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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 162154
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
554 PM EDT Tue Apr 16 2024

.SYNOPSIS...
High pressure builds in overnight. A slow moving warm front then
approaches from the southwest tomorrow and moves through the area
into Thursday. High pressure briefly builds in for Friday before
a cold front passes through Friday night into Saturday morning.
High pressure then follows from Saturday afternoon through
early next week.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
-- Changed Discussion --
Only minor adjustments made to some of the hourly forecast
elements with this update. The forecast is mainly on track.

Upper level ridging upstream is allowing for a surface high pressure
to build into the area tonight. This will result in fairly clear
skies with a light northerly flow. Any location that is able to
relax the wind a bit more, mainly outlying and inland areas, may
cool more than forecast. Cooler spots may drop into the upper 30s,
but much of the area should remain in the 40s with NYC near 50.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
The upper level ridge shifts overhead as the surface high
pressure shifts to the east tomorrow. A mid-level shortwave
moving over the Great Lakes allows a weakening surface low to
move into Southern Canada. The associated warm front approaches
the area from the southwest into the afternoon and evening and
will allow rain chances to increase due to deep-layer warm air
advection. While rain should be fairly widespread, especially
into the evening and overnight, much of the area should see
anywhere from 0.25" to 0.75" of rainfall, most of which should
fall tomorrow night and into early Thursday. While the rainfall
doesn`t appear to be convective in nature, some isolated
convective elements will be possible along with the low chance
of thunder, especially for southwestern areas into the evening
and overnight.

The rainfall will lighten up and showers should become more
widely scattered as the main area of forcing shifts south into
Thursday. Moisture will still be present and despite a lack of widespread
forcing, shower activity may continue into the day on Thursday,
progressively becoming lighter and less likely through the day.

An easterly flow and chances of rain will drop highs tomorrow about
5 to 10 degrees cooler than today, and this trend continues
into Thursday. East winds ramp up tomorrow night into Thursday
as the pressure gradient strengthens between the departing high
and the warm front. Gusts potential is 20 to 30 mph, highest
along the coast. A frontal wave developing along the warm front
pushes off the Mid Atlantic coast on Thursday.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
An inverted trough extending north from low pressure to our south
will linger near the forecast area Thursday night through Friday.
Moisture will be shallow during this time, but there could be just
enough isentropic lift in the vicinity of the trough for some
drizzle. Cloudy otherwise, with high temperatures in the middle to
upper 50s on Friday.

A cold front approaches and passes through Friday night into
Saturday morning. Moisture will deepen along with a chance of
showers with its passage. High pressure then builds in behind the
front with dry weather for Saturday afternoon. The high will
continue to build into the region through the rest of the weekend
and remain in control of the weather through Monday. High
temperatures near normal on Saturday, but cooling off slightly for
Sunday and Monday.

A 500mb trough then shifts through the Great Lakes on Tuesday with
an associated weak surface low. It appears that we should by dry
through the day, but cannot rule out a shower for western zones by
the end of the day.

&&

.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
High pressure remains over the terminals through tonight, then
weakens Wednesday as a warm front slowly approaches from the
southwest.

VFR through the TAF period. There is a low chance of MVFR ceilings
at the NYC metro terminals toward 18Z Wednesday, with low
confidence, and dependent on the timing of the warm front.

End timing of NW gusts may be an hour or so earlier than forecast. A
late day S/SW sea breeze remains possible at KJFK, as latest radar
data is showing the sea breeze south of KJFK.
Timing remains uncertain. Winds in the NYC metro area will be W to
NW less than 10 kt this evening, and may even become light and
variable, while the outlying terminals will likely become light and
variable this evening. Winds then become NE late tonight into early
Wednesday morning, and then E to SE. Timing of the wind changes late
tonight into Wednesday morning is uncertain and dependent on
weakening high pressure and warm front approach.

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

Gusts have become more frequent, and expected to end around 22Z.

The chance for a late day S-SW sea breeze remains possible for KJFK,
timing may be off by a couple of hours with confidence in occurrence
below average.

OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...

Wed afternoon and Thu: MVFR developing Wednesday afternoon with
showers becoming likely. Conditions lower to IFR, and possibly LIFR
at time with showers Wednesday night through Thursday.
Showers end with improving conditions Thursday night. Winds Thursday
east around 15kt with gusts 20-25kt, highest along the coast.

Fri: VFR early, then MVFR late day and at night with a chance of
showers.

Sat: MVFR with showers ending in the morning, becoming VFR.

Sun: VFR.


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

&&

.MARINE...
Wind and seas are forecast to remain below SCA as high pressure
builds in from the NW through tonight. A warm front approaches
on Wednesday with a tightening pressure gradient between the
front and departing high. There is the potential for SCA conditions
in an easterly flow late Wednesday night into Thursday. Gusts
of 25 to 30 kt will be possible with seas on the ocean of 4 to 7
ft.

Winds diminish Thursday night into Friday, however a lingering swell
with onshore flow may keep ocean seas above 5 ft through at least
Friday morning. Sub-advisory conditions on all waters otherwise
Friday afternoon through Sunday.

&&

.HYDROLOGY...
There is the potential for 0.25" to 0.75" of rainfall from
Wednesday afternoon through Thursday afternoon. No hydrologic
impacts are expected with this event.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$

SYNOPSIS...JC/MW
NEAR TERM...MW
SHORT TERM...MW
LONG TERM...JC
AVIATION...MET
MARINE...JC/MW
HYDROLOGY...JC/MW