FXUS61 KOKX 251149

Area Forecast Discussion
National Weather Service New York NY
749 AM EDT Sat Sep 25 2021

A stationary front will remain east of the region through the
weekend. A weak area of low pressure will develop along the front
and pass southeast of the area tonight. High pressure then builds
over the area Sunday and Monday. A weak cold front moves across the
region on Tuesday. High pressure will then move in to the north as
the front stalls to the south. Low pressure may develop to the south
by the end of the week.


Forecast on track this morning with just a minor adjustment to
include some patchy fog north of NYC. Otherwise, a stationary
front will remain east of the region today with weak high
pressure to the west. Aloft, a closed upper low will dig towards
the Great Lakes, with a trough extending down to the Gulf
coast. This axis becomes negatively tilted towards the
Northeastern US tonight.

As this trough approaches the region, a weak low will develop along
the stalled front and could bring some rain to the far eastern
sections of the forecast area, mainly eastern Suffolk, NY and New
London and Middlesex counties in CT. Precipitation chances increase
tonight as the weak low passes southeast of the region. Have bumped
POPs up to likely for a period between 06z and 12z. A few of the
showers may produce some brief moderate to locally heavy rainfall.
Rainfall totals will generally range between a half and one inch.

Across the remainder of the area, mainly dry conditions are expected
with weak high pressure west of the area.

Highs today will be in the 70s with lows tonight falling into the
50s and lower 60s.


Surface high pressure dominated the weather pattern on Sunday and
Monday as a surface low pressure system spins well to the north.
Much of the area looks dry and comfortable with highs in the low to
middle 70s both days.


Not making any significant changes to the long term. With much
uncertainty, especially late in the forecast period, have decided
to stick close to the NBM guidance.

The long-term pattern is dominated by an upper-level trough
that sits over the Northeast getting reinforced by mid-level
disturbances. This will result in a low confidence and potentially
unsettled timeframe.

A low pressure system to the north sends a weak cold front into the
area from the NW by Tuesday. This cold front gets additional energy
from a mid-level shortwave by the time it moves south of the area
into early Wednesday, which may result in a wave of low pressure
developing along it.

In the mid-levels, a deepening trough over the area greatly
amplifies a ridge over the center of the country which extends into
the Hudson Bay region of Canada. A shortwave dives into the area
straight from the north which reinforces the trough over the
Northeast and prevents the ridge from progressing eastward.
This reinforcement in the mid-levels likely forces a low
pressure system to develop to the south of the area along the
stalled front. A strengthening high pressure system to the north
forces the low pressure to retrograde back westward into the
Mid-Atlantic coast. This forces an anticyclonic wave break over
the area with a large cut-off low pressure positioned over the
East Coast and a strong high pressure system to the north. While
the exact strength, timing, and placement of these features
remains uncertain, all global models show some depiction of

As a result of this pattern, there will be a chance for showers on
Tuesday with the cold frontal passage, and then mainly along the
coast from the development of a coastal low from Thursday and
through the beginning of the weekend. With a N/NE flow through much
of the period, temperatures will be at or slight below average with
highs in the middle 60s to low 70s for much of the extended period.


There will be a stalled front east of Long Island today. Low
pressure will move north along the stalled front tonight.

Mainly VFR conditions are expected through the TAF period. There
will be likely be a period of MVFR with rain showers for KGON
and perhaps KISP and KBDR as well late tonight.

Winds will be near NE-N direction and near 5 kts this morning.
Sea breezes are expected in the afternoon near 7-9 kts. Winds
become more W-NW at night, and for some terminals will decrease
to near 3-5 kts and become variable in direction.

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

Timing of sea breeze on Saturday may be 1-3 hours off.

.Sunday...Becoming VFR east of NYC terminals. VFR elsewhere. NW
winds 10-15 kt with gusts up to 20 kt during the day.
.Monday...VFR. SW winds 10-15 kt with gusts up to 20 kt during
the day.
.Tuesday...Possible MVFR in showers.
.Wednesday...Mainly VFR.

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


Sub-SCA conditions are expected to continue through tonight. Long
period 4-ft SE swell may work into the waters Sat night from distant
subtropical storm Teresa, located N or Bermuda.

SCA or near SCA conditions are then expected to develop on Sunday
through Tuesday morning with seas near 5 feet and gusts near 25 kt.
Sub-SCA conditions return Tuesday and Wednesday. Ocean seas are
expected to reach SCA levels once again late this week.


No hydrologic impacts expected attm. Rainfall amounts tonight across
eastern Long Island and Eastern Connecticut will range between a
half and one inch.


Expect a moderate rip current risk for the ocean beaches for today
with residual SE swells of 3 to 4 ft and 7 to 8 sec period. A
moderate rip current risk is also expected for Sunday and could
potentially be a high rip current risk as SE swells will be around 4
ft and could at times build to 5 ft with period increasing to 9 to
10 sec.





NWS OKX Office Area Forecast Discussion