Area Forecast Discussion
Issued by NWS Upton, NY

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724
FXUS61 KOKX 101922
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
322 PM EDT Fri Oct 10 2025

.SYNOPSIS...
As one area of high pressure retreats to the east through
Saturday, another area will build to the north across eastern
Canada. A coastal storm will then impact the area Sunday into
Monday before gradually moving offshore into the middle of next
week. High pressure builds in from the Great Lakes for the second
half of the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Ahead of a digging shortwave trough over the Great Lakes, high
pressure will continue to work farther offshore. At the same
time, low pressure will begin to take shape off the southeast
coast associated with a southern branch upper low. In between
the two systems, clouds will slowly increase from the south as
a subsidence inversion over the area weakens.

Expect a much warmer night due to the increasing cloud cover
and weak onshore flow (S/SE to light and variable). Lows will
range from the lower to mid 40s inland to the lower and mid 50s
at the coast. This is a few degrees above normal.

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
Low pressure off the southeast coast on Saturday will be slow
to deepen and slow to lift north. The northern and southern
branch upper lows during this time never phase, resulting in an
elongated trough along the east coast. At the same time, there
will be a blocking high across the western Atlantic. To the
north, beneath a building upper level ridge, surface high
pressure strengthens across eastern Canada.

As the surface low lifts north, the pressure gradient will
tighten with E/NE winds beginning to increase. Expect gusts
along the coast to increase to around 20 mph in the afternoon,
and up to around 30 mph by daybreak. Farther inland, gusts will
drop off to around 20 mph.

There will also be some pockets of mainly light rain moving in
off the ocean Saturday (low-level warm advection), increasing
in coverage Saturday night, especially along the coast. A tenth
to a quarter inch of rainfall is possible during this time.

Highs Saturday will be seasonable in the mid and upper 60s.
Stayed a bit under the NBM deterministic and closer to MOS due
to the cloud cover and pockets of rain.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
A coastal storm will impact the area Sunday into at least Monday
before gradually moving offshore into the middle of next week.
Significant coastal impacts are possible on Sunday and Monday.

Key Messages:

*Coastal flood watches and warnings are in effect for the entire
coastline on Sunday and Monday. Widespread erosion is also possible
along the ocean beachfront. See the coastal flooding section below
for more details.

*Damaging wind gusts of 50-55 mph are possible across Long Island,
Brooklyn, and Queens Sunday night into Monday morning. A few gusts
to 60 mph remain possible across the Twin Forks and immediate
coastline of Long Island. A High Wind Watch remains in effect.

*Strong winds are possible across the rest of the region, with
gusts 30-40 mph possible.

*Rainfall totals of 2-3 inches are expected from Saturday night
through the day on Monday, with the highest amounts expected closest
to the coast. Minor nuisance/poor drainage flooding is possible in
typically flood-prone areas.

Low pressure along the southeast coast Sunday morning will gradually
track northward towards the region into Sunday night before stalling
along the coast of the Delmarva through the day on Monday. At the
same time, a large area of high pressure will remain anchored to the
north over northern New England and the Canadian Maritimes, while
aloft a northern stream shortwave settles over the eastern Great
Lakes.

The interaction between these three systems, in particular the
interaction between the coastal low and the northern stream
shortwave, is still resulting in a fair amount of uncertainty
regarding the timing/track and intensity of the low even with the
event now just over two days away. This in turn results in
continuing uncertainties with the specifics of some of the hazards.

As a result of the lingering uncertainty, elected to maintain the
High Wind Watch for now across Long Island, Brooklyn, and Queens.
Regardless of the ultimate advisory vs. warning decision, expect a
strong gradient to set up between the high to the north and the
approaching coastal low. This will result in a period of strong
gusty winds beginning midday Sunday and continuing through much of
the day on Monday. The strongest winds are expected Sunday night
through Monday morning, with gusts 50-55 mph across Long Island, and
30-40 mph elsewhere. The potential still exists for a few gusts to
60 mph, particularly across the Twin Forks and immediate south shore
of Long Island. Winds will gradually begin to decrease Monday
afternoon.

Rain chances will continue to increase Sunday morning as the coastal
system approaches from the south and continue through the day on
Monday. Anywhere from about 2 to 3 inches of rain is expected during
this time, highest at the coast. Given the long duration of the
rainfall and dry antecedent conditions, expecting this to primarily
be a beneficial rainfall, although can`t completely rule out some
minor nuisance flooding in typically flood-prone areas.

Winds will continue to diminish Monday night into Tuesday as the
system gradually begins to pull away from the coast. Conditions will
gradually begin to dry out north and west of the city, although
shower chances will linger through much of the day Tuesday across
Long Island and southeastern Connecticut.

While exact timing and track of the impacting coastal storm will
need to be resolved, by mid next week, the general synoptic picture
has the system exiting further out into the Atlantic. Broad and weak
high pressure attempts to build across the Great Lakes in its wake,
ushering in a cooler and drier air mass into late week.

Much drier air filters in on Wednesday in the subsequent northerly
flow, and winds may remain breezy with a tightened pressure gradient
between the exiting low and building high, before this should begin
to slacken by Thursday. PWATs fall toward or under half an inch by
Wed night or early Thursday with the cool, dry flow. With the drier
air, a cooler air mass comes with it, and temperatures fall from the
mid to upper 60s on Wednesday, down into the upper 50s and lower 60s
for Thursday and Friday.

While the steadiest precipitation and most active of the weather
exits, rain chances persist at times through the period. Some global
guidance is signaling additional shortwave energy moving through and
could bring additional rain chances into late week.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
As one area of high pressure retreats to the east through
Saturday, another area will build to the north across eastern
Canada. At the same time, low pressure will begin to take shape
off the southeast coast

Expect mainly VFR conditions through the overnight, then
ceilings lowering to MVFR, mainly during the afternoon hours
Saturday. Pockets of light rain may impact the terminals late
tonight into Saturday, before increasing in coverage Saturday
night. Confidence in light rain Saturday is too low to mention
in the TAFs at this time.

SE-S winds less than 10 mph this evening are expected to become
light and variable overnight as winds begin to respond to low
pressure to the south. Expect E/SE winds on Saturday to increase
to 10 to 15 mph with gusts up to 20 mph at the coast. Expect
gusts to hold off until Saturday night for inland areas.

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

Chance of MVFR as early as 12Z Saturday with pockets of light
rain moving in off the ocean. Low confidence in MVFR.

.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...

Saturday afternoon through Saturday night: Chance of rain with
MVFR, mainly Saturday night. NE winds G20-25kt late.

Sunday and Monday: Rain. MVFR cond expected, IFR cond possible
in bands of heavier rain, mainly at the coastal terminals.
Isolated thunderstorms possible Sunday night into Monday at the
coastal terminals. NE winds 20-30kt, G35-45kt at KISP, 15-25kt,
G30-40kt at the NYC metro/CT terminals, and G20-30kt at KSWF.
LLWS possible with about 50 kt at 2,000 feet for all terminals
except KSWF.

Tuesday: MVFR to start with a chance of showers, possibly
improving to VFR during the afternoon. N to NNE winds sustained
at 10-15kt, G20-25kt.

Wednesday: VFR.

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

&&

.MARINE...
Sub-SCA conditions expected on all waters today through much of
Saturday. Winds will start increasing Saturday night ahead of a
developing coastal storm. Gales remain possible on the ocean
especially overnight. A gale watch remains in effect.

A Storm Watch remains in effect on all waters except for New
York Harbor Sunday through Sunday night with the potential for
gusts of 45-50 kts as a strong gradient sets up between an
approaching coastal low and high pressure to the north. Winds
should weaken below storm force during the day on Monday, but
expect gale conditions to continue through at least Monday night
and possibly into the day on Tuesday on the ocean waters as the
coastal low is slow to pull away from the region. For New York
Harbor, a Gale Watch remains in effect with gale conditions
expected Sunday through much of the day on Monday before gusts
gradually diminish below 35 kt.

Seas of 8-10 ft on the ocean Sunday morning will increase to 15-20
ft Sunday night into the day on Monday before subsiding Monday night
into Tuesday. On the Long Island Sound, seas will peak at 4-8 ft on
the central and western Sound and 10-14 ft on the eastern
Sound.

Winds and seas will continue to lower Wednesday as low pressure
exits the region, and sub advisory conditions are expected to
return to all waters by Wednesday night.

&&

.HYDROLOGY...
Widespread rainfall of 2 to 3 inches is expected Saturday night
through Monday. While minor nuisance/poor drainage flooding is
possible, no significant impacts are expected with this being a
long duration rainfall and the recent dry conditions.

No additional hydrological concerns are expected mid to late next
week.

&&

.TIDES/COASTAL FLOODING...
Total water levels are expected to approach and possibly just
meet minor coastal flood benchmarks this morning`s high tide
cycle for the Nassau County south shore bays and S Fairfield.
Impacts should be minimal.

The potential remains for widespread moderate to locally major
coastal flooding and beach erosion Sunday and Monday, via the
combo of high astronomical tides and surge generated by strong
NE flow. Breaking waves around 8 to 12 ft possible based on 20+
ft seas offshore. A Coastal Flood Watch remains in effect for
the entire coast.

Current forecast has isolated locations in the south shore back
bays in Nassau and locations in the far western Great South Bay
exceeding major flood stage. While Stevens came in a bit higher
than ETSS and ESTOFS at these locations, there was enough
agreement of potential 3 to 4 foot surge to have the confidence
to forecast major. There is still a bit of uncertainty however,
especially in timing, as the guidance used for this forecast
leans more towards the GFS and Canadian surge timing of late
Sunday night into early Monday morning. The ECMWF brings in the
stronger winds closer to Monday and Monday night. This trend
will have to be monitored and can result in high tide cycles
beyond Monday being more of a concern.

There was decent disagreement across the CT coast, with Stevens
coming in much lower than the ETSS and ESTOFS. This could be a
result of small wind direction differences as a more northerly
wind would likely result in a lower flood threat. For now have
minor flooding across the CT coast.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Coastal Flood Watch from Sunday afternoon through Monday
     evening for CTZ009>012.
NY...Coastal Flood Watch from Sunday afternoon through Monday
     evening for NYZ072-074-075-079-081-178.
     Coastal Flood Warning from 2 PM Sunday to 8 PM EDT Monday for
     NYZ071-073-078-176-177.
     High Wind Watch from Sunday afternoon through late Sunday
     night for NYZ075-078>081-176>179.
     Coastal Flood Warning from noon Sunday to 6 PM EDT Monday for
     NYZ080-179.
NJ...Coastal Flood Watch from Sunday afternoon through Monday
     evening for NJZ006-104-106-108.
MARINE...Storm Watch from Sunday morning through late Sunday night for
     ANZ331-332-335-340-345-350-353-355.
     Gale Watch from Sunday morning through Monday afternoon for
     ANZ338.
     Gale Watch from Saturday evening through late Saturday night
     for ANZ350-353-355.

&&

$$

SYNOPSIS...FEB/DR/DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...FEB/DR
AVIATION...DW
MARINE...FEB/DR/DW
HYDROLOGY...FEB/DR/DW
TIDES/COASTAL FLOODING...