000
FXUS61 KOKX 182312 CCA
AFDOKX
Area Forecast Discussion...CORRECTED
National Weather Service New York NY
712 PM EDT Mon Sep 18 2023
.SYNOPSIS...
-- Changed Discussion --
A low pressure system pushes away tonight. High pressure builds
Tuesday and remains in control through Friday before shifting
off the New England coast Friday night into the weekend. Low
pressure may impact the region Saturday and Sunday.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Deepening low pressure system just offshore lifts north and east
this evening, as an upper trough tracks through the region. A
broad area of mainly steady light rain, mainly north and east of
the center, will continue to push into southern New England and
out of the local region. Behind it, more intermittent showers
persist into the latter portion of the evening across mainly
eastern and far northern sections until drier air is able to
work in tonight. Additional rainfall amounts should largely
remain under a quarter inch, except perhaps across southern CT
where enhanced jet dynamics with the incoming trough may help
overcome the relatively weak mid level lapse rates and produce
locally heavy downpours.
Temperatures overnight generally bottom out in the 50s with
dew points dropping more noticeably after 6z. Parts of the
urban metro should hang closer to 60. At this point, thinking
the winds should stay up enough to preclude the formation of
fog, but will have to be watched in case winds underachieve
for a couple of hours across interior / rural locations later
tonight.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/...
Drier conditions return into midweek as low pressure exits and high
pressure enters. The H5 trough axis overhead early Tuesday lifts
north and east, allowing for gradual height increases through
Wednesday as ridging builds in. This will lead to a more tranquil
pattern the next couple of days.
An increased pressure gradient between the departing low and
building high will elevate the flow a bit Tuesday. Northwest winds
10 to 15 mph with a few gusts 20 to 25 mph early in the day should
lighten by late afternoon. Other than a bit of fair weather cu,
sunshine prevails. With the boundary layer mixing to around 800 mb
per BUFKIT soundings, temperatures should be around normal for mid
September, with highs generally in the mid 70s Tuesday.
A similar tale on Wednesday, with surface high pressure to the west
maintaining the northerly flow and dry air mass. Abundant sun
can be expected with little cloud cover during the afternoon
hours.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
There has been no significant change to the long term and have
largely followed the NBM during the period.
Deterministic models and ensemble means are in good agreement with
the larger scale pattern into the upcoming weekend. Ridging aloft
will build over the northeast Wednesday night through Friday. As a
result, high pressure will be in control with tranquil conditions
for the end of the week. At the same time, southern stream energy
will undercut the ridge and form a broad trough over the southeast.
High pressure both aloft and at the surface begin to shift offshore
this weekend. The modeling has continued to trend towards an
organized low pressure developing along or off the southeast coast
Friday into Saturday. To the north of the low, an inverted trough
appears to set up as the surface high moves off the New England
coast.
The models diverge on the timing, placement, and strength of the
aforementioned low pressure. However, trends are beginning to signal
that moisture will increase from south to north this weekend. The
ensembles show varying solutions with regard to the evolution of the
track of the low pressure with some lifting it northward Saturday
towards the Middle Atlantic while others hold it near or over the
southeast into Sunday. These differences are handled well within the
model consensus. PoPs have been increased a bit this weekend, but
still remain in the chance category. The NBM probabilities of
greater than 1" in any 6 hour period this weekend remain low and
less than 10 percent. These values have been similar over the last
several cycles. Unsettled conditions are possible this weekend with
potential for a soaking, longer duration rainfall event.
Temperatures through the period look seasonable, but could end up
slightly below average during the upcoming weekend with more clouds
and potential rainfall.
&&
.AVIATION /23Z MONDAY THROUGH SATURDAY/...
An area of low pressure moves east of the region tonight. High
pressure builds for the remainder of the TAF period.
MVFR and IFR for the next few hours for eastern most terminals,
otherwise VFR conditions prevail throughout the period. KGON will
be the last terminal to go to prevailing VFR towards 4-5z. Before
then cannot completely rule out some brief LIFR for KGON until 3z as
any rain showers taper off and end out east.
The winds transition to more of a NW direction tonight. Wind speeds
into Tuesday increase to near 10-15 kt. A few gusts near 15-20 kt
are possible tonight. More frequent gusts to near 20-25 kt are
expected on Tuesday, generally in the late morning and afternoon.
Gusts will end early Tue evening.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Brief MVFR ceilings are possible before 2z, otherwise no amendments
expected.
OUTLOOK FOR 0Z WEDNESDAY THROUGH SATURDAY...
Tuesday night: VFR with winds light to calm.
Wednesday - Friday: VFR.
Saturday...MVFR possible with a chance of rain showers. E gusts near
15-20 kt.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
An increasing northwest flow develops tonight behind departing
low pressure, and gusts on the ocean waters may be near 25 kt
at times. In addition, southeast swells will be increasing from
distant Hurricane Nigel, with ocean seas reaching SCA levels,
thus a small craft advisory has gone into effect across the
ocean waters. The seas will remain elevated through Tuesday,
and possibly into Tuesday evening before lowering. A Small Craft
Advisory will remain in effect for these waters into Tuesday.
Swells could linger into Wednesday, and seas may be near SCA
levels east of Moriches Inlet.
Winds on the waters should remain below SCA levels Wednesday
through Friday. A steepening pressure gradient then brings
increasing winds and potential for SCA gusts, especially on the
ocean on Saturday. Elevated seas are possible on Thursday with
E-SE swells from Nigel. Seas may also become elevated above 5
ft on Saturday to the north of low pressure near the southeast
coast.
Monitor https:/www.weather.gov/okx/tropical or
https:/www.nhc.noaa.gov for the latest NHC forecasts on Hurricane
Nigel.
&&
.HYDROLOGY...
Localized nuisance flooding will be possible in heavier downpours
into this evening.
No hydrologic impacts are anticipated Tuesday through the end of
the week. Uncertainty exists in the timing and amounts of
potential rainfall for the upcoming weekend.
&&
.TIDES/COASTAL FLOODING...
There is a high rip current risk for all Atlantic-facing
beaches on Tuesday given 3 to 5 ft swells with 8 to 10 second
periods.
This should begin to lower on Wednesday, with a moderate risk in
place for all beaches.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents from 6 AM EDT Tuesday through Tuesday
evening for NYZ075-080-081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT Tuesday for ANZ350-353-355.
&&
$$
SYNOPSIS...DR/DS
NEAR TERM...JE/DR
SHORT TERM...DR
LONG TERM...DS
AVIATION...JE
MARINE...DR/DS
HYDROLOGY...DR/DS
TIDES/COASTAL FLOODING...