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Area forecast discussion 
National Weather Service Albany New York
958 am EDT Friday Jul 29 2016

a weak cold front will settle over the southern part of the
Albany forecast area today. This front may trigger some isolated
afternoon showers and thunderstorms. Mainly fair and seasonable
weather is forecast for Saturday before a storm system approaching
from the Ohio Valley brings a threat of widespread showers and
thunderstorms on Sunday.


Near term /until 6 PM this evening/...
as of 958 am EDT...update of near term grids to account for
trends in observations, satellite loop and radar. Clouds have
broken up over all but the southeastern third of the
area. Although mslp field shows weak cold front has slipped south
of New York, dewpoint boundary is still north of forecast area.
Area still under weak cyclonic flow at 850mb. Some weak ridging
aloft beginning to develop between departing low pressure south of
Long Island and next system now near Chicago. 12z Albany balloon
sounding shows cape could reach around 1000j/kg this afternoon
based on high temperature forecast. Expect some afternoon showers
and thunderstorms to develop at least over the terrain later
today. They will be slow movers and produce some locally heavy
rain but be isolated. Highs today, based on 12z sounding, will
range from the mid 70s to lower 80s.


Short term /6 PM this evening through Sunday night/...
for tonight into the first half of Saturday...expect generally dry
conditions as a weak ridge of high pressure builds across the
region. Lows tonight will be in the mid 50s to mid 60s.

By Saturday afternoon there will be the chance of showers across
the eastern Catskills as a wave of low pressure starts to move
eastward from the Ohio Valley. Expect highs on Saturday to be in
the mid 70s to mid 80s with increasing clouds during the
afternoon. On Sunday the low pressure system will be moving across
Pennsylvania and pass south of Long Island Sunday night. This will
bringing more clouds, along with showers and thunderstorms back
into our region. At this time it looks as though much of Saturday
night and Sunday will be wet with some much needed rainfall across
the region. The showers may taper off Sunday night. Expect lows
Saturday night to be in the mid 50s to mid 60s with highs on
Sunday in the upper 60s to upper 70s. Lows Sunday night will be in
the upper 50s to mid 60s.


Long term /Monday through Thursday/...
an upper level trough will continue some scattered showers and
thunderstorms to start the week...but high pressure will build in by
Tuesday with fair and dry weather through the mid week.

Mon-Mon night...low pressure passes east of Long Island and Cape Cod
in the morning. A positively tilted long wave trough will be over
the northeast and mid Atlantic region. The trough with a short-wave
moving through will focus scattered showers and isold-sct
thunderstorms. Despite dewpoints in the upper 50s to mid
60s...heating will be only small amounts of instability
are expected. Highs will generally be in the mid to upper 70s in
the valley areas...and upper 60s to lower 70s over the mtns. The
trough axis will gradually shift downstream over New England with
the showers diminishing. Lows will fall back into the mid 50s to
lower 60s.

Tue-Tue night...the upper level trough axis lingers near
central/eastern New England. Another vort Max moves through the
trough to focus some isolated showers...especially across the higher
terrain of western New England. The showers should be tied to the
diurnal heating. At the anticyclone continues to build in
from the eastern Great Lakes over New York and New England. Sunshine will
mix with clouds. Highs will nudge closer to normal with upper 70s
to lower 80s in the major valleys...and lower to mid 70s over the
hills and mtns. Decreasing clouds Tue night with light winds should
allow for decent radiational cooling...and lows once again in the
upper 50s to lower 60s.

Wed-Thu...the medium range deterministic...ensembles...and wpc
guidance all indicate mid and upper level heights will start rising
by the mid-week over southeast Canada and the northeast. Temps will
start to rise above normal for early Aug. Sfc high pressure moves
over New York and PA by Wednesday...then drifts offshore by Thursday. H850 temps
rise back to +15c to +18c by Thursday. Highs will trend back into the
mid 80s to lower 90s by Thursday in the valleys...and over the
hilltowns...and upper 70s to lower 80s over the mtns. Humidity
levels will not be oppressive...but seasonable for the close of the
first week of the month.


Aviation /14z Friday through Tuesday/...
low pressure continues to move along a stationary front near southern
New England this morning. The front will slowly move southward
this afternoon with high pressure gradually ridging in from
southeastern Canada.

The rainshield associated with the low pressure system is shifting
east of southern New York and SW New England. MVFR/IFR conditions at
kpou/kpsf will likely linger until at least 15z. Kpsf may take
until noontime for the ceilings to get back the VFR levels. Further
north and west towards kalb/kgfl VFR conditions will return in the
late morning with just some isolated showers popping up and vcsh
groups were used.

In the afternoon...VFR conditions will return everywhere. Mid and
high cloudiness will linger through the afternoon. High clouds
will likely remain at all the taf sites into the evening with the
boundary still close to the region. Some patchy MVFR/IFR mist may
form after 04z/Sat at kpsf/kgfl/kpou...and have been included the
the tafs with IFR most likely at kpsf/kgfl.

The winds will be light and variable in direction this morning...and
then increase from the north to northeast at 4-8 kts by the
afternoon. Expect the winds to become calm again early this


Saturday night: moderate operational impact. Chance of rain showers.
Sunday: moderate operational impact. Likely rain showers...tsra.
Sunday night: moderate operational impact. Chance of rain showers...tsra.
Monday: moderate operational impact. Chance of rain showers...tsra.
Monday night: low operational impact. Slight chance of rain showers.
Tuesday: no operational impact. No sig weather.
Tuesday night: no operational impact. No sig weather.
Wednesday: no operational impact. No sig weather.


Fire weather...
a weak frontal boundary will settle south of our region early
this morning. A low pressure system is then forecast to track
along the front from the mid Atlantic states northeastward to just
south of Cape Cod today. This system could bring some much needed
rainfall to parts of the region, especially south and east of

Relative humidity values will drop to 50 to 70 percent this
afternoon, recover to 85 to 95 percent tonight, and drop to 40 to
65 percent on Saturday.

Winds will be north to northeast at less than 10 mph today through


much of the region is currently running 3 to 8 inches below normal
on annual rainfall. According to the U.S. Drought monitor, much of
the area is considered abnormally dry (category d0), and parts of
the Catskills and western New England are within a moderate drought
(category d1).

Rain fell across the southeast part of the forecast area last
night and early this morning. Based on reports, most locations
received a quarter inch or less with some isolated reports around
three quarters of an inch. There were some scattered thunderstorms
over the southern Adirondacks yesterday afternoon which produced
some local amounts around three quarters of an inch.

Dry weather returns for late Friday night through Saturday, with the
next chance of showers and thunderstorms arriving late Saturday
night into Sunday with the chances for showers and thunderstorms
lingering into early next 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...
New York...none.


near term...snd/11
short term...11
long term...wasula
fire weather...11

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