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Area forecast discussion 
National Weather Service Albany New York
610 PM EDT Monday Jul 25 2016

Synopsis...
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.

&&

Near term /until 6 am Tuesday morning/...
Severe Thunderstorm Watch 415 cancelled in New York but remains in
effect for northwest CT.

Thunderstorms below severe limits in the Mid Hudson valley.
Storms will enter Litchfield County CT through the hour and will
see if any new development occurs in the eastern part of the
County.

Once the storms exit, clearing and some low level drying will
spread across the region. If winds go calm...there could be some
fog but the steady drying at low levels perhaps just a light wind
from time to time could keep the temperature/dewpoint spread just
enough to prevent much areal coverage of fog. Lows in the
60s...with around 60 in northern areas.

&&

Short term /6 am Tuesday 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 /22z Monday through Saturday/...
first round of showers and thunderstorms moving over taf sites
between 1730 and 1900z. Some brief reductions to MVFR/IFR
conditions will be possible in thunderstorm at kpou. Other sites
are north of thunderstorms and just rain showers are more likely.

Second round of showers and thunderstorms are expected at the taf
sites between 25/22z and 26/00z.

VFR conditions are expected after 00z/Tue...but some MVFR/IFR
mist is expected to develop after 04z at the taf sites.

The winds will be south to southwest at 5-12 knots this afternoon.
Some gusts in the 15-20 knots range will be possible in the
afternoon from the southwest before becoming light after 00z/Tue.

Winds will be much stronger, and variable in direction in and near
any thunderstorms.

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...tsra.
Thursday night: moderate operational impact. Chance of rain showers...tsra.
Friday: 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...NAS
near term...NAS
short term...NAS
long term...bgm
aviation...sand
fire weather...NAS
hydrology...NAS

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