discussion on 2024-03-25

000
FXUS61 KOKX 251415
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1015 AM EDT Mon Mar 25 2024

.SYNOPSIS...
-- Changed Discussion --High pressure over the area early this week will give way to a
weakening cold front moving through during Wednesday night.
Strengthening low pressure will then pass offshore to the south
and east Thursday night into Friday, followed by weak low
pressure approaching from the west this weekend.-- End Changed Discussion --

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --The forecast remains on track. Minor adjustments made to trend
from latest obs.

High pressure ridges in from the NE. Somewhat brisk, mainly at
the coastal areas, with NE winds. Mostly sunny today, except for
some cirrus filtering the sun across eastern Long Island and SE
CT. High temps around 50. Low level moisture then advects in
from the east with low clouds increasing overnight.-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
-- Changed Discussion --Shallow moisture trapped under an inversion keeps us cloudy
Tuesday through Wednesday. Weak isentropic lift arriving from
the east introduces a slight chance of light rain or drizzle
over LI and southern CT starting Tuesday afternoon. This threat
then increases and spreads west to the rest of the forecast area
Tuesday night into Wednesday. Moisture will be deepening west
to east on Wednesday ahead of a cold front. Threat of rain
therefore trends higher towards the western zones on Wednesday,
but capped PoPs at 50%. Also expecting areas of fog starting
Tuesday night when the turbulent mixing potential near the
bottom of the low level inversion lessens. We could be stuck
with the fog well into the day Wednesday with light winds and
plenty of low level moisture.

High temperatures slightly below normal on Tuesday, then milder
on Wednesday with widespread 50s.-- End Changed Discussion --

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
-- Changed Discussion --A weakening cold front will pass through Wednesday night, which
will bring the potential for some light rain. A wave of low
pressure will develop farther south along the boundary as an
upper level trough approaches. The low will strengthen quickly
south and east of the area with the upper level trough becoming
negatively tilted. This feature will bring light to moderate
rain to the area Thursday into Thursday night, with the higher
chance for moderate rain across the eastern half of the area.
Guidance is in decent agreement showing higher rainfall amounts
for the eastern half of our area. See hydrology section below.

The low will slowly exit to the northeast and keep the pressure
gradient over the area tight. Expect gusty NW-W conditions
Thursday night through Saturday, with periods of 30 to 35 mph
gusts.

A quick moving shortwave trough approaches behind the departing
system along with associated weak surface low. Moisture and
lift are limited, with the higher values just southwest of the
area. Stuck with slight chance PoPs Saturday into Saturday
night.

High temperatures wont vary too much through the long term
period. Highs will be right around or above normal, in the
50s.-- End Changed Discussion --

&&

.AVIATION /14Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --High pressure this afternoon slowly retreats through tonight.

VFR through tonight, with MVFR cigs moving in from east to west
early Tuesday morning.

Northeast winds this afternoon, with speeds increasing along
the coast. Gusts around 20-25kt expected this afternoon with
the best chances at the coastal terminals. Gusts likely continue
tonight for KBDR, KISP and KGON. Less confident in gusts west
of these terminals tonight.

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

Gusts mainly 20-25 kt today. Higher confidence at KJFK and
KLGA, but may be more occasional at KEWR and KTEB. A few higher
gusts are possible.

Lower confidence in gusts tonight. Will likely be more
occasional.

Amendments possible late tonight into early Tuesday morning with
MVFR cigs moving in.

OUTLOOK FOR 12Z TUESDAY THROUGH FRIDAY...

Tuesday: MVFR with a chance of light rain/drizzle. 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.

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

&&

.MARINE...
-- Changed Discussion --SCA for all but NY Harbor and the western Sound today as a
tighter pressure gradient and stronger winds will be generally
over the eastern half of the waters. There may be occasional
gusts to 25 kt for these two zones, but not enough to go with a
SCA.

Winds drop off a little tonight, more so over most of the non-
ocean waters, but should occur more slowly than previously fcst,
so extended the SCA for the central waters to 06Z tonight.
Given elevated seas due to swell entering from the east,
extended the SCA over the eastern Sound through Tuesday.
Gusts to 25 kt also still possible through at least tonight and
perhaps into a part of Tuesday.

SCA on the ocean has been extended through Tuesday as well for
gusts and/or elevated seas due to swell. A gust or two to gale
force cannot be ruled out over the far eastern ocean waters
today, but not enough to upgrade to a gale warning. SCA on the
ocean will likely need to be extended into Tuesday night and
perhaps even Wednesday as swell keeps seas elevated.-- End Changed Discussion --

&&

.HYDROLOGY...
-- Changed Discussion --Light to moderate rain is possible Thursday from NYC north/west,
and moderate to locally heavy rain across Long Island and most
of S CT. Earlier NBM probabilities showed about a 70% chance of
1 inch of rain and 30-40% chance of 2 inches for Long Island
and S CT. Blend of 06Z GFS and 00Z ECMWF/Canadian in agreement
with this. Given propensity for storms to trend slightly west of
model fcsts several days out, rainfall of up to an inch
throughout and up to 1.5" in NYC not out of the question.
Given this will fall over a 24-36 period, there are no
hydrologic concerns attm.-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
-- Changed Discussion --The combination of high astronomical tides and swell/tidal
piling is expected to bring a round of widespread minor
coastal flooding with tonight`s high tide cycle, and the
potential of additional widespread minor flooding with both
daytime and nighttime high tide cycles on Tuesday.

For tonight, advisories have been issued from the south shore
back bays of SW Suffolk County westward through NY Harbor.
Advisories are also in effect for a large portion of western
Long Island Sound. There is even a chance that moderate flooding
thresholds are briefly touched for southern Nassau and Queens.
Finally, statements have been issued for SE and NW Suffolk
county, where flooding is expected to be only isolated.

The forecast for tonight was based heavily on what would be
approximately the 65th percentile of Stevens Institute NYHOPS,
which was overall higher than an even blend of ESTOFS, ETSS
and 50th percentile NYHOPS. A downward adjustment for both of
Tuesday`s cycles was made with some uncertainty in the amount of
tidal piling occurs after tonight`s first round of flooding,
and at least in the case for Tuesday daytime, the astronomical
tides will be lower than tonight`s. Additional minor flooding
will nevertheless still be possible for both of Tuesday`s cycles
with the highest confidence of occurrence across southern
Nassau and Queens and lower NY Harbor.-- End Changed Discussion --

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
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 ANZ332-350-353-
     355.

&&

$$

SYNOPSIS...JC/BG
NEAR TERM...JC/BG
SHORT TERM...JC
LONG TERM...JT
AVIATION...JT
MARINE...JC/JT/BG
HYDROLOGY...JC/JT/BG