sun nt/early Monday.

&&

Long term /Monday night through Friday/...
high pressure will be situated off the eastern Seaboard to start the
extended period. This will allow for dry weather for Monday night into
Tuesday. Min temperatures will be seasonable chilly for Monday night with
upper 20s to middle 30s...but look to be above normal on Tuesday with
highs well into the 50s.

A frontal system will be moving towards the area for Wednesday into
Thursday. This will allow for clouds and possibly some rain showers
as the frontal boundaries moves across the area. With the clouds and
possible precipitation...overnight lows will be milder than recent
nights...with mainly 40s across the area. Daytime highs look to be
in the 50s...with some upper 40s across the high terrain.

In the wake of the surface frontal boundary...cooler air will pour into
the region for the late week period. There may be a few lingering
cyclonic flow showers of rain or snow for Thursday night into
Friday...with temperatures turning cooler than normal.

&&

Aviation /00z Saturday through Wednesday/...
VFR conditions should prevail through tomorrow at the Hudson
Valley taf sites. However...there will be a ceiling between 3000
feet and 5000 feet. VFR becoming MVFR is expected at kpsf as the
ceiling lowers to around 15oo feet mean sea level later Saturday. After
02z...some showers could begin to approach the kpou area and
continue into Saturday. By Saturday afternoon...all taf sites have
a threat of rain showers. Visibilities should remain VFR through
the period except at kpsf where they are forecast to become MVFR
later Saturday.

Winds from the north to northeast are expected tonight at less
than 10 knots...then winds increase to 10 to 15kt from the north on
Saturday.

Outlook...

Saturday night: moderate operational impact. Scattered rain showers...shsn.
Sunday: moderate operational impact.Windy with gusts to 31.0 no sig weather.
Sunday night: low operational impact.Breezy no sig weather.
Monday: low operational impact.Breezy no sig weather.
Monday night: no operational impact. No sig weather.
Tuesday: no operational impact. No sig weather.
Tuesday night: low operational impact. Slight chance of rain showers.
Wednesday: moderate operational impact. Chance of rain showers.

&&

Fire weather...
a potent upper level disturbance passing across the Great Lakes will
dive to our south tonight and phase with another disturbance
offshore. The net result of this will be only light precipitation in
the form of rain showers for later tonight into Saturday...turning
to snow showers Saturday night...mainly across the higher
elevations. A powerful storm offshore will drive the coldest airmass
of the season over US by Sunday...along with gusty winds.

&&

Hydrology...
no widespread hydrologic concerns over the next five days.

An upper level shortwave trough produces some scattered rain and
snow showers late tonight through Saturday night.

Any precipitation over the next few days will be light...and basin
average amounts will generally be a tenth of an inch or less through
early Sunday. Some of the precipitation will actually fall as light
snow.

Dry weather Sunday will continue into early next week with no big
precipitation makers in sight.

River levels will hold steady or slowly fall through the weekend.

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...hwjiv/kl
near term...snd/kl
short term...kl
long term...frugis
aviation...snd/NAS
fire weather...kl
hydrology...kl

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