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618
FXUS61 KOKX 240255
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1055 PM EDT Mon Sep 23 2024

.SYNOPSIS...
High pressure remains in place along the Northeast coast through
Tuesday. A frontal system moves through the region Wednesday through
Thursday. High pressure builds to the north Friday and then remains
into the beginning of next week.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
-- Changed Discussion --
The forecast is generally on track. Added patchy drizzle or
sprinkles overnight with some light returns showing up on radar
and KHPN reporting drizzle.

High pressure centered over coastal southeast Canada is nosing
down along the Northeast coast and remains in place through this
evening.

A weak shortwave passing north in the flow has been helping to
instigate some light rain showers and sprinkles, mainly west of the
Hudson River this afternoon. This activity is dissipating as it
attempts to work west into the surface ridging and a dry sub
cloud layer. Given this, total QPF should remain under a tenth
of an inch everywhere, with the bulk of southern CT and LI
remaining entirely dry.

Any lingering rain dries up by the late evening hours, leading to a
dry overnight. Cloud cover remains though, and temperatures
bottom out in the 50s and lower 60s across the region.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
Surface ridging strengthens along the Northeast coast on Tuesday,
helping keeping conditions largely dry. Off to the west, an
incoming upper trough amplifies across the Midwest and Central
US.

The pattern will continue to offer varying levels of cloud cover
during the day, with afternoon temperatures peaking around 70,
or just a few degrees below normal for late September. Light
onshore flow around the surface high persists.

Into Tuesday night, the upper ridge axis begins to shift east,
with the flow splitting ahead of the advancing trough, helping
to limit a more substantial moisture feed into the region.
Weak WAA well ahead of the associated incoming warm front over
the Mid Atlantic begins overnight into Wednesday. While much of
the night appears dry, not entirely out of the question far
western areas see a few sprinkles or rain showers before
daybreak Wednesday.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Key Points:

* Showers possible Wednesday through Thursday with the passage
  of a frontal system.

* An extended period of dry weather returns Thursday night and
  continues into the beginning of next week.

A northern stream trough moves across the northern tier Wednesday
into Thursday as a surface frontal system passes through the
northeast, with the center of the low passing across southern
Canada. A warm front moves through Wednesday night into early
Thursday. There is some very weak forcing and elevated CAPE with the
passage of the warm front and have now included isolated convection.
The best forcing with the passage of the cold front Thursday will be
to the north and have chance probabilities and no mention of thunder.

A strong ridge builds into the eastern states Friday and remains
into the beginning of next week, bringing another extended period of
dry weather. With an Omega pattern setting up one closed upper low
moves across eastern Canada into the western Atlantic, and another
closed low remains nearly stationary over the Plains and the
Mississippi Valley.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
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High pressure remains in control today.

Mainly VFR conditions tonight. Some guidance is pointing to a
brief period of high end MVFR ceilings that move across Long
Island sound tonight and into northeast NJ that could impact
KLGA, KHPN, KEWR, and KTEB, mainly after 03Z for HPN after 06Z
for the metro terminals. Since KHPN is currently reporting MVFR
as of just before 03Z, this increases the certainty for the
previously mentioned terminals to see MVFR overnight as well.
Drizzle or sprinkles are also possible overnight, but should not
limit visibility.

Thereafter, generally VFR expected through Tuesday, though
there may be brief periods that ceilings lower MVFR ceilings.
KISP may see prevailing MVFR ceilings late Tuesday morning.
Thereafter, MVFR ceilings are not expected until Tuesday night.

E-NE winds around 10 kt or less overnight and increase to around
10 kt during the day Tuesday. Winds shift more toward the E late
in the day Tuesday. An occasional gust of 15 to 20 kt is
possible during the late morning into the early evening hours
Tuesday.



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

Unscheduled amendments possible due to changing flight
categories. Ceilings are expected to be low end VFR/high end
MVFR through much of the TAF period, so there is uncertainty in
ceiling forecast.

OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...

Tuesday night: MVFR or lower. E winds around 10 or kt less.

Wednesday: Chance of showers with MVFR or lower cond from the
NYC metros north/west, otherwise VFR.

Wednesday night: Chance of showers with MVFR or lower cond
throughout, but mainly after midnight at KISP/KGON. Slight
chance of a tstm in the evening from the NYC metros north/west.

Thursday: Chance of mainly morning showers/MVFR cond, otherwise
VFR.

Friday and Saturday: VFR.

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

&&

.MARINE...
Elevated long period swells from a slow departing offshore low
pressure will continue into late in the week.

With high confidence in ocean seas remaining elevated through
Wednesday have extended the Small Craft Advisory until 600 PM
EDT Wednesday. Another extension of the SCA is possible as seas
remain elevated through Thursday, and possibly into Thursday
evening. With the passage of a cold front late Thursday into
Thursday night, winds shift to the northwest and ocean seas fall
below SCA levels. Once seas fall below 5 feet conditions will
remain tranquil into the upcoming weekend.

&&

.HYDROLOGY...
There are no hydrologic concerns through this weekend.

&&

.TIDES/COASTAL FLOODING...
High tides have passed this evening and water levels were below
the minor flooding benchmarks at all coastal locations.
Additional brief minor coastal flooding is possible at the most
vulnerable locations in the south shore back bays Tuesday
afternoon, particularly in southern Nassau. The back bays can
be slow to drain which has occurred in similar past events, so
have gone closer to Steven`s guidance for locations such as East
Rockaway, Reynolds Channel, and Freeport. A coastal flood
statement may eventually be needed for these locations for the
Tuesday afternoon high tides. No additional issues are
anticipated beyond that time.

The high risk of rip currents continues through Wednesday
evening with offshore low pressure still bringing long period
E/SE swells.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents through Wednesday afternoon for NYZ075-
     080-081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT Wednesday for ANZ350-353-
     355.

&&

$$

SYNOPSIS...DR/MET
NEAR TERM...JP/DR/MET
SHORT TERM...DR
LONG TERM...MET
AVIATION...JP
MARINE...DR/MET
HYDROLOGY...DR/MET
TIDES/COASTAL FLOODING...