Area Forecast Discussion
Issued by NWS Upton, NY

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663
FXUS61 KOKX 102353
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
753 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 /UNTIL 6 AM SATURDAY MORNING/...
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 /6 AM SATURDAY MORNING 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 /00Z SATURDAY THROUGH WEDNESDAY/...
High pressure off the New England coast retreats to the east
through Saturday as another high builds to the north across
eastern Canada. Meanwhile, low pressure will begin to develop
off the southeast coast, and begin to impact the area late
Saturday night.

VFR conditions through the overnight. There is a slight chance
of light rain at the NYC metro terminals late tonight. Then there
is a chance of MVFR ceilings late Saturday morning into late
afternoon with a chance of areas of light rain, except at KSWF
and KGON. Conditions become MVFR late Saturday afternoon, except
KSWF and KGON.

Light S winds become light and variable by late tonight remain
into Saturday morning. Then winds become E and 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 14Z Saturday with pockets of light
rain moving in off the ocean. Low confidence in MVFR, however,
did indicate with a PROB30. Gusts may begin a couple of hours
earlier, by 18Z.


.OUTLOOK FOR 00Z SUNDAY THROUGH WEDNESDAY...

Saturday night: MVFR with a chance of rain, becoming likely
late. 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...
Localized minor coastal flooding for the Saturday aft high
tides for the Nassau County south shore bays and S Fairfield.
Impacts should be minimal.

There is a high likelihood for widespread moderate coastal
flooding, with potential for localized major flooding, for the
Sunday aft and moreso Sunday Night high tide cycles along the
western Great South Bay as ENE-NE winds ramp up to marginal
storm force Sunday afternoon into Sunday Night. Confidence is
also high in areas of moderate coastal flooding along N and E
facing coastlines along Western LI Sound with combination of
water levels reaching marginal moderate flood levels, along with
3-6ft breaking wave action. Watches have been upgraded to
warnings for these areas.

Elsewhere for NY/NJ harbor, tidally affected rivers including
Hudson and Hackensack river, and along E LI coastal CT, a
widespread minor to locally moderate coastal flood threat
exists, which will be refined over the next 24 hrs. Coastal
flood watches remain for this area.

Potential exists for a similar coastal flood threat to continue
into the Monday aft/eve high tidal cycle, but some uncertainty
on how quickly wind backs from NE to N, and also how quickly
winds subside based on ultimate track and intensity of low
pressure. A blend of 75th percentile Stevens, and deterministic
STOFS and ETSS was used for this forecast.

Along the oceanfront, widespread dune base erosion and
localized overwashes are likely during the times of high tide
Sunday thru Monday, via the combo of high stormtide and breaking
surf around 8 to 12 ft. The prolonged e to w sweep will likely
result in considerable beach erosion (escarpment) as well. 4-8
ft surf along NE facing and open water exposed areas of the
twin forks of LI will also likely see minor to moderate dune
erosion.

&&

.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...MET
MARINE...FEB/DR/DW
HYDROLOGY...FEB/DR/DW
TIDES/COASTAL FLOODING...