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Area forecast discussion 
National Weather Service New York New York
748 PM EDT Tuesday Jul 26 2016

Synopsis...
a weak front will move south of Long Island this evening. High
pressure will build from the west going into Wednesday, and move
east by Thursday. A weak cold front will approach the region
Thursday night, and remain in the vicinity as a few waves of low
pressure pass nearby into the weekend. High pressure builds back
in for early next week.

&&

Near term /until 6 am Wednesday morning/...
some minor adjustments were made to the forecast database to
better match observed trends.

A weak cold front will move south of Long Island this evening
with winds becoming more northerly behind it. A few remaining
gusts this evening will diminish later this evening and overnight.
Clouds will increase with mostly high level clouds moving in from
the west. These will decrease later tonight with weak high
pressure building in.

Sided with the cool end of guidance for lows tonight, with a wide
range of temps, from the 70s invof NYC, to the 60s most elsewhere,
to some upper 50s in some interior valleys.

&&

Short term /6 am Wednesday morning through Wednesday night/...
models continue to agree on the region lying between a closed low
over Quebec and flat southeast US ridging, with zonal flow aloft.

At the surface, high pressure will give way to weak thermal
troughing developing in the afternoon. Hot conditions will
continue, with highs 90-95, near or slightly above the warmest MOS
guidance. Dewpoints in the upper 50s and lower 60s will keep heat
index values at or just below ambient temperatures, so do not
plan to extend the heat advisory for NYC.

Temps Wed night will be similar to those forecast for tonight,
will perhaps a little more widespread upper 50s across the
interior.

&&

Long term /Thursday through Tuesday/...
models are in general agreement with the 500 mb pattern across North
America through the long term. A cutoff low over northern Quebec
Thu morning will be slow to move NE through Friday keeping
a broad trough across the NE quarter of the US. As the cutoff
lifts into the Maritimes heights will slowly begin to rise as a
deep anticyclone reestablishes itself over the central US.

Somewhat of a complex scenario at the sfc during the first half of
the period. A cold front approaches from the west as a wave of low
pressure ejects out of the mid-Mississippi Valley Thu/Thu night.
12z nwp guidance have come into better agreement that this low
will impact the area on Fri into Fri night. However...there are
still differences with timing...track and strength that need to be
resolved. Have increased pops to likely on Fri since there is
better agreement amongst the guidance. Instability not very
impressive...although there could be some rumbles of thunder.
There is also the potential for locally heavy rain with pw's
forecasted to be in excess of 2 inches. Once the wave moves by
there should be a lull on Sat although with the front remaining
close to the area have kept schc pops.

Another wave may impact the area Sat night into sun...although the
long range models diverge at this point. Have kept low chc pops
for now...but it could end up being mostly dry if the wave doesn't
materialize. The boundary is finally nudged southward early next
week as high pressure builds in from Canada.

One final day with 90 degree temps Thu...then highs will be
closer to normal levels into early next week.

&&

Aviation /23z Tuesday through Sunday/...
VFR as high pressure builds from the west through Wednesday.

West-northwest-northwest winds will diminish to less than 10 knots this evening and
back to the north at city terminals. At outlying terminals, the
winds will go light and variable. Northerly winds veer to the
west-west-northwest after 12z except at klga where winds back more to the NE
late tonight into Wednesday morning.

Winds will veer to the west-southwest-SW into the afternoon with seabreezes
at coastal terminals, earliest along the CT coast.

... Metro enhanced aviation weather support...

Detailed information, including hourly taf wind component
forecasts, can be found at: http:/www.Weather.Gov/zny/n90

Kjfk taf comments: winds settle below 10 knots through 03z and back
to the northwest and then north overnight.

Klga taf comments: winds settle below 10 knots through 03z and back
to the northwest and then north-NE overnight.

Kewr taf comments: winds settle below 10 knots through 03z and back
to the northwest and then north-NE overnight.

Kteb taf comments: no unscheduled amds expected.

Khpn taf comments: no unscheduled amds expected.

Kisp taf comments: no unscheduled amds expected.

Outlook for 00z Thursday through Sunday...
Wednesday evening-Thursday...VFR. Isolated showers and
thunderstorms possible Thursday afternoon, mainly northwest of the NYC
terminals.
Thursday night-Sunday...MVFR or lower possible with a chance of
showers and thunderstorms. The best chance looks to be on Friday.

&&

Marine...
sub-Small Craft Advisory conditions will prevail through Wed night.

There is a low chance of Small Craft Advisory conds on the waters Fri depending on
the track and strength of low pressure passing near the area.
Otherwise...sub-advsy conds are expected through the rest of the
period.

&&

Hydrology...
there is potential for significant rainfall from late Thursday
night into Friday night. Locally heavy rainfall is possible...which
may cause flooding concerns although it is still too early for
specifics.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...none.

&&

$$
Synopsis...Goodman/24
near term...Goodman/jm
short term...Goodman
long term...24
aviation...ds
marine...Goodman/24
hydrology...Goodman/24

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