discussion on 2023-08-26

000
FXUS61 KOKX 262034
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
434 PM EDT Sat Aug 26 2023

.SYNOPSIS...
-- Changed Discussion --A cold front approaching from the lower Great Lakes will cross the
area tonight. High pressure then builds in from the north and west
on Sunday and gradually weakens and moves offshore to start the
week. A stationary front northwest of Tropical Cyclone Franklin,
which will stay well south and east of the area, briefly backups
toward the east coast Monday and into Tuesday. At the same time,
a cold front approaches from the northwest, passing across the
area Wednesday morning. High pressure builds in for the end of
the week. Another potential tropical system may pass to the
south off the Carolinas late in the week.-- End Changed Discussion --

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --Quiet conditions tonight as a secondary cold front moves
southward pushing drier air across the region. With the latest
CAMs backing down on the development of any showers across the
area through this evening have gone with a dry forecast for the
rest of tonight.

Lows tonight will be in the upper 50s to mid 60s.-- End Changed Discussion --

.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
-- Changed Discussion --High pressure starts to build in from the north and west behind the
departing secondary cold front Sunday morning. Although heights rise
slightly aloft, the mean upper level trough remains over the
northeast. Dry conditions are expected on Sunday.

High temperatures will be just below normal on Sunday, in the
mid 70s to lower 80s. With a stronger flow out of the east on
Monday and more sky cover, highs will be 3-5 degrees cooler.-- End Changed Discussion --

.LONG TERM /MONDAY THROUGH SATURDAY/...
-- Changed Discussion --High pressure centered north of the area to start the week will
gradually weaken while retreating offshore. At the same time, a
stationary front well north and west of TC Cyclone Franklin will
start to edge north and west as a warm front Monday night into
Tuesday. Around the same time frame, Tropical Cyclone Franklin
is expected to lift north in the Western Atlantic. The system is
progged to stay well offshore with no direct impacts. However,
some indirect impacts will be dangerous rip currents due to an
increasing swell and high surf, especially Tuesday and Wednesday.

There is some uncertainty with the extent of the rain shield
Monday into Tuesday as the front interacts with mid-latitude
jet energy as an upper trough amplifies across the Great Lakes.
The latter of which will also send a cold front toward the
region. For the time, have maintained low chances Monday night,
which gradually increase through Tuesday. With an easterly
flow, airmass remains fairly stable, so any embedded thunderstorms
look isolated late Tuesday. This will depend on how far the
offshore warm front gets to the area. The ECMWF was the northernmost
solution with some heavier rainfall getting into portions of
eastern LI and SE CT. However, the 12Z run has backed off some,
but still bring about half to one inch to these areas, with
lesser amounts north and west. The GDPS (Canadian) and GFS are
more suppressed with generally a quarter of an inch or less.
This seems to hinge on the amplitude of the incoming upper
trough and the placement of the upper jet along the eastern
side. The ECMWF maintains a somewhat more amplified system with
with a more favorable position of the RRQ of the upper jet.
Right now, leaning toward a lighter rainfall solution based on
latest trends in guidance.

Behind the frontal boundary look for a cP air mass with cooler
temperatures and comfortable conditions into the later half of next
week. Temperatures will be near normal with leftover humidity on
Wed, followed by cooler temperatures and noticeably lower humidity
with dew point reading in the 50s by Thursday.

High pressure will be in control with dry conditions Thursday
and Friday. Another tropical system may pass to the south off
the Carolina coast late in the week.

Monitor https://www.weather.gov/okx/tropical or http//www.nhc.noaa.gov
for the latest NHC forecasts on this tropical system and
others.-- End Changed Discussion --

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
In the wake of a cold frontal passage, high pressure builds
gradually late today and tonight.

VFR conditions will prevail for the remainder of the TAF
period. There is a low chance of sub-VFR conditions for outlying
terminals late tonight into early Sunday.

Generally light 10 kt or less N winds through the TAF period,
though winds may become light NE or NW. Afternoon seabreezes
are possible at coastal terminals this afternoon and tomorrow
afternoon.

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

No unscheduled amendments expected through the TAF period.

OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY...

Sunday: VFR.

Monday: VFR, with MVFR/IFR and shra possible at night.

Tuesday: MVFR or lower in SHRA, especially in the afternoon and
evening.

Wednesday: MVFR or lower with shra or tsra possible.

Thursday: VFR

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

.MARINE...
-- Changed Discussion --Sub-SCA conditions are expected through Monday night as high
pressure builds in. However, a SE swell being supplied by
Tropical Cyclone Franklin increases and becomes more energetic
into Tuesday and Tuesday night. Small craft conditions develop
by Tuesday afternoon with ocean seas expected to climb to 5 to 6
ft, and perhaps to 8 ft further east Tuesday night into
Wednesday. Seas will begin to gradually diminish late in the day
Wednesday as high pressure builds in from the northwest and
Franklin heads farther out into the western Atlantic. SCA seas
are likely linger into Thursday.-- End Changed Discussion --

.HYDROLOGY...
There are no hydrologic issues through next week at this time.

.TIDES/COASTAL FLOODING...
-- Changed Discussion --There is a high risk for rip current development for all but the
NYC beaches (moderate) through this evening due to 3 to 5 ft
southerly wind waves. A gradually building ESE swell on Sunday
will likely produce moderate risk for the LI beaches.

Swells from tropical cyclone Franklin will likely build late Monday
into Tuesday, continuing into midweek, increasing likelihood for
high surf and dangerous rip currents. In addition, a full moon on
Wed Night will have astro tides increasing through the mid to late
week period. Combined with the high surf, the potential for areas of
ocean beach erosion/flooding and scattered areas of dune erosion
increases during the times of high tide Tue/Wed.-- End Changed Discussion --

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents until 8 PM EDT this evening for NYZ080-
081-179.
NJ...None.
MARINE...None.