000
FXUS61 KOKX 252011
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
411 PM EDT Mon Mar 25 2024

.SYNOPSIS...
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A strong high pressure ridge over the area will gradually weaken
through Tuesday night, giving way at first to a maritime flow
around an ocean storm, and then to a weakening cold front
approaching late Tuesday night into Wednesday. Low pressure will
develop along the Atlantic seaboard on Thursday, eventually
tracking into the Canadian Maritimes over the weekend.
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&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
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NE flow between the inland ridge and an offshore storm will
gradually diminish this evening. Meanwhile, moistening in the
H8-9 layer above a sfc-based inversion should lead to an
increase in low clouds, affecting SE CT and ern Long Island at
first toward midnight, then spreading eastward to most of the
rest of the CWA overnight. Low temps tonight will range from
25-30 inland NW of NYC (a few degrees below normal), to the
lower 30s most elsewhere, to the mid 30s in/just outside NYC
(both near normal).
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&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
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Shallow moisture trapped under an inversion keeps us cloudy
through this time frame. Weak lift arriving from the east also
introduces slight chance of some light rain or drizzle over Long
Island and S CT mainly in the afternoon on Tue, then spreading
to the rest of the CWA with PoP increasing to 30-40%.

High temps in the maritime environment on Tue will be well below
normal, only in the 40s, while nighttime temps Tue night will be
a couple of degrees above normal.
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&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
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Residual light rain and dz is expected on Wed. The models are
attempting to clear it out during the 2nd half of the day, but
this may be a case where the wetter NAM in the llvls is the
better soln. With weak wind fields in place and no strong lift
to produce pcpn, have kept the dz in the fcst all day except for
the extreme wrn portion of the cwa.

Wed ngt and Thu include a good deal of uncertainty despite the
fairly short time horizon. This is due to the upr trof and
pcpn chances ahead of the main low. This event, per the 12Z
models, resembles a pre minus the tropical moisture, with a
chance of a corridor of rain ahead of the main low. Timing of
this is Wed ngt into Thu, followed by more rain with the main
sfc low which should develop invof the Carolinas Thu and pass E
of the cwa Thu ngt into Fri. A round of rain is likely with this
main low, putting aside any large track deviations to the
right. Timing is centered on Thu and Thu eve. The consensus NBM
has about a 80-90 pop for most of the cwa, ern areas favored.
Stuck with these numbers for the fcst.

Winds on the back side of the sys develop Fri. With the track
and timing uncertainty comes the wind uncertainty as well. The
operational GFS is slower than the GEFS mean. Slower generally
equates to deeper in this case, with the slowest ensemble
members dropping the low around 975 SE of Cape Cod on Fri. The
mean at this time however has the low near downeast ME. CONSALL
was used for winds which brings a NW flow around 15-25 mph with
gusts around 35 mph, but there is room for upward adjustment.

If the storm wraps up further S, there could be some snow before
the sys exits. Right now this is a low prob, but if a 970s low
E of ACK materializes, would expect to see some snow in at
least portions of the cwa.

The flow flattens out over the weekend into Mon, but there is
still a chance for some bouts of rain with any energy embedded
in the flow. Low pops per the NBM, but the 12Z GFS is dry, and
the 12Z ECMWF is dry until late Mon.

The NBM was used for temps with minor adjustments.
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&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
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High pressure this evening slowly retreats through tonight.

VFR early tonight, with MVFR cigs moving in from east to west early
Tuesday morning. IFR patches in the morning with wider coverage re-
developing late in the day or evening hours. Spotty light rain or
drizzle not out of the question Tue but coverage not great enough to
include in TAF. Better chance of drizzle Tue evening onward.

Northeast winds around 10kt this evening. Gusts around 20kt with the
best chances at the eastern coastal terminals. Gusts likely continue
tonight for KBDR, KISP and KGON. Less confident in gusts west of
these terminals tonight. Gusts diminish somewhat overnight into
Tuesday.

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

Low confidence in gusts tonight and Tuesday. Will likely be more
occasional.

Amendments possible late tonight into early Tuesday morning with
MVFR cigs moving in. IFR possible eastern terminals but coverage
is uncertain.

OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...

18z Tuesday: MVFR with a chance of light rain/drizzle especially
later in the day. Chance of IFR late in the day and at night.

Wednesday: MVFR/IFR with a chance of light rain and drizzle.

Thursday: MVFR/IFR with rain likely.

Friday: MVFR with chance of rain...becoming VFR. Gusty Winds
possible aft.

Saturday: VFR with NW Gusty winds to 30kt 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 remains in effect for all but NY Harbor and the
western/central Sound per latest obs showing NE flow gusting
25-30 kt near shore or at some of the offshore buoys. and seas
6-9 ft at the buoys, and likely 5-6 ft on the non ocean waters E
of Orient. These conds likely to persist into this evening on
the bays of Long Island. Persistent NE flow on the ocean and
far ern Sound likely to last into Tue morning, then winds there
should gradually diminish Tue afternoon and night, with seas
following suit Tue night.

Light winds Wed and Thu, then increasing winds Thu ngt and Fri.
Seas on the ocean 3-5 ft on the ocean Wed and Thu. Gales are
possible on Fri. SCA will be needed on the ocean Sat, and will
be possible elsewhere.
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&&

.HYDROLOGY...
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Potential for hydrologic impacts late Wed night into Fri with a
general 1-3 inches of rain possible. Some higher amounts will be
possible depending on how the sys develops.
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&&

.TIDES/COASTAL FLOODING...
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The combination of high astronomical tides and swell/tidal
piling should bring multiple rounds of minor coastal flooding
the the high tide cycles tonight into Tue night. Advisories
remain in effect for the high tide cycle tonight and daytime Tue
for S Nassau and also S Fairfield/Westchester where water
levels will be well into the minor category, with statements
most elsewhere as water levels tough or approach minor
thresholds. Only exception will be along the SE CT coast and NE
Suffolk where water levels most likely fall short.

Forecast based on the higher of the bias-corrected Stevens
NYHOPS 50th percentile and a Stevens/ETSS blend, which both do
well in these types of situations.

Tue night could be a repeat performance. Did not lower water
levels from model fcst as was done with the previous forecast
as these types of events actually tend to hang on for at least
one high tide cycle longer than fcst.
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&&

.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...Coastal Flood Advisory from 11 PM this evening to 2 AM EDT
     Tuesday for CTZ009.
NY...Coastal Flood Advisory from 11 PM this evening to 2 AM EDT
     Tuesday for NYZ071-073-176-177.
     Coastal Flood Advisory from 8 PM to 11 PM EDT this evening for
     NYZ072-074-075.
     Coastal Flood Advisory from 9 PM this evening to 2 AM EDT
     Tuesday for NYZ080.
     Coastal Flood Advisory from 8 PM this evening to 1 AM EDT
     Tuesday for NYZ178-179.
NJ...Coastal Flood Advisory from 8 PM to 11 PM EDT this evening for
     NJZ006-106-108.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ331-
     340-345.
     Small Craft Advisory until 6 PM EDT Tuesday for ANZ332.
     Small Craft Advisory until 6 AM EDT Wednesday for ANZ350-353-
     355.
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&&

$$

SYNOPSIS...BG/JMC
NEAR TERM...BG
SHORT TERM...BG
LONG TERM...JMC
AVIATION...IRD
MARINE...BG/JMC
HYDROLOGY...JMC
TIDES/COASTAL FLOODING...BG