000
FXUS61 KOKX 072349
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
749 PM EDT Mon Aug 7 2023
.SYNOPSIS...
A warm front moves through tonight, followed a cold front for
Tuesday, with high pressure building in for Tuesday night. High
pressure takes control on Wednesday, followed by a storm system
on Thursday. High pressure then returns for Friday and lasts
into at least part of Saturday before another system potentially
impacts us later in the weekend.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
-- Changed Discussion --
Warm front is through most of the forecast area as of early this
evening and will continue to head NE tonight. This occurring as
a shortwave shifts east into the area.
Adjusted PoPs upward into early this evening, mainly over some
of the southern zones as a line of showers and thunderstorms
over eastern PA is expected to hold together in a weakened
state. Some of these storms could become strong to severe, even
as it begins to move into western portions of the forecast area
CAMs continue show that this line will weaken as it moves
through the forecast area, primarily due to loss of instability
associated with daytime heating. Best chances of severe weather
will be over NE NJ, the Lower Hudson Valley and NYC, occurring
before midnight A sever thunderstorm watch is in effect for
these areas. The main threat will be gusty winds with a lesser
threat of large hail.
Another feature to watch is that the NAM Nest wants to develop an
area of showers and thunderstorms late tonight along a surface
trough or a weak area of low pressure, after 2 am that primarily
affects areas east of the Hudson. Kept chance POPs in for the
entire night, but did not go any higher due to uncertainty as
the NAM and certain runs of the HRRR are showing this.
Additionally, while heavy rain moved through portions of the
forecast area this morning, with radar estimates of over 2" in some
spots, enough time will likely elapse for this rain to have run off.
The line of storms looks to be progressive enough to preclude flash
flooding for much of the forecast area. However, flash flooding
cannot be totally ruled out, especially for NE NJ and NYC
where it takes less rain for flooding. An average additional 1/4
inch to an inch of rainfall is forecast across the area.
Locally heavier amounts are possible in any thunderstorms, with
PWATs over 2" noted in most models.
With dew points in the 70s, conditions will be warm and dry, with
overnight lows only dropping to the lower 70s.-- End Changed Discussion --
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
The upper shortwave trough axis moves east late in the day Tuesday
into Tuesday night as the cold front pushes offshore earlier in the
day. Low pressure well to the north of the area slowly strengthens.
With the trough still in the area, the chances for showers and
thunderstorms continues, but will not be as widespread as Monday,
nor as strong, as much of the dynamics should remain north and east
of the area.
With weak high pressure building late Tuesday into Tuesday
night, a drier air mass will be in place. Tuesday night will be
dry with dew points falling into the upper 50s to around 60.
Lows will be near normal for this time of year.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
The flow aloft becomes less cyclonic on Wednesday with weak high
pressure building in at the surface. This should be enough to keep
us dry through the day. Low pressure tracking through SE Canada then
drags a cold front toward the forecast area. This along with the
potential of a weak offshore low passing nearby brings chances of
showers and maybe a thunderstorm Thursday into Thursday evening.
High pressure returns for Friday with a dry day, then low pressure
emerging from the northern Great Lakes Region is progged to pass to
our north Saturday night into Sunday. This will bring a chance of
showers and thunderstorms mainly from Saturday afternoon through
Sunday evening. The flow aloft may then become slightly cyclonic on
Monday, bringing a diurnal threat of a shower or thunderstorm.
Temperatures through the long term period are expected to be near
normal with with high temperatures mostly in the lower and middle
80s.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
A warm front, moving through the region, lifts to the north
early this evening. A cold front then follows Tuesday morning
into the early afternoon.
Generally MVFR with brief periods of VFR before a line of
showers and thunderstorms moves through the terminals from
around 00Z through 04Z. Stronger to locally severe
thunderstorms are possible at the NYC terminals and west, with
the better chances across northeastern New Jersey. These storms
may quickly weaken as the line approaches the NYC terminals.
MVFR likely continues through the overnight, into Tuesday
morning, with scattered showers possible, and will continue
with the VCSH.
Gusty southerly winds continue ahead of the line of
thunderstorms, and gusts along the immediate coast may be more
occasional. Gusts with the storms may be as high as around 35
kt. With the passage of the line winds do back to the SW and may
be gusty at times. With the passage of the cold front winds
shift to a more westerly to NW directions and increase, with
gusts 20 to 26kt, and maybe occasionally higher through Tuesday
afternoon.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Uncertainty in timing and strength of thunderstorms through 02Z
with the potential for strong to severe thunderstorms.
Brief IFR cigs are possible after midnight. Improvement to VFR may
happen a few hours earlier on Tuesday afternoon.
OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
Tuesday night through Wednesday: VFR. W wind gusts around 20
kt.
Thursday: VFR.
Thursday Night-Friday: Mainly VFR. Chance of showers and MVFR. A
slight chance of thunderstorms Friday afternoon.
Saturday: Mainly VFR. Slight chance of afternoon showers and
thunderstorms mainly for NYC north and west.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
25 kt gusts expected on the ocean waters tonight as seas build
to near 5 ft. SCA in effect for the ocean tonight into Tuesday.
Mainly sub- SCA conditions remain elsewhere tonight going into
Tuesday but some waters will have occasional gusts to 25 kt.
Potential for more widespread SCA conditions Tuesday night into
Wednesday with the passage of the cold front. The pressure
gradient then weakens Wednesday afternoon. Ocean seas may
however remain elevated at advisory levels all the way through
the day Wednesday.
Thereafter, mainly sub-SCA conds expected on all waters into late
week.
&&
.HYDROLOGY...
-- Changed Discussion --
The best chance for isolated to scattered flash flooding will
be tonight into early Tuesday morning with a line of showers and
thunderstorms that move into the forecast area from the west.
Rainfall amounts of 1/4 to 1 inch are forecast across the area
with the potential for localized higher amounts, possibly as
much as near 2 inches. Based on upstream observations and radar
estimates, flash flooding could be possible mainly over NE NJ
and immediate adjacent areas. The Weather Prediction Center
continues its slight risk for excessive rainfall through tonight
for much of the forecast area.
Heavy rain is possible late Thursday into Friday, but at this
time there remains too much uncertainty to determine any
potential hydro risk.-- End Changed Discussion --
&&
.TIDES/COASTAL FLOODING...
A high rip current risk for all Atlantic-facing beaches continues
through this evening. A high risk for rip current development
remains high on Tuesday as seas build to around 5 ft with gusty 15
to 20 kt winds.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...High Rip Current Risk until 9 PM EDT this evening for NYZ075-
080-081-178-179.
High Rip Current Risk 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.-- End Changed Discussion --
&&
$$
SYNOPSIS...JP
NEAR TERM...JC/JP
SHORT TERM...JP
LONG TERM...JC
AVIATION...JT/MET
MARINE...JC/JP
HYDROLOGY...JC/JP
TIDES/COASTAL FLOODING...