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Area forecast discussion 
National Weather Service Albany New York
502 PM EDT Sat Mar 28 2015

Synopsis...
a low pressure system will move off the New England
coast tonight. Some evening light snow or snow showers will taper
off...with clearing skies and colder temperatures expected for later
tonight. Sunshine on Sunday will help moderate temperatures a
little. Another disturbance might bring some snow showers Sunday
night...changing to rain showers on Monday.



&&

Near term /until 6 am Sunday morning/...
as of 445 PM EDT...some breaks in the clouds were occurring
across the upper Hudson Valley...while skies remained mostly
cloudy to overcast elsewhere.

Meanwhile...light snow and snow showers were ongoing across the middle
Hudson Valley and much of Litchfield Colorado CT. In fact...the overall
areal coverage of snow in these areas has increased over the last
hour. This is due to increasing middle/upper level dynamics associated
with a potent upper level impulse passing just south of this region.
So...periods of snow will likely continue across the middle Hudson
Valley and Litchfield Colorado for the next 2 hours...before gradually
tapering off from west to east after 7 or 8 PM. During this time...an
additional 1-2 inches of snowfall will be possible...especially on colder
surfaces...and across higher terrain. Most of the day...little
snowfall accumulated due to the rather high sun angle behind the
clouds. However...as the sun sets...any lingering snow that falls
will be more prone to accumulating.

Further north and west...spotty areas of light snow or snow showers will
continue until around sunset before dissipating. An additional
coating to one inch could occur where any snow showers
persist...again most likely on colder surfaces and higher elevations.

Once the upper level impulse moves further east...and the dynamics
weaken across the region...clouds should gradually thin from northwest to
southeast overnight. However...how quickly this occurs remains in question.
Have sided with the slightly milder side of mav/met MOS for
overnight mins...albeit still very cold...with forecast mins mainly
in the teens...with single digits above zero across the southern
Adirondacks.

&&

Short term /6 am Sunday morning through Tuesday/...
Sunday...a ridge of high pressure will translate across the
region. Expect mainly sunny skies...with temperatures milder than
today...reaching 35-40 in valleys and lower 30s across higher
elevations. A bit of a breeze will likely persist...making it feel
slightly colder.

Sunday night...a fast moving clipper type system will pass north
of the region on Monday. Warm advection associated ahead of this
feature will lead to increasing cloud later sun evening...with
some snow showers developing for areas mainly north and west of Albany
later at night or by daybreak Monday. In these areas...a coating
to 2 inches of snow could occur by daybreak Monday...especially across
the far western Adirondacks. In valley areas...generally only a
coating to less than an inch is expected. Little or no precipitation is
currently anticipated for most areas S and east of Albany through
daybreak Monday.

Monday...the warm front associated with the clipper system should
lift northeast across the region in the morning. Some lingering
snow/snow showers will be ongoing across areas mainly north of
Interstate 90. Milder air is then poised to move into the region
on gusty southwest to west winds later in the morning and
afternoon. The boundary layer should be warm enough for mainly
rain showers in the afternoon with the exception of snow showers
across higher elevations of the southern Adirondacks. Total
snowfall accums through midday Monday look to be generally 2-4
inches across the western Adirondacks...and 1-2 inches slightly
further S and east into the western Mohawk Valley and upper Hudson
Valley/southern Vermont...with only a coating to an inch further S
toward Interstate 90. Forecast soundings suggest low level
instability increases Monday afternoon as a cold front approaches
from the northwest. This should lead to low topped convective elements in
the form of rain showers...possibly along with some graupel. In
addition...any taller showers may be capable of producing strong
wind gusts in the afternoon. In fact...even outside of any
convective elements...winds should become quite gusty in the
afternoon...likely reaching at least 35-45 miles per hour. Temperatures may surge
upward in some valley areas Monday afternoon...into the 40s or lower
50s...perhaps even a bit warmer across portions of the middle Hudson
Valley...while most higher elevations reach the upper 30s to lower
40s.

Monday nt...cold air advection in the wake of the cold front along
with deep mixing and a fairly tight low level pressure gradient
will likely produce strong gusty winds much of Monday night...with
some gusts likely reaching into the 35-45 miles per hour range...especially within
close proximity to the Mohawk River valley/capital region and
Berkshires. Temperatures should fall into the upper 20s to lower 30s in
valleys...and lower 20s for higher elevations by daybreak Tuesday.

Tuesday...a shortwave ridge should translate across the region in the
morning. Then...a compact shortwave approaching from the lower
Great Lakes region may allow for increasing clouds...and possibly
some precipitation for late Tuesday afternoon. This is a small feature...and
degree to which models are handling this feature exhibit low
confidence at this time range. For now...just indicating chance probability of precipitation
for late Tuesday afternoon for southwest portions of the
region...highest across the eastern Catskills. Temperatures are expected
to reach the 40s in valleys...and 35-40 across higher terrain.
However...should precipitation develop late in the day...significant wet
bulb cooling may allow temperatures to fall rather rapidly with any
precipitation onset and could lead to rain mixing with or changing to
snow.

&&

Long term /Tuesday night through Saturday/...
we transition into a wet pattern during this period. Tuesday night
starts off on the dry side. Low pressure expected to track off the
Delaware-Maryland-Virginia may provide enough moisture for light rain or snow to reach
across our southern zones...otherwise things remain dry until
Thursday when a complex storm system approaches from the west.
This will be the beginning of chance probability of precipitation for the entire area
through Saturday...and this will be in the form of interchangeable
rain and snow...or a mix...with areas of sleet at times mixed in
at times...all dependent upon time of day...elevation...storm
track and temperatures.

&&

Aviation /21z Saturday through Thursday/...
outlook...

Sunday night: low operational impact. Breezy slight chance of shsn.
Monday: moderate operational impact. Windy with gusts to 34.0 chance of rain showers...shsn.
Monday night: moderate operational impact. Windy with gusts to 37.0 slight chance of rain showers.
Tuesday: low operational impact. Slight chance of rain showers.
Tuesday night: low operational impact. Slight chance of snow.
Wednesday: no operational impact. No sig weather.
Wednesday night: no operational impact. No sig weather.
Thursday: moderate operational impact. Chance of rain...sn...sleet.

&&

Fire weather...
clearing will occur later tonight along with cold temperatures.
Sunshine returns on Sunday with a west or northwest wind 10-15 miles per hour
with a few higher afternoon gusts. Relative humidity values will drop into the
30-40 percent range.

The next chance of precipitation will be late Sunday night into
Monday with showers of rain or snow. Another disturbance might
bring some more rain or snow late Tuesday into Tuesday night.

&&

Hydrology...
no Hydro related problems are anticipated through at least the
middle of the upcoming week.

Recent rainfall and snow melt has allowed for some minor rises on
rivers and streams but colder weather will slow any rises.

Rivers will likely slowly fall or hold steady through the
weekend.

During the first portion of next week...some scattered rain
and snow showers are expected between late Sunday night and Monday
evening. Little quantitative precipitation forecast is expected with this activity...and some areas
may not see precipitation.

Today...daytime temperatures will be right around freezing...and overnight
lows will below freezing. Temperatures will rise to above freeing
Sunday afternoon and again Monday afternoon. This will allow for
a slow but gradual melt on the snowpack in place... and river ice
will continue to slowly decrease and rotate away.

A rapid warmup or significant rainfall isn/T expected through the
middle of the upcoming 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...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...hwjiv/kl/jpv
near term...kl
short term...kl
long term...elh
aviation...jpv
fire weather...hwjiv/kl
hydrology...frugis/hwjiv/kl

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