Area Forecast Discussion
Issued by NWS Upton, NY

Home |  Current Version |  Previous Version |  Graphics & Text |  Print | Product List |  Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
681
FXUS61 KOKX 011738
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
138 PM EDT Tue Jul 1 2025

.SYNOPSIS...
A cold front will approach later today and pivot through late
tonight into Wednesday morning. Another cold front will approach
on Thursday and move through Thursday evening, followed by high
pressure on Independence Day and into the weekend. Another
frontal system may impact the area early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Except for SE CT/eastern Long Island, skies has cleared out as
last night`s convection has pulled off to the east, with
MLCAPE already 1000-1500 J/kg and forecast to increase to
1500-2500 J/kg this afternoon. A pre-frontal trough will set up
from NYC north/west this afternoon as thickness ridging works
into the area (H5-10 values up to 576 dm), a very moisture-
laden air mass with PW 2.2 inches on the KOKX 12Z sounding.

It will be very warm and humid, with high temps in the lower
90s in the urban corridor and heat index values in the
mid/upper 90s in spots within this area. Elsewhere high temps
will be in the upper 80s most elsewhere, and mid 80s along most
south facing shorelines, with heat index values generally
90-95.

There is some question as to when convective initiation will
take place today. Attm most likely scenario appears to be
numerous shower/tstms developing across central/southern NJ by
18Z and drifting up into parts of the NYC metro area and Long
Island, while scattered activity develops to the north/west of
NYC around that same time and exhibits some upscale growth to
multi-cell clusters given effective bulk shear of about 25 kt
as it propagates SE toward the NYC metro area later in the
afternoon and early evening. SPC maintains a slight risk for NJ
and a marginal risk for areas to the northeast, with the main
threat damaging wind from water-loaded downdrafts. Marginal mid
level lapse rates may limit the severe potential somewhat, hence
the slight risk only for NJ.

There could be another pulse of convection later in the
evening/overnight, but it would likely be primarily non-severe
as previous activity may have worked thing over a little and
also getting away from the peak diurnal heating later at night
with the arrival of the actual cold front.

There is also a slight risk of excessive rainfall across much
of the area. Training/repeating storms would be the culprit if
flash flooding were to take place, but at this point leaning
more towards a localized urban related risk due to high
instantaneous rainfall rates.

Kept PoP elevated all night long based on the newest data with
things progressing a tad slower, with higher PoP east into the
overnight. With the cold front more or less slowing late at
night look for a damp and cloudy, muggy night with temperatures
remaining primarily in the 70s, and dewpoints remaining
elevated.

&&

.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
Clouds remain into Wednesday morning as the front struggles to get
further east. Western most location should begin to clear sooner
than eastern sections. Chance showers remain for most of the morning
across eastern most sections, primarily east of the metro. Toward
mid day PoPs really trail off with only a slight chance of lingering
showers across eastern most sections during the afternoon. Dew point
readings will remain elevated and only lower slightly, mainly across
NW sections later in the day. Temperatures overall will be a tad
cooler with mainly middle 80s, with some lower 80s closer to the
coast on a light W to SW wind. More of a sea breeze influence is
anticipated further southeast and along the coast in the afternoon
with a light synoptic gradient and the front more or less washing
out nearby. Cannot totally rule out an isolate shower or storm in
the afternoon as hinted by some CAMs, but have kept this out of the
forecast wording for the time being.

For Wednesday night clouds get further east and mainly offshore late
with only a subtle drop in humidity was dewpoint remain primarily in
the middle 60s across much of the area. Thus temperatures should
only fall into the middle and upper 60s in most places, with lower
70s in the metro, with perhaps a little patchy fog in the outlying
areas possible.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
No significant changes were made to the extended forecast with only
a few minor edits made to NBM guidance.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
A cold front approaches from the west today and stalls over the
area into Wednesday morning.

VFR to start the afternoon. Scattered SHRA, with possible TSRA,
develops into late aft and could lead to MVFR or IFR vsbys at
times. Best window for TSRA generally btwn 19Z and 01Z Wed. SHRA
persist into the overnight, and MVFR cigs likely prevail late
tonight until daybreak or so, then improvement and return to VFR
thru mid morning.

Winds SW 10-15 kt this afternoon with gusts around 20 kt. Flow
becomes lighter tonight, and speeds remain at or under 10 kt on
Wed.

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

Start time of potential shra/tstm this afternoon could be off
an hour or two.

Timing of improvement Wed AM could be off by a few hours.

Isolated shra/tsra possible late Wed afternoon.

.OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...

Wednesday PM: Mainly VFR. Isolated SHRA/TSRA possible late aft.

Thursday: Possible showers and thunderstorms with brief MVFR or
lower possible day into early eve, higher chances north and west of
NYC terminals.

Friday-Sunday: VFR.

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

&&

.MARINE...
As a cold front approaches, S flow will increase, with ocean
seas building to 4-5 ft and perhaps a few gusts close to 25 kt
mainly E of Fire Island Inlet this afternoon into tonight. SCA
remains in effect there but has been cancelled to the west.

Elsewhere, a few gusts close to 25 kt may occur on the eastern
Sound/bays of Long Island later today into this evening.

For Wednesday sub advisory conditions should return on the ocean
with a W-SW wind and ocean seas mainly remaining at around 4
ft. Generally tranquil conditions Wednesday night through
Saturday will result in sub-SCA on all waters.

&&

.HYDROLOGY...
There is a slight risk of rainfall for most of the area through
tonight. With high PW in place instantaneous rain rates should
be high, with to a localized risk of flash flooding in stronger
thunderstorms. Repeating/training cells could lead to a higher
risk, which is possible given deep layer SW flow with speeds
getting over 30 kt in the mid levels.

&&

.TIDES/COASTAL FLOODING...
There is a high risk of rip currents today, and this could also
be the case into Wednesday, with wave heights not coming down
much, along with a lingering 9-second E swell component.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents until 9 PM EDT this evening for NYZ075-
     080-081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EDT Wednesday for ANZ350-353.

&&

$$

SYNOPSIS...JE
NEAR TERM...JE/BG
SHORT TERM...JE
LONG TERM...
AVIATION...JC/DR
MARINE...JE/BG
HYDROLOGY...JE/BG
TIDES/COASTAL FLOODING...