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Area forecast discussion 
National Weather Service Albany New York
1032 PM EDT Monday Apr 27 2015

Synopsis...
a slow moving upper level low will continue to produce clouds
and some showers tonight...especially this evening. Drier and
warmer weather will return for the middle of the week. Some more
rain showers are possible later this week.

&&

Near term /until 6 am Tuesday morning/...
as of 1032 PM EDT...radar continues to show bands of mainly
scattered light rain showers moving from north to south over parts
of the region. Will extend mention of scattered showers through
the evening as a disturbance drifts southward across the region.
Overnight the probability of precipitation are forecast to decrease to dry conditions by
sunrise...but mostly cloudy to overcast skies will remain. Lows
will be 35 to 45.

&&

Short term /6 am Tuesday morning through Wednesday night/...
the persistent upper level low will finally start to release its
grip on the region on Tuesday as it moves slowly east. After a
cloudy/mostly cloudy start...clouds will gradually decrease to
partly/mostly sunny during the after...and temperatures will be a few
degrees warmer than Monday. Highs are forecast to be in the upper
50s to middle 60s. Northwest winds will be gusty...with wind gusts to
around 30 miles per hour possible.

For Tuesday night through Wednesday night...the region will be
between the upper low to our east...and another upper low dropping
southward from Canada and through the central Great Lakes. This
will result in dry weather during that period...but sky cover will
still average partly cloudy since there is no large surface high
in the area that could produce enough subsidence for clear/sunny
conditions. Temperatures will be seasonable with lows Tuesday and
Wednesday nights in the middle 30s to middle 40s. Highs Wednesday
generally between 60 and 70.

&&

Long term /Thursday through Monday/...
forecast models including the GFS/ECMWF/CMC have come into better
agreement for Thursday into Friday regarding a developing coastal
storm along the middle Atlantic coast. The northern stream upper level
low dropping down from the Midwest looks to phase with southern
stream energy along the southern Appalachians...and spawn
cyclogenesis off the north/S Carolina coast. The storm is then forecast
to track northeastward from there...but well off the coast. So this
results in a drier forecast for our region with a gradually
strengthening northerly flow on Friday as the cyclone deepens over
the ocean. With a broad upper level trough overhead and a few pieces
of energy moving through the trough...isolated to scattered light
showers will be possible Thursday through Friday although a
widespread soaking rain is becoming more unlikely. Temperatures look
to be near normal but a few degrees below for Friday with the
strengthening northerly flow and a extra clouds around.

The ocean storm will pull even farther away by Saturday...with a
relatively flat upper level ridge forecast to build in through the
weekend. This pattern looks to result in slightly above normal
temperatures and minimal chances for precipitation. The GFS does
show an upper low tracking just to our north on Sunday...but the
European model (ecmwf) does not have any signs of this feature. So for now will only
mention slight chance probability of precipitation for much of the area with chance over the
Adirondacks. Either way it does not look like a wash out and most of
the upcoming weekend looks dry with seasonably warm Middle-Spring
temperatures.

An even more significant warmup is possible into early next
week...as the upper ridge may build farther north allowing for a
mild south-southwest flow of air. High temperatures in the 70s may be
attainable.

&&

Aviation /03z Tuesday through Saturday/...
a trough of low pressure will continue to move southward across
the region this evening...resulting in overcast skies along with
isolated to scattered rain showers. The trough will move south of
the taf sites by later this evening and especially overnight...
allowing for some slightly drier air to bring an end to the
showers. Clouds will remain tonight...but gradual clearing is
expected to occur on Tuesday.

Conditions will be mainly VFR despite the scattered
showers...although brief periods of MVFR ceilings will occur at higher
elevation site kpsf for a time this evening. Skies will become broken
from Tuesday morning into the early afternoon...and scattered by
middle-late afternoon as drier air works into the region.

Winds will be northerly around 8-12 kts this evening...decreasing
to 7-9 kts by around midnight. Winds will become northwest and
increase to 10-15 kts with gusts of 20-25 kts by middle morning
Tuesday once mixing commences.

Outlook...

Tuesday night: no operational impact. No sig weather.
Wednesday: no operational impact. No sig weather.
Wednesday night: no operational impact. No sig weather.
Thursday: low operational impact. Slight chance of rain showers.
Thursday night: low operational impact. Slight chance of rain showers.
Friday: moderate operational impact. Chance of rain showers.
Friday night: low operational impact. Slight chance of rain showers.
Saturday: no operational impact. No sig weather.

&&

Fire weather...
gusty winds and low relative humidity values look to occur on Tuesday...

An upper level storm system will continue to impact the region
tonight with scattered to numerous light rain showers as well as
plenty of clouds. Relative humidity values will rise to 80 to 100 percent
tonight with northwest winds at 5 to 10 miles per hour. Clouds will start to
decrease late tonight.

During the day on Tuesday...the upper level storm will start to
move away from the region. This will allow skies to become partly
to mostly sunny during the afternoon. Relative humidity values falling to around
30 to 35 percent over the lower terrain during the afternoon
hours. Good daytime mixing will allow for northwest winds of 10 to 20
miles per hour...with gusts of around 30 miles per hour possible. Have coordinated with
surrounding offices and state/local officials...and at this time
there is little interest in any fire weather headlines due to the
marginal nature of the relative humidity values on Tuesday...and because
state/local officials report that fine fuels are not that dry.

&&

Hydrology...
no hydrologic concerns are anticipated at this time through this
week.

Scattered to numerous light rain showers will occur through
tonight...especially this evening...but expect less than a tenth
of an inch of rainfall. Dry weather is expected for Tuesday into
Wednesday...with a chance for rain showers returning later this
week. The amount of rainfall later this week will depend on the
exact track of a storm system moving across the southeast...as
well as influences from a northern stream upper level storm
system.

As a result...rivers and streams will generally slowly recede or
hold steady through the week. Nohrsc analysis continues to show a
very limited snowpack in place over the southern Adirondacks and southern
Green Mountains...which will continue to melt away through the
upcoming week. However...the areal coverage of this snow pack is
rather small...so it/S impact on rivers and streams of the region
will be rather minor.

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

Aly watches/warnings/advisories...
CT...none.
New York...none.
Massachusetts...none.
Vermont...none.

&&

Aly watches/warnings/advisories...
CT...none.
New York...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...gjm
near term...gjm/jpv
short term...gjm
long term...jpv
aviation...jpv
fire weather...frugis/gjm
hydrology...frugis/gjm

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