000
FXUS61 KOKX 191806
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
206 PM EDT Tue Sep 19 2023

.SYNOPSIS...
High pressure builds into the region and remains in place through
Friday. High pressure shifts to the northeast of the area late
Friday into Saturday. A low pressure system may then impact the
region Saturday into early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Pleasant September afternoon with a bit of a breeze at times.
Visible satellite and local cameras highlight some fair weather
cu, but conditions remain dry regionwide through tonight. Forecast
remains on track and previous discussion follows. A closed low
H5 trough axis shifts east of the region today with rising
heights as ridging develops. The tightened pressure gradient
between departing surface low pressure and a building high is
allowing for a bit of an elevated flow. West northwest winds
around 10 to 15 mph with a few gusts 20 to 25 mph can be
expected through the afternoon, gradually lightening this
evening. Temperatures top out in the lower and middle 70s under
a bit of fair weather cu and plenty of sunshine.

Tonight, as the the high builds closer to the area, clear skies
and lighter winds should allow for efficient radiative cooling
conditions to set up. Coastal and urban areas fall into the
50s, and the usual cooler spots well north and west of NYC and
the Long Island Pine Barrens can expect temperatures in the 40s.
-- End Changed Discussion --

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Surface high pressure will remain over the region through the short
term with mostly sunny skies both Wednesday and Thursday. A
Northwest flow on Wednesday and more of a northerly flow on Thursday
will keep conditions really pleasant with high temperatures in
the lower and middle 70s both days.

Wednesday and Thursday nights temperatures will once again fall into
the 50s with a few spots reaching the 40s.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Global models and their respective ensemble system have a general
agreement on the synoptic pattern into the weekend, though
differences do exist in the handling of a late week system with
southeast origins. The ridging in that was in place over the
northeast during the week begins to weaken and move offshore by
Friday. At the same time, a slow, nearly cutoff upper low
originating over the Carolinas pushes slowly north and is somewhat
impeded by the ridging in place over the northeast. This upper low
remains across the northeast for much of the period resulting in
unsettled weather from the weekend into early next week.

With respect to sensible weather, dry conditions are expected under
subsidence and retreating surface high pressure Friday into early
Saturday. Some late day clouds may begin to overspread the area
Friday afternoon in advance of surface low pressure well to the
south of the local area.

Thereafter, a surface low begins to take shape off the southeast
coast and heads northeast into the weekend. There are differences in
the strength, track, and timing of this feature in the guidance, with
some maintaining the ridge to the northeast effectively suppressing
the track of the low to the south of the area keeping it dry. Others
track the system over the area, or just to the east, bringing a
plume of high PWAT air with it, resulting in a long period of
precipitation Saturday through Sunday, along with gusty winds. In
addition, some guidance, particularly GEFS members, is indicating an
inverted trough associated with the main sfc low approaching as
early as Saturday morning with an additional slug of precipitation at
the onset. Global ensemble (GEFS, CMCE, ECE) means, and thus the NBM
all paint about 1-1.5" Saturday into early Monday for the area, but
the spread in individual ensemble members is quite large. NBM
probabilities of >1" in any 6 hour period through Sunday remain
quite low at this time, less than 10% continuing over the past few
cycles. WPC has introduced a marginal risk of excessive rainfall for
Saturday. Details should come into better view over the next few
days with additional guidance sources available for that time horizon.

Ridging then looks to try and nose down from New England by Monday
afternoon, potentially clearing and drying out the area. Seasonable
temperatures are forecast for the period, though clouds and rain
over the weekend may allow for slightly cooler conditions.

&&

.AVIATION /17Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
VFR.

High pressure builds over the terminals for the TAF period.

WNW winds at 10-15 kt with gusts around 20 kt this afternoon
will quickly diminish early this evening as winds back to the NW
at less than 10 kt. Winds will then back further to the WNW on
Wednesday at 7-10kt, possibly becoming WSW in the afternoon at
the coastal terminals.

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

Winds will be mainly left of 310 magnetic through early this
evening, then veer to the right.

OUTLOOK FOR 18Z WEDNESDAY THROUGH SATURDAY...

Wednesday Afternoon - Friday: VFR.

Saturday and Sunday: MVFR or lower likely in rain. E gusts
15-25 kt, possibly higher at the coastal terminals. Strongest
winds at this time look to be on Saturday.

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

&&

.MARINE...
-- Changed Discussion --
A tightened pressure gradient will continue to allow for occasional
25 kt gusts, particularly on the ocean, into this evening before
lowering. In addition, southeast swells from distant Hurricane Nigel
are leading to 5 to 7 ft, thus a small craft advisory remains
in effect across the ocean waters. The seas will remain elevated
through this evening, before lowering tonight. Swells could
linger into Wednesday, and seas may be near SCA levels east of
Moriches Inlet.

Winds on the waters should remain below SCA levels Wednesday
through Thursday night. A steepening pressure gradient then
brings increasing winds and potential for SCA gusts, especially
on the ocean on Saturday into Sunday. Seas may also become
elevated above 5 ft on Saturday to the north of low pressure
near the southeast coast.


Monitor https:/www.weather.gov/okx/tropical or
https:/www.nhc.noaa.gov for the latest NHC forecasts on Tropical
Storm Nigel.
-- End Changed Discussion --

&&

.HYDROLOGY...
No hydrologic impacts are anticipated through Friday.

The potential exists for a widespread precipitation event this
upcoming weekend. WPC has placed most of the CWA in a marginal risk
of excessive rainfall on Saturday. However, there is uncertainty in
the timing and amount of potential rainfall with this system at this
time.

&&

.TIDES/COASTAL FLOODING...
There is a high rip current risk for all Atlantic-facing
beaches today due to 3 to 5 ft swells with 8 to 10 second periods.

This should begin to lower on Wednesday, with a moderate risk in
place for all beaches.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents until 9 PM EDT this evening for NYZ075-
     080-081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 11 PM EDT this evening for ANZ350.
     Small Craft Advisory until 6 PM EDT this evening for ANZ353-
     355.

&&

$$

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