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

Synopsis...
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
Albany.

&&

Near term /until 6 PM this evening/...
for today...expect dry conditions across the northwestern third of
the forecast area with mostly cloudy skies this morning giving way
to partly sunny skies this afternoon. Across the southeastern two
thirds of the forecast area expect some steady rain at least
through the morning hours with a slight chance of thunderstorms
this afternoon. The threat of flash flooding has ended as rainfall
amounts even in areas which see steady rain will be less than 2
inches. There will be considerable cloudiness across the
southeastern two thirds of the region today which will limit
temperatures. Thus temperatures will be much lower than the last
several days. Highs today 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 limited...so 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 sfc...an 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 /08z Friday through Tuesday/...
low pressure continues to move along a stationary front over
southern New York and New England this morning. The low pressure system
will pass to the east later this morning...and the front will
slowly move southward this afternoon with high pressure gradually
ridging in from southeastern Canada.

The shower coverage is most numerous south and east of kalb...to
kpou and kpsf. Expect MVFR ceilings/visibilities to potentially develop over
kpou/kpsf btwn 06z-08z...and continuing until 12z-14z. A short
period of IFR ceilings/visibilities is also possible at kpsf prior 12z.
Further north to kalb/kgfl a shower is possible btwn 08z-11z at
kalb...and a vcsh group was used at kgfl with a fine gradient in
the rainshield to the system.

In the late morning into 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.

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

Outlook...

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

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
Saturday.

&&

Hydrology...
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).

A widespread rainfall is expected across the southeastern two
thirds of the hsa today, although model guidance continues to be
unclear on the exact timing, amounts and duration of the rain.
This rainfall is much needed, as river and stream flows are below
normal across much of eastern New York and western New England.
The best chance for a soaking rain looks to be across the
southeast portion of the area, from the Mid Hudson valley and
Taconics, eastward to the Berkshires and Litchfield Hills.
Areas from the eastern Catskills through the Mid Hudson valley
could see up to 2 inches of rain through today. Elsewhere in the
hsa, an inch or less of rainfall is expected.

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...
CT...none.
New York...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...11/NAS
near term...11
short term...11
long term...wasula
aviation...frugis/wasula
fire weather...11
hydrology...11/NAS

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