000
FXUS61 KOKX 012043
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
443 PM EDT Tue Aug 1 2023
.SYNOPSIS...
High pressure builds across the area through Wednesday and then
offshore by Wednesday evening. A frontal system approaches from
the west on Thursday. A warm front pushes through late Thursday
night into Friday morning, followed by a cold front Friday
night. High pressure returns for the weekend. A frontal system
then approaches and may push through Monday and Monday night,
possibly followed by another cold front on Tuesday.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
A full latitude trough along the east coast will gradually work
offshore through Wednesday, with slowly building heights.
At the surface, high pressure centered over the eastern Great
Lakes this evening builds toward the area. This will keep the
area under a dry, unseasonably cool airmass with lows by morning
6 to 10 degrees below normal. Lows will range from the upper
40s/lower 50s well north and west of the NYC metro, to the upper
50s/lower 60s along the coast. The Pine Barrens region of LI
may bottom out right around 50. The one limiting factor will be
a northerly flow of 5 to 10 mph which will keep the airmass a
bit more mixed.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
High pressure builds across the area through early afternoon
Wednesday, then offshore by evening. A weak return southerly
flow will set up in the afternoon. The airmass will still be dry
and just below normal with highs in the upper 70s to lower 80s.
For Wednesday night into Thursday, high pressure builds out into
the western Atlantic with a frontal system moving across the
Great Lakes. Aloft, a shortwave trough drops across the Great
Lakes. This will result in a ramping up southerly flow on
Thursday with increasing humidity and slightly warmer
temperatures. Clouds will be on the increase Thursday with a
chance of late day showers, mainly north and west of NYC.
Airmass initially stable enough to rule out thunderstorms at
this time.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A warm front approaches to begin the period on Thursday night. A
southerly flow gets going in earnest early in the period. The warm
front should push through, or at least begin to push through Friday
morning. Have introduced shower chances Thursday night, with rain
chances increasing during the day Friday with some likely PoPs
included. As the warm front pushes through look for thunder chances
to increase with a cold front still upstream and higher instability
pushes into the area during the day Friday. With the cold front
right behind the warm front there are questions as to how much sun
can break through before the arrival of the cold front. If enough
surface based instability can get involved then the ante would be
upped for severe weather later Fri and Fri evening. For now have
just included a general thunder chance.
The cold front swings through later Fri night bringing any precip
and possible convection to an end. The winds switch to a drier NW
direction. This will set the stage for lower humidity and dry
conditions into the weekend as the latest global guidance continues
to lean on a more progressive upper trough solution late Fri into
early Sat. Thus the weekend looks like a good weather weekend with
seasonable temperatures and tolerable humidity.
Another system approaches on Monday. There remains some uncertainty
with the deterministic global guidance. A consensus approach was
taken and by and large used an NBM / Superblend mix for late in the
period, especially with regards to PoPs into Monday. There is the
potential for thunderstorms and possible severe weather if certain
ingredients come together later Monday. Temperatures through the
period will be for the most part right around normal.
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
VFR as high pressure builds over the terminals through tonight
and remains on Wed.
Southerly sea breeze came in at KJFK at 20Z and may make a run
at KLGA from 22Z-24Z. Can`t rule out a nearby isolated shower
during that time that could play havoc with the wind forecast
at both terminals. Sea breeze also coming in south of KISP,
think it may get into the vicinity airspace to the south but not
impact the terminal itself.
Otherwise, light N flow continues into this evening, varying at
times from NNW to NNE. Ocnl G15-18kt possible at KEWR til about
23Z. Winds will stay northerly this evening, weaken into the
overnight, becoming light and variable at outlying terminals,
then resume Wed morning.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Sea breeze may make it to KLGA between 22Z-24Z. Any isolated
showers that develop near KLGA/KJFK around that time may play
havoc with wind fcst. Gusts at KEWR may be more brief/ocnl
rather than frequent.
Sea breezes are likely Wed afternoon after about 17Z.
OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
Wednesday afternoon and night: VFR.
Thursday: Mainly VFR. Slight chance of afternoon showers
mainly NW of the NYC metros.
Thursday night: Chance of showers and possibly a tstm, with
MVFR cond possible.
Friday: Showers/tstms likely. MVFR cond likely, IFR possible.
Saturday: Chance of MVFR cond in showers/tstms early in the
morning E of the NYC metros, otherwise VFR.
Sunday: VFR.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
High pressure over the eastern Great Lakes will build toward the
area tonight and then across the waters on Wednesday. The high
then gives way to a frontal system over the Great Lakes late
Wednesday night into Thursday. This will result in a gradually
increasing southerly flow on Thursday, but with winds and seas
remaining below SCA criteria.
By Thursday night gusts on the ocean start to get to 20 kt, with
ocean seas closer to 4 ft. By midday Friday small craft conditions
will be likely on the ocean as gusts approach 25 kt and seas get to
5 ft., with small craft conditions also possible on a good portion
of the non-ocean / nearshore waters. A cold front is progged to
swing through Friday night resulting in a wind shift to the NW. Seas
will come down late Friday night into early Sat AM. The pressure
gradient relaxes Saturday with building high pressure and a lighter
wind resulting in 3 to 4 seas on the ocean.
&&
.HYDROLOGY...
No hydrologic concerns exist at this time through the weekend.
There is some potential for heavy rain in association with any
thunderstorms early next week towards Monday, but there remains
a lot of uncertainty this far out in time.
&&
.TIDES/COASTAL FLOODING...
There is a low risk of rip currents today. There is a moderate risk
of rip currents on Wednesday with 1 ft 11-12s southeasterly
swells. The moderate rip risk Wednesday may come very late in
the day.
Astronomical tides continue to increase with the full moon
tonight. Based on several sites achieving minor flooding last
evening and surge values of 0.5 to 0.8ft, have opted to issue an
advisory for the south shore back bays of Queens and Nassau for
tonight. Expecting minor flood benchmarks to be exceeded by only
0.3 or 0.4ft or so during high tide. A statement was issued for
southern Fairfield county, with minor benchmarks expected to
just be reached.
Additional minor flooding is possible during Wednesday evenings
high tide cycles, and statements and/or advisories may be
needed.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...Coastal Flood Advisory until 9 PM EDT this evening for NYZ178-
179.
NJ...None.
MARINE...None.-- End Changed Discussion --
&&
$$
SYNOPSIS...JE/DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...JE
AVIATION...BG/MET
MARINE...JE/DW
HYDROLOGY...JE/DW
TIDES/COASTAL FLOODING...