Area Forecast Discussion
Issued by NWS Upton, NY

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236
FXUS61 KOKX 231956
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
356 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/...
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.

&&

.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 /20Z MONDAY THROUGH SATURDAY/...
High pressure remains in control today.

Mainly VFR conditions into much of tonight. Cigs are forecast
to lower back to MVFR or close to it Tue morning mainly after
12Z.

E-NE winds around 10 kt, with some brief gusts 15-18 kt, should
veer more to the E and diminish to under 10 kt this evening,
then back NE overnight.

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

Ocnl G15-18kt possible this afternoon.

OUTLOOK FOR 18Z TUESDAY THROUGH FRIDAY...

Tuesday afternoon: VFR. NE-E winds around 10 kt. Ocnl G15-20kt
possible.

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

Wednesday night: Chance of showers with MVFR 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

&&

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

Small Craft Advisory remains in effect on the ocean waters through
Tuesday night, though an extension is likely as ocean seas remain
elevated Wednesday 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...
The offshore low responsible for the easterly swell that has
helped pile water into the area will work slowly southeast
through early this week and bring an end to the widespread
coastal flooding after high tide this afternoon. No changes were
made to the ongoing headlines currently in place.

The most vulnerable locations in the south shore back bays,
particularly in southern Nassau, may see brief minor coastal
flooding with high tide Tuesday afternoon. 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 Tuesday afternoon. No
additional issues are anticipated beyond that time.

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

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Coastal Flood Advisory until 6 PM EDT this evening for CTZ009.
NY...Coastal Flood Advisory until 6 PM EDT this evening for NYZ071.
     High Risk for Rip Currents through Tuesday afternoon for NYZ075-080-
     081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EDT Wednesday for ANZ350-353-
     355.

&&

$$

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