144
FXUS61 KOKX 202037
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
437 PM EDT Sun Sep 20 2026

.WHAT HAS CHANGED...
Gale watch posted for the ocean waters with the potential for
NE gales from Tuesday through the end of the week.

&&

.KEY MESSAGES...
1) Periods of rain, mainly light, will come to end from NW to
SE tonight with a cold frontal passage.

2) A frontal wave is expected to bring another chance of rain
to the area Monday night to Tuesday along with gusty NE winds.

3) A prolonged period of NE gales is possible, especially on
the ocean waters, from Tuesday through the end of the week.
There is the potential for high surf, dangerous rip currents,
and beach erosion.

&&

.DISCUSSION...
.KEY MESSAGE 1...
A frontal wave will pass to the east of the area this evening,
dragging a cold front across the area. Before that time, expect
periods of mainly light rain with an additional to tenth to
quarter inch of rainfall. Some of the guidance is hinting at
some embedded convection with the frontal wave, but just south
of the area. Airmass destabilizes into early this evening, but
its questionable as to whether we can get deep enough convection
to support thunder. For the time, have kept any mention of thunder
to the south across the ocean waters.

Behind the cold front, northerly winds increase tonight with the
potential for gusts up to 20 mph. This will persist through the
first half of Monday before briefly falling off. There will be
some partial clearing Monday, mainly across the Lower Hudson
Valley and Connecticut. Model time-height cross sections
showing a fair amount of mid and high level clouds.

Lows tonight will be on the warmer side in the mid 50s to lower
60s due to the cloud cover and winds picking up. Highs will
through will be close to 5 degrees below normal in the mid 60s
to lower 70s.


.KEY MESSAGE 2...
An anomalously strong high north of the Great Lakes will build
east through the week, bleeding south into the Northeast. At
the same time, another frontal wave will emerge from the Ohio
Valley Monday night, tracking to the south of the area. The
question is the strength of the high and how far the rain shield
will get into the area. The timing for the rain would be late
Monday night into Tuesday afternoon, the drying out from north
to south. The best chance for rain will near the NYC/NJ metro,
falling off to the north and east. There is decent frontogenetic
support. The GFS is the more aggressive of the models in
bringing some moderate rain across southern portions of the
forecast area with amounts around half an inch or so. There will
be a tight gradient from rain to nothing. Thus, this is a low
confidence forecast right now.

A tight pressure gradient will reside across the area through
the week with a prolonged gusty NE flow. Expect mainly dry
conditions from Tuesday night into Thursday with rain chances
coming up at the end of the week with the potential for a
deepening coastal low to approach the area.

.KEY MESSAGE 3...
As previously discussed the area will reside between an
anomalously strong high to the north and a broad area of low
pressure off the Mid Atlantic and Southeast coasts. Late in the
week, offshore low pressure interacts with mid latitude energy,
rapidly deepening in the Thursday to Friday timeframe. The 06Z
operational GFS which was an outlier with the other globals and
its own ensemble, now is getting some support from the 12Z
ECMWF and EC-AIFS in retrograding the deepening low toward the
forecast area. However, there is still little support from the
ensembles and the AIGFS at this time. It`s complex with the
interaction of multiple streams in the polar jet. Definitely
something to watch, especially with a prolonged period of NE
flow and increasing astronomical tides. High surf, dangerous
rips currents, beach erosion, and coastal flooding are all on
the table, but much too early to have specific details.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
A warm front slowly approaches from the south today. A cold
front moves across the terminals tonight. High pressure builds
in for Monday.

Generally, MVFR to IFR later continues through the first half
of tonight. Conditions are expected to gradually improve for the
latter half of tonight after the passage of the cold front. VFR
conditions return after 08Z in the metro terminals, and between
09-12Z for eastern terminals. Widespread showers continue this
afternoon, ending after 08Z in the metro terminals, but likely
earlier. In between showers, drizzle is possible.

SE winds around 10 kt shift to a more southerly direction later
this afternoon. Tonight, winds will shift to the NW behind the
passage the cold front. Gusts to 20 kt are possible Monday.

 ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

Amendments likely for flight category changes. Showers may end
a few hours earlier than forecast.

.OUTLOOK FOR 18Z Monday THROUGH THURSDAY...

Monday afternoon: VFR. N-NE wind gusts near 20 kt.

Tuesday through Thursday: Chance of MVFR or lower in showers.
NE wind gusts 20-25 kt Tuesday and 20 to 30 kt Wednesday and
Thursday, highest at the coastal terminals.

Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90

&&

.MARINE...
SCA is in effect for the ocean waters out to 20 nm from Monday
into Tuesday, followed by a gale watch Tue night. The gale watch
goes up on the outermost ocean zones (out 20 to 60 nm) beginning
Tue afternoon.

An anomalously strong high building across eastern Canada this
week and low pressure off the Mid Atlantic and Southeast
coasts will result in a prolonged period of strong NE flow from
Tuesday through the end of the week. There could be a prolonged
period of gales on the ocean waters and possibly the eastern
non-ocean waters, especially late in the week depending on the
magnitude and track of a coastal low. There is even a small
chance at this time for storm force gusts. Preference at this
time was to back off on the higher wind gusts of the NBM based
on latest model soundings and model consensus absent the NBM
bias correction.

Rip Currents: The rip current risk should remain moderate
through Monday. Combined seas will build to near 5 ft on Monday,
with some long period 2-ft SE swell.

Strengthening NE flow and building seas will likely produce a
high rip current risk and high surf, possibly as early as Tue
and definitely from Wed through at least Sat. As ocean swells
gradually increase to 10-15 ft with periods of about 10-11
seconds, would expect surf heights to become at least half that
high given a more longshore current vs direct
onshore trajectory.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 6 AM Monday to 6 PM EDT Tuesday for
     ANZ350-353-355.
     Gale Watch from Tuesday evening through Thursday afternoon for
     ANZ350-353-355.
     Gale Watch from Tuesday afternoon through Thursday afternoon
     for ANZ380-383-385.

&&

$$

DISCUSSION...BG/DW
AVIATION...JP
MARINE...BG/DW