Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 251052

Area Forecast Discussion
National Weather Service New York NY
652 AM EDT Mon Sep 25 2023

The remnant low of Ophelia drifts east today getting to the south
and east of Long Island this afternoon. The low will then continue
to drift south and east further offshore tonight into Tuesday as
high pressure gradually builds south out of eastern Canada. The high
should take control Tuesday night into Wednesday, but there is a
chance that a coastal front backs up toward the area late in the


Low pressure remains to the south today, drifting east of the NJ
coast, then southeast as high pressure continues to build into the
region from eastern Canada. The latest guidance shows rain and
shower activity lingering across the region. HREF PMM continues to
show the more focused forcing across interior sections for much of
today, before starting to translate further east and weakening to a
degree as it does so. The higher QPF should fall across the Lower
Hudson Valley and east into portions of SW CT where an additional
inch or so of rain is likely, with lesser amounts across far eastern
CT and points south for NYC and much of Long Island, especially
along the south shore. The gusty easterly winds continue through
tonight, however the rain will begin to get lighter from north to
south as any forcing weakens further. Skies will remain cloudy with
a rather small temperature range due to gusty winds and cloud cover.
Therefore temperatures will average below normal today by around 10
degrees or so, but average near normal tonight. Any shower activity
tonight should be rather light with amounts under a quarter inch,
and perhaps closer to a tenth of an inch tonight, mainly across
southern portions of the area.


For Tuesday the last of the shower activity should be pivoting
through southern portions of the area in the morning, and likely
pushing south of Long Island in the afternoon hours. Breaks in the
overcast develop across northern sections in the morning, and work
its way further south during the late afternoon hours. With a gusty
ENE wind continuing and clouds attempting to hang in look for
temperatures once again to average well below normal, with mainly
lower half of the 60s.

By Tuesday night high pressure makes its push further south out of
Eastern Canada. Skies will clear from north to south during the
evening hours, with some clouds lingering across far southern
sections perhaps into early Wed morning. Temperatures will actually
fall closer to normal much cooler 40s across the interior, with
lower 50s along the immediate coast. The gusts should end on a
lighter ENE wind as the pressure gradient weakens.


There is general consensus at the start of the period that low
pressure south of the region will track far enough south and
east that there will be a period of dry weather for the mid
week. However, there is uncertainty with respect to an upper
low/trough undercutting the ridge that progresses towards the
end of the week and whether or not it amplifies enough to draw
the offshore low and associated frontal system back toward the
East Coast, as well as how far north. Thus, there are low rain
chances in the forecast Thursday through Saturday, then drying
out on Sunday. This forecast though looks to very much be in
flux with run to run changes likely in how this is handled.

There should be some sun during the mid week period with an
general NE to ENE flow continuing, albeit weaker. Sunshine and
dry conditions becomes less certain based on the aforementioned
coastal front for the end of the week.

Temperatures during this period will generally be several
degrees below normal, with high in the middle and upper 60s and
lows in the 40s and 50s. Forecast highs warm to around 70 at
weeks end.


Low pressure lingers south of the region during the TAF period.
High pressure starts to build in late in the TAF period from
the north.

Rain will be intermittent throughout much of the TAF period.
There will also be fog present to keep visibilities lower.
Mainly IFR conditions are expected with slight improvements
slowly taking place from north to south late this afternoon and
into tonight, mainly for KSWF and CT terminals. Rain will
lessen towards the latter half of the TAF period as well.
Confidence is low on the timing of improvement to MVFR.

Winds NE around 10-15 kt will increase to around 15-18 kts
through the remainder of the TAF period. Gusts develop after
12-13Z today near 20-25 kt and continue for much of the
remainder of the TAF period. There could be some occasional
gusts up to 30 kt for the daytime into evening.

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

There could be some fluctuation between MVFR and IFR.

Gusts to 30 kt could occur occasionally today into this evening.

Brief localized LIFR will be possible at times.

End time of IFR could be a few hours off from TAF.

The afternoon KJFK haze potential forecast is YELLOW...which implies
slant range visibility 4-6SM outside of cloud.

The afternoon KLGA haze potential forecast is YELLOW...which implies
slant range visibility 4-6SM outside of cloud.

The afternoon KEWR haze potential forecast is YELLOW...which implies
slant range visibility 4-6SM outside of cloud.


Tuesday: Possible MVFR/IFR and rain showers morning into early
afternoon. Otherwise, VFR. NE wind gusts near 20 kt. Gusts
eventually subside at night.

Wednesday: VFR. Some daytime NE wind gusts 15-20 kt.

Thursday-Friday: Chance of rain showers. MVFR possible. Some NE wind
gusts 15-20 kt mainly during the daytime.

Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/


Strong and gusty northeast to east winds will continue through
Monday night and into much of the day Tuesday as the remnant low of
Ophelia moves and remains to the south of the forecast waters as
high pressure gradually builds south out of eastern Canada. Small
craft conditions on the near shore waters have been extended through
the day on Tuesday, along with gales out on the ocean waters. Gusts
on the nearshore waters will get to or just above 30 kt, with gusts
out on the ocean waters of 35 to 40 kt. By Tuesday afternoon the
stronger gusts will dissipate, with sub small craft gusts and sub
gale gusts conditions possibly ending.

A persistent ENE flow will continue through the week, albeit a
weaker flow. Seas out on the ocean will remain elevated with small
craft seas continuing.


Additional rainfall of up to an inch is likely through today
across the Lower Hudson Valley and portions of SW CT. Otherwise,
the remainder of the region will likely see a quarter to a half
inch of additional rainfall. Hydrologic concerns are unlikely
as the storm system gradually weakens and also pushes east and
away from the areas which have seen the most rain.


Persistent E-NE flow this week an an approaching full moon will
result in increasing astronomical levels and extra surge,
thereby resulting in multiple rounds of coastal flooding this
week. Mostly minor coastal flooding is expected although some
localized moderate coastal flooding is expected in the Peconic
Bay near Riverhead.

Around 1.5 to 2 ft of surge is needed for minor coastal flooding
across the Lower NY Harbor, South Shore Bays and Eastern Bays of
Long Island as well as the SW CT and Southern Westchester NY
shoreline of Western Long Island Sound. These locations have
coastal flood advisories in effect from late this afternoon into
this evening and are expected to have multiple locations
experience minor coastal flooding with particularly Peconic Bay
in Riverhead getting some localized moderate coastal flooding.
For Upper NY Harbor, rest of Long Island and NYC shorelines
along Long Island Sound as well as Southern New Haven CT, there
are coastal flood statements in effect for late this afternoon
into this evening. The coastal flood statements cover where
minor coastal flooding will be more localized or isolated.

A high risk of rip currents will remain in effect through Tuesday
evening. Seas build today with an easterly swell once again
increasing to around 9 seconds late today and this evening.
The surf increases throughout today with 4 to 7 ft breaking waves
tonight and into Tuesday. The surf will likely start to subside
gradually late Tuesday night into Wednesday. Held off on surf
advisory issuance for now with the expectation of averaging just
below surf advisory criteria.


CT...Coastal Flood Advisory from 6 PM to 11 PM EDT this evening for
NY...Coastal Flood Advisory from 6 PM to 11 PM EDT this evening for
     Coastal Flood Advisory from 3 PM this afternoon to 8 PM EDT
     this evening for NYZ074-075-178-179.
     High Risk for Rip Currents through Tuesday evening for NYZ075-080-
     Coastal Flood Advisory from 5 PM this afternoon to midnight
     EDT tonight for NYZ079>081.
MARINE...Small Craft Advisory until 6 PM EDT Tuesday for ANZ331-332-335-
     Gale Warning until 6 PM EDT Tuesday for ANZ350-353-355.



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