Area Forecast Discussion
Issued by NWS Upton, NY

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911
FXUS61 KOKX 190837
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
437 AM EDT Wed Aug 19 2026

.WHAT HAS CHANGED...
Timing of showers on Thursday has become a bit more fine tuned,
however, uncertainty still exists in total expected rainfall.
QPF and PoPs have trended higher in the latest forecast update.

The WPC has introduced a marginal risk of excessive rainfall for
northeast NJ, NYC and western Long Island for Thursday.

&&

.KEY MESSAGES...
1) Showers and potential thunderstorms are expected on Thursday.
Embedded stronger thunderstorms and heavy downpours are possible.

2) Unsettled weather this weekend.

&&

.DISCUSSION...
.KEY MESSAGE 1...
A cold front approaches today and will stall over or near the area
through the weekend. The persistent upper level trough over the
eastern US continues through this period as well. Shortwave energy
currently over the Northern Plains will round the base of this
trough and aid in development of a wave of low pressure that
will pass near the area. While forecast PoPs have increased to
widespread likely, exact strength and location of this wave will
determine the amount of rainfall we see.

Both global guidance and CAMs are struggling on location of the
frontal wave. One thing to note is that even the solutions
farther north (wetter) do not have very impressive CAPE
profiles and any instability that is available appears to be
confined to the lower levels. This could mean some of the higher
hourly rates that certain CAMs are outputting might be
overdone. Regardless, isolated heavy downpours can not be ruled
out given pwats around 2 inches and decent low level lift.
Forecast QPF is a bit higher than the latest deterministic NBM
with 0.75 inches for northeast NJ, NYC and western Long Island
and 0.25 to 0.50 inches elsewhere. Isolated higher amounts are
possible, especially for northeast NJ, NYC and Long Island.
While flash flooding is not expected, it can not be completely
ruled out for these areas and the WPC has introduced a marginal
risk of excessive rainfall.

While thunderstorms are possible, the severe potential is likely
farther south of our area. While shear values are impressive
(0-6km bulk shear of 45-50kt), the aforementioned weak/low CAPE
profile will be a limiting factor. The SPC has continued to
keep the marginal risk south of our area. Strong wind gusts in
any thunderstorms or stronger convective showers are possible
given up to 500 j/kg of DCAPE.

.KEY MESSAGE 2...
The front looks to push farther offshore for Friday before
additional waves of low pressure pass nearby over the weekend.

There looks to be another period of potential moderate to heavy
rainfall, specifically during Saturday afternoon and evening.
Once again, guidance is struggling with strength and location of
the offshore wave that will form ahead of a negatively tilted
upper trough. The WPC has a marginal risk for the entire area.
Thunderstorm activity with this event is expected to remain
mainly offshore, although isolated thunder along the coast can
not be ruled out.

With the stalled front still offshore on Sunday, a cold front
approaches from the west. This brings a chance of showers and
thunderstorms Sunday afternoon/evening. It is too far out to
talk specific details on strength of showers/thunderstorms, but
it is worth noting that the latest CIPS and CSU MLP are hinting
at potential isolated severe thunderstorm activity for NYC and
north and west.

&&

.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
Weak high pressure remains near the region today.

Mainly VFR expected for the TAF period. The exception is for
outlying and coastal terminals early this morning with a few
pockets of low stratus that forms (mainly KGON, KISP, KHPN). A
brief period of prevailing sub VFR is more of a possibility for
KGON.

Light N/NW winds early this morning becomes more W/SW by
afternoon, mainly 7-10kt. Winds become light again tonight.

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

Low chance of low stratus late overnight, mainly 07Z-11Z. Not
currently reflected in TAFs for city terminals.

.OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...

Wednesday night: VFR.

Thursday: Chance of showers and thunderstorms with MVFR or lower at
times mainly during the second half of the afternoon and evening.

Friday: Mainly VFR. Low chance of showers with MVFR or lower at
times.

Saturday: Chance of showers with MVFR or lower at times.

Sunday: Chance of showers with MVFR or lower at times.

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

&&

.MARINE...
Sub-SCA conditions currently forecast through the start of next
week. There is a low chance for forecast winds and waves to trend
higher depending on location and strength of a wave of low pressure
on Thursday evening.

Rip Currents: With winds forecast to be less than 10 kt currently
for today and Thursday, and a weakening swell, there is a low risk
of rip currents.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$

DISCUSSION...JT
AVIATION...BC
MARINE...JT