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Area forecast discussion 
National Weather Service Albany New York
204 am EDT Tuesday Jul 26 2016

Synopsis...
with the passage of a cool front overnight a slightly less humid
air will move into the region for Tuesday and Wednesday. However
temperatures will continue to be rather warm with a partly to
mostly sunny sky.

&&

Near term /until 6 am this morning/...
a couple of isolated showers continue to move southeastward
across the area while weakening early this morning as a cold/cool
front makes its way across the region. Higher pressure will begin
to build in late at night/early in the morning. With wet ground
in some area and light to calm winds expect some patchy fog to
develop. Looking at lows will be in the 60s.

&&

Short term /6 am this morning through Thursday/...
sunny and dry weather is expected Tuesday and Wednesday with
breezy winds at times Tuesday and lighter winds Wednesday.
Boundary layer temperatures do not cool much but the humidity will
be considerably less. A weak reinforcing cold front will approach
from Canada late Wednesday and Wednesday night with a little bit
or warming of the boundary layer through the day Wednesday.

So, highs Tuesday in the 80s to lower 90s. Highs Wednesday a
couple of degrees warmer. On Thursday, the weak cold front is
expected to cross our region with scattered thunderstorms and
mixed clouds and sun. Highs Thursday in the 80s to around
90...some upper 70s southern Adirondacks.

&&

Long term /Thursday night through Monday/...
still a rather low confidence forecast at this time as upstream
attempts to ridge amplification (4-corner into the southern portions
of the Pacific northwest) while as upper level polar lows transverse
east-northeast across central and eastern Canada. Inbetween these
will be a fairly fast quasi-zonal flow across the northern Continental U.S. As
some sub-tropical moisture advects northeast toward our region
through the end of this week.

The European model (ecmwf) remains the most amplified with a nearly cut-off upper low
evolving over the central Great Lakes through the end of this
weekend and the start of the weekend. Meanwhile, the GFS/ggem are
more progressive and flat/zonal flow through the period. Per
ensemble trends, we will favor toward slight amplification with a
surface wave developing over the Tennessee Valley Thursday night and
tracking along a quasi-stationary frontal zone through Friday with a
good chance for a period of wet weather. We will place graduated
pops with the highest values south of i90 at this time. Then
heading into the weekend we will favor toward lesser amplification
with a decrease in pops under partly cloudy conditions.

Temperatures through the period should average near normal through
the period with low confidence precipitation forecasts to remain
near or slightly below normal.

&&

Aviation /06z Tuesday through Saturday/...
a cold front continues to move across the region this morning. High
pressure will build in from the Midwest and lower Great Lakes region
late this afternoon and tonight.

Due to recent wet ground...and clearing skies a brief period of
MVFR/IFR mist/fog is possible at kpou/kgfl/kpsf and kalb. The
greatest threat for IFR mist/fog will be at kpou/kpsf especially
between 08z-11z. The winds will increase from the west to northwest at 11z-
15z for the boundary layer to dry out...and VFR conditions to
quickly return.

Scattered-broken stratocumulus clouds with some cirrus will prevail late this
morning into the afternoon. The skies will clear towards 22z-
01z/Wednesday with the sfc ridge building in.

The winds will be light and variable in direction at 5 kts or less
early this morning...and then shift to west btwn 11z-15z at 5-10
kts...and then increase from the west to northwest at around 8-12 kts in the
afternoon before becoming light towards 00z/Wed. A few gusts close
to 20 kts are possible at kalb this afternoon.

Outlook...

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

&&

Fire weather...
westerly wind with gusts into the teens and 20s Tuesday
afternoon...

Showers and thunderstorms will move across the region this
evening. Some of the thunderstorms may be strong to severe, with
gusty winds and heavy rainfall. With the passage of a cold front
tonight, slightly less humid air will move into the region for
Tuesday and Wednesday, but temperatures will continue to be
rather warm with a partly to mostly sunny sky.

Rh values tonight and Tuesday night are expected to be 75 to 100
percent. Minimum relative humidity values Tuesday afternoon will be 40 to 55
percent and on Wednesday 35 to 45 percent.

Light west winds below 15 mph tonight will become west to
northwest Tuesday at around 15 mph with gusts possible over 20
mph. Winds diminish to light Tuesday night and increase to around
15 mph Wednesday.

&&

Hydrology...
showers and thunderstorms are expected to move across the area
into this evening as a cold front approaches from the Great Lakes
region. Some storms will be capable of producing locally heavy
rainfall. Ponding of water on roadways along with some minor
urban flooding of low lying and poor drainage area is possible.

High pressure will build in and bring fair weather to the area
through the middle of the week. Unsettled weather is expected late
in the week through the weekend.

Flows continue to be well below normal for late July at many
locations in the Hydro service area, especially our western New
England area.

For details on specific area rivers and lakes, including observed
and forecasted 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...iaa/bgm/NAS
near term...iaa/bgm/NAS
short term...NAS
long term...bgm
aviation...wasula
fire weather...NAS
hydrology...NAS

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