882
FXUS61 KOKX 161823
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
223 PM EDT Fri Aug 16 2024

.SYNOPSIS...
Weak high pressure remains in place through tonight. A weakening
low pressure system then slowly approaches from the Great Lakes
this weekend. A warm front then lifts through early Monday as
the center of the low redevelops near or over the region. The
associated cold front passes through later Monday, with a
secondary frontal passage into Tuesday. High pressure then
builds in behind the system for mid to late next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Only minor changes for current conditions with this update.
Patchy haze, 6SM, being report across the lower Hudson Valley
and interior southern Connecticut, as lower stratus mixes out.
Also, potential for some smoke, especially later this afternoon.

Surface high pressure will be accompanied by ridging aloft. The
combination of the two will keep us dry today, and with still
enough of a ridge aloft tonight, we should be able to get
through the night without any showers. Can`t rule out a slight
reduction in surface visibility this afternoon mainly NW of the
city as per the HRRR smoke forecast, but not enough confidence
to include in the forecast. Just expect a hazy appearance of the
sky outside of cloud cover. NBM looked good for temperatures
through tonight, and dewpoints will be a little higher than what
they were yesterday, so it should feel a little more muggy.
Patchy fog possible tonight, primarily over CT and eastern LI.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY/...
Low pressure slowly tracks east and weakens across the Great Lakes
this weekend. A leading warm front approaches, but is progged to
remain west of the forecast area through at least Sunday afternoon.
With the slow eastward progression of the system, shower chances
will also slowly advance east across the area during Saturday.
Likely PoPs don`t begin until late Saturday night, and are probably
limited to west of around the Hudson River during Sunday. Eastern
portions of LI and CT may end up dry for the entire period. Thunder
possible starting Saturday afternoon, but isolated in nature until
perhaps Sunday afternoon when chances over the western zones
increase.

PWATs increase, and chances of at least minor flooding begin to
increase Sunday afternoon, mainly over NE NJ and adjacent areas of
the Lower Hudson Valley. This will be when more efficient rains
could occur as the convective threat increases, and lift is enhanced
by both an increasing low level jet and the left-exit region of an
upper jet streak in the vicinity. See the hydrology section
below for more details. NBM was used for temperatures through
the period.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
An approaching upper level trough, with a frontal system on the
leading edge, shifts into the Northeast early next week. A warm
front lifts through Sunday night into early Monday, with guidance
indicating the development of a secondary low which passes near or
over the region Monday morning. The attendant cold front tracks
through later in the day, with perhaps a secondary front Monday
night or early Tuesday.

Two primary periods of precipitation from this system look to
develop Sunday night into early Monday with the warm front, then
additional activity along and ahead of the cold front later Monday.
Parameters appear rather tame in terms of severe weather from this
system, relatively low instability and shear, though increased
moisture with the SW flow will allow locally heavy downpours that
could lead to nuisance flooding at times. A subsequent NW flow
develops behind it Tuesday, ushering in a much drier air mass.
Surface high pressure begins to build in from the Midwest into
midweek and should allow relatively dry and tranquil conditions,
though the lingering trough aloft could support additional cloud
cover in cyclonic flow.

Temperatures look to average near, if not slightly below, normals
for mid to late August, with highs generally into the upper 70s to
around 80, and lows falling back into the 50s and 60s. The national
blend was largely followed for this update, with only subtle
adjustment.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
Weak high pressure remains in control through tonight with a
warm front approaching on Saturday. Showers increase from west
to east in the afternoon and early evening with chances of tstms
increasing after 20-22z.

VFR forecast.

Light southerly winds remain through Saturday with speeds
remaining at or under 10 kt.

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

Timing of onset of precip may be off by an hour or two.

OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...

Saturday Night: MVFR or lower conditions possible in showers/tstms.

Sunday and Monday: MVFR or lower in SHRA/TSRA.

Tuesday: Mainly VFR. MVFR or lower possible in any SHRA/TSRA in the
afternoon....mainly eastern terminals.

Wednesday: VFR.

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

&&

.MARINE...
No changes to winds and seas at this time.

Sub-advisory conditions on all waters today. Seas then begin to
increase tonight and into the weekend with energy from distant
Hurricane Ernesto reaching the coast. Please refer to NHC for
official forecasts regarding Hurricane Ernesto. Waves will
largely be 5-7 feet Friday night through the weekend. Small
Craft Advisories are in effect for all the ocean zones beginning
tonight and lasting through Sunday. SCA conditions likely
persist on the ocean waters through Monday night with elevated
swells up to 8 ft. These should lower by late Tuesday, with sub
SCA conditions then expected on all waters thereafter.

&&

.HYDROLOGY...
Rainfall from Saturday night through Monday is expected to range
from around a half inch to an inch for a good portion of the area,
however amounts could ramp up towards 2 inches NW of the city in a
relatively short distance. Given some uncertainty as to where this
tight gradient sets up, confidence isn`t very high regarding the
flash flooding potential. Considering that the higher amounts would
more likely occur over areas typically more prone to flash flooding
(portions of NE NJ and adjacent areas of the Lower Hudson Valley), a
marginal to slight risk of flash flooding exists. Best guess right
now is that any impacts would not start until Sunday afternoon at
the earliest, and would more likely happen any time from Sunday
night through Monday night. Can`t rule out flash flooding elsewhere,
but any flooding impacts would be more in the minor category.

No hydrological concerns follow thereafter through late next
week.

&&

.TIDES/COASTAL FLOODING...
There will be a high rip current risk today, mainly in the afternoon
into early evening. This high risk then continues through Saturday
and likely lasts through the entire weekend. This is due to SE
to S long period swells from Hurricane Ernesto. Please refer to
NHC for official forecasts regarding Hurricane Ernesto.

Ocean seas are forecast to be highest Sunday into Monday, with
heights up to 8 feet. There is potential for high surf along the
ocean beaches during this timeframe as well as beach erosion. In
addition, the high risk of rip currents will likely extend through
early next week.

Minor coastal flooding is possible early next week during high tide
cycles Sunday through Tuesday as swells build and astronomical tides
increase due to the full moon on Monday.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents through Saturday evening for NYZ075-080-
     081-178-179.
NJ...None.
MARINE...Small Craft Advisory from 10 PM this evening to 6 PM EDT
     Sunday for ANZ350-353-355.

&&

$$

SYNOPSIS...JC/DR
NEAR TERM...JC/MET
SHORT TERM...JC
LONG TERM...DR
AVIATION...20/DR
MARINE...JC/DR
HYDROLOGY...JC/DR
TIDES/COASTAL FLOODING...