484
FXUS61 KOKX 091931 CCA
AFDOKX

Area Forecast Discussion...CORRECTED
National Weather Service New York NY
331 PM EDT Mon Jun 9 2025

.SYNOPSIS...
A wave of low pressure will lift a frontal boundary north through
the area tonight into Tuesday morning, with a cold front following
Tuesday evening. High pressure then builds in on Wednesday and
remains near the region through Thursday. Meanwhile low pressure
passing well to the north will send a cold front through the
region late Thursday night into early Friday. The front then
becomes nearly stationary into the beginning of next week, with a
series of lows moving along the stalled front.

&&

.NEAR TERM /THROUGH TUESDAY/...
Heights gradually fall aloft today as a broad upper level trough
approaches. At the surface, a wave of low pressure is approaching
from the south along a frontal boundary. This boundary will move
north through the area tonight into Tuesday morning.

Shower activity is ongoing mainly in the Lower Hudson Valley. This
activity should continue to decrease through the afternoon and
evening as an embedded shortwave moves east of the area. However,
given the easterly flow and weak overall lift, some drizzle and
or sprinkle activity could continue through the night. Also, in
combination with the onshore component of the flow, the
pressure gradient weakens quite a bit tonight. This gives
increased confidence in fog, especially because some is being
observed along the coast already. Difficult to say at this time
exactly how low the visibility will get, but dense fog is
definitely not out of the question.

The main show in the near term will be heavy downpours Tuesday
morning into the early afternoon. The aforementioned broad
upper level trough continues approaching and more embedded
shortwaves will move into the area. By this time, the frontal
boundary will be north of the area and pwats across the southern
half of the area will surge to 1.75 to 1.90 inches. According
to SPC Sounding Climatology, this is well above the 90th
percentile for June 10th and right around the daily max that has
been observed. Along with this available moisture, there is
also deep lift with continued falling height and an upper level
jet streak placing us right under the right rear quadrant. All
of this will lead to widespread moderate showers with embedded
heavy downpours. Timing for this is mainly 5am to 1pm for NYC
north and west and then 7am to 4pm for locations north and east
of NYC. At this time there is just an isolated threat for flash
flooding, with the main threat being minor poor drainage
flooding. See Hydrology section below. Have lowered thunder
chances down to slight chance with the morning activity. All
instability appears to be elevated and weak and really only
expecting some isolated rumbles of thunder. Additionally, the
bulk of the CAPE profile looks to be below -10C.

The rest of the day then looks mostly dry, with maybe some
lingering isolated lighter showers. There will however likely
be isolated showers/thunderstorms when the cold front moves
through in the evening. This will depend on how well we can
clear out and how unstable we can get in the afternoon ahead of
the front. The CAMs are hinting at clearing out enough and even
reaching 500-1000 J/kg of MLCAPE in the Lower Hudson Valley.
This aligns with the model reflectivity fields showing a few
cells pop up along the cold front, also mainly in the Lower
Hudson Valley. This activity should be really isolated and the
lack of moisture will likely work against development. Pwats
drop pretty quick in the afternoon once the morning showers move
east. By 00z pwats likely drop down to 1 inch or lower. At this
time severe weather is not expected, but given decent shear it
can not be completely ruled out yet.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/...
High pressure gradually builds in thereafter leading to dry
conditions and a warming trend. The flow aloft becomes zonal
with some slight height rises. Stuck close to the NBM for this
period, with just a slight upward adjustment with temperatures
for the interior on Wednesday. Also lowered Td a bit given the
NBM high bias for drier regimes.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
The long term forecast period will be dominated by a mid and upper
level trough, mainly across eastern Canada, and into Northern New
England, with nearly zonal flow across the Midwest, and into the
Northeast, and Mid Atlantic region. Global guidance is fairly
similar through the extended period. A cold front is forecast to
move through the region late Thursday night into early Friday
morning, and then become nearly stationary to the south of the area,
through the Mid Atlantic region and the Delmarva, into early next
week. There is some uncertainty as to how far south the frontal
boundary will setup. The will affect the track of waves of low
pressure that are forecast to track along the boundary. And some
guidance that the front may drift farther south late in the weekend
into early next week. Also, the placement of the boundary will
affect temperatures, mainly Saturday through Monday, with more
uncertainty in highs and low seen in the spread of possibilities with
the NBM guidance. As a result of the uncertainty, and no targets of
opportunity, have stayed close to the NBM deterministic
guidance.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
Predominantly LIFR-IFR conditions are expected to persist
overnight in response to a warm frontal boundary very slowly
moving through the area. Persistent light onshore flow will
also contribute to the development of fog overnight, possibly
dense with visibilities 1/2 SM or less.

Showers and thunderstorms are then expected to develop right
around the morning push moving from west to east, with the
heaviest activity between about 14-18Z. Rainfall may be heavy at
times maintaining reduced visibilities across the airspace. As
the activity diminishes into the afternoon, ceilings and
visibilities will gradually improve to MVFR-VFR. A cold front
then approaches later in the evening, but convective activity is
not expected to be as widespread.

Winds will primarily be light from the east to east-southeast
until the front approaches from the west Tuesday evening,
allowing winds to veer to the west-southwest. Occasional gusts
may be possible through 20-21Z this evening for LGA, ISP, BDR,
and GON.

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

Amendments possible throughout the entire TAF period for changing
flight categories especially with ongoing shower and drizzle activity.


.OUTLOOK FOR 18Z WEDNESDAY THROUGH SATURDAY...

Wednesday - Thursday: VFR with gusty W flow.

Friday - Saturday: VFR except in scattered showers and
thunderstorms.


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

&&

.MARINE...
A Dense Fog Advisory has been issued for all waters as
confidence in 1 mile or less visibilities has increased. For
now, the hazard is in effect until 6AM Tuesday morning, but it
may need to be extended.

Winds and waves likely remain below Small Craft Advisory criteria
through Wednesday. There is a brief period late Tuesday night into
Wednesday morning where the eastern ocean waters could see 5 ft
seas.

With a weak pressure gradient force expected across the forecast
waters, as a frontal boundary remains in the vicinity of the ocean
waters, winds and seas are expected to remain below SCA levels.

&&

.HYDROLOGY...
Showers and thunderstorms Tuesday morning through the early
afternoon will bring moderate to locally heavy downpours to the
area. While average total rainfall is expected to be between
0.50 and 1.00 inches, any isolated stronger shower or
thunderstorm has the potential to put down 0.75 to 1 inch in an
hour. The WPC continues to highlight the area in a marginal risk
and the biggest threat is minor urban and poor drainage
flooding, with an isolated threat for flash flooding.

No hydrologic impacts are expected Tuesday night through next
Monday.

&&

.TIDES/COASTAL FLOODING...
A moderate risk of rip current development remains through this
evening.

For the ocean beaches the moderate risk for the development of
rip currents remains for Tuesday. However, with increasing south
to southwest winds and building surf across the southeastern
Suffolk ocean beaches the risk may be increased to high.

For Wednesday: the moderate rip current development risk
remains for the ocean beaches of New York City, and Nassau
county. There is a chance that the threat increases to high for
the Nassau ocean beaches with increasing southerly flow. And
for the Suffolk county ocean beaches the rip current risk is
forecast to be high.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Dense Fog Advisory until 6 AM EDT Tuesday for ANZ331-332-335-
     338-340-345-350-353-355.

&&

$$

SYNOPSIS...MET/JT
NEAR TERM...JT
SHORT TERM...JT
LONG TERM...MET
AVIATION...MD
MARINE...MET/JT
HYDROLOGY...MET/JT
TIDES/COASTAL FLOODING...MET