000
FXUS61 KOKX 190909
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
409 AM EST Sun Nov 19 2023

.SYNOPSIS...
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A cold front approaches today and moves across tonight. Strong
high pressure from the Great Lakes then builds in through
Monday night. High pressure moves offshore Tuesday, followed by
a complex frontal system and associated low pressure for
Tuesday night into early Wednesday. High pressure builds for
Wednesday night through Friday. Low pressure may approach next
weekend.
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&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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A cold front will approach from the northwest today. Ahead of
the cold front, vertical mixing is expected to be efficient,
resulting in a breezy day. Temperatures will be climbing well
into the 50s along the coast and within NYC as well as Northeast
NJ. Downsloping with the NW flow will allow for this temperature
gradient between coast and more inland locations.

Clouds increase late day but did not mention rain showers as
sounding profiles show much dry air.
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&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
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A cold front moves across. Gusty winds continue with increased
cold air advection.

Strong high pressure builds in for Monday and Monday night. Much
cooler temperatures expected Monday and Monday night with cold
air mass within the region.

Winds decrease Monday with light to calm winds Monday night as
pressure gradient weakens.
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&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
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The main feature of the long term period will be a complex
frontal system and associated low pressure that is expected to
impact the region late Tuesday and Tuesday night, into early
Wednesday.

On Tuesday an upper ridge will be moving off the east coast as
a deep upper trough moves through the Upper Midwest and
Tennessee Valley. The upper trough will be progressive and swing
across the eastern states Tuesday night into Wednesday morning.
The biggest uncertainty is the energy in the SW states and how
much of that energy gets involved in the trough as it swings
east and into our area. The GFS gets more of the SW US energy
involved, while some of the other global guidance does not and
hangs much of the SW energy back to the west, and thus the
system deamplifies as it progresses through towards mid week.
These details will be important in ultimately determining how
potent this storm system will be, and the impacts for our area.

Meanwhile, the primary low will lift northeast and up the
Tennessee and Ohio Valleys, while a secondary will form likely
in the Mid Atlantic towards the Delmarva and track nearby and
just south or east of the region. With the high pushing offshore
and a return flow out of the SE and off the warmer ocean,
expect precip to be mainly plain rain at the onset, although a
few wet flakes at the start cannot be ruled out well N and NW. A
strong surge of warm advection in the lower and mid levels is
expected with the NAM and GFS suggestive of a strong LLJ and
frontogenetic forcing. The LLJ at 925 mb may reach 50 to 60 kts
with strong isentropic lift along the warm front and PWATs
increasing to around over an inch Tuesday night, with periods of
moderate to heavy rainfall possible. While the system will be
progressive, 1 to 1.5 inches of rainfall is a good possibility,
with locally higher amounts of up to 2 inches. Progs show
little elevated CAPE and little instability however at this
time. WPC has placed SW portions of the area in a marginal risk
of excessive rainfall.

The system is expected to get offshore by Wed afternoon as
drier air comes in. The GFS with its more robust and slightly
trailing upper level feature tries to spin up a double barrel
south to north low, but there is little support from the other
models camps. As low pressure moves away and deepens offshore a
northwest flow will usher in drier air. Afterwards, the
uncertainty increases for late in the week as most of the global
models indicate more southern branch energy into the Gulf and
SE states. The Canadian continues to advertise a system coming
out of the Gulf and deep south with low pressure bringing rain
to the region as the low tracks along the eastern slopes of the
Appalachians and hugs the coast on Friday. While the GFS and
German guidance continues to hold energy back until late Sat and
Sat night with possible low pressure emerging from off the SE
coast and it lifts north and offshore, with runs of the European
being in-between the Canadian and the GFS/German guidance.
These timing difference all have to do with the handling of
southern branch energy. The results are varying outcomes in
terms of the sensible weather for the tail end of the week.

In summary, after rain and wind for late Tue into early Wed,
look for clearing and drier conditions late Wed into the
Thanksgiving holiday. Uncertainty then increases for Friday into
Saturday. After above normal temperatures for late Tue into
Wed, look for temperatures to fall back to near normal on
Thanksgiving, and slightly below normal for late in the week.
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&&

.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
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High pressure will be in control through the TAF period.

VFR conditions expected to prevail through the TAF period.

West winds generally 4 to 6 kts. WNW winds 10-15kt develop this
morning with gusts around 20kt in the afternoon. Peak gusts to
near 25 kt late this afternoon into this evening.

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

Start time of more frequent gusts today may be 2-4 hours
earlier than forecast.

OUTLOOK FOR 09Z MONDAY THROUGH THURSDAY...

Monday: VFR.

Tuesday: VFR AM. Chance MVFR and rain late afternoon. SE gusts
around 20 kt in the afternoon.

Tuesday night: IFR and rain. SE gusts around 30kt possible. LLWS
possible toward the early Weds AM morning push with SE winds 40-50kt
at 2kft.

Wednesday: IFR/MVFR with rain likely early. Bcmg VFR in the
afternoon with W-NW gusts around 20kt possible.

Thursday: VFR. NW gusts around 20kt possible.

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

.MARINE...
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SCA continues on the ocean with sub-SCA conditions on non-ocean
waters today. The ocean SCA has been extended into Monday
morning. SCA has also been hoisted for non-ocean waters tonight
with 25 kt gusts expected for much of the tonight time period.
For Monday, ocean SCA could hold on into afternoon but
confidence is low on wave forecast and wave heights could be off
by 1-2 ft so did not want to extend too much with ocean SCA.
Otherwise, non-ocean waters expected to be below SCA Monday. All
waters expected to be below SCA Monday night.

A east flow becomes southeast and increases Tuesday in advance
of a complex frontal system and associated low pressure. Small
craft conditions will arrive either later in the day or by
evening and through at least Tuesday night, and likely into the
Wednesday. A period of gales cannot be ruled out, especially on
the ocean waters and eastern nearshore waters Tuesday night and
Wednesday morning. Behind the frontal system the winds will
switch to the northwest for Wednesday afternoon and Wednesday
night. The NW flow will continue into Thursday with marginal
small craft conditions likely persisting on the ocean, and
possibly for a portion of the nearshore waters.
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&&

.HYDROLOGY...
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Mainly dry conditions are forecast through Tuesday with no
hydrologic impacts expected.

Moderate to heavy rain is likely Tuesday night into early
Wednesday morning, with minor and nuisance flooding possible.
There is the potential for 1 to 1.5 inches of rainfall, with
locally higher amounts up to 2 inches possible. WPC has placed
southwestern portions of the area in a marginal risk of
excessive rainfall for this system.
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&&

.TIDES/COASTAL FLOODING...
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While astronomical tides remain relatively low into the beginning of
the week, an increasing southeast flow Tuesday afternoon and Tuesday
night ahead of a frontal system will allow forecast surge to
increase quickly. Local to widespread minor coastal flooding is
becoming more likely for portions of the coastline during the
Tuesday night/early Wednesday morning high tide cycle. Statements
and advisories will likely be needed for portions of the coast. The
highest likelihood of reaching minor coastal flood benchmarks are
for the south shore bays of Nassau and SW Suffolk, but also a good
portion of the CT coast along with Lower Westchester and some
sections of the north shore of Long Island, and possibly Peconic
Bay. The winds will switch quickly offshore during the day
Wednesday, thus at this time subsequent high tide cycles are
expected to fall short of minor coastal flood benchmarks.
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&&

.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 3 PM this afternoon to 6 AM EST
     Monday for ANZ331-332-335-338-340-345.
     Small Craft Advisory until noon EST Monday for ANZ350-353-355.
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&&

$$

SYNOPSIS...JE/JM
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...JE
AVIATION...JM
MARINE...JE/JM
HYDROLOGY...JE/JM
TIDES/COASTAL FLOODING...