000
FXUS61 KOKX 251146
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
746 AM EDT Sun Jun 25 2023

.SYNOPSIS...
A weak trough remains near the region through tonight. Another
trough of low pressure approaches from the west on Monday,
followed by a slow moving frontal system through late in the
week. Weak high pressure may try to move in Friday ahead of
potentially another frontal system.

&&

.NEAR TERM /THROUGH TONIGHT/...
Main concern early this morning continues to be with dense fog.
Visibilities continue to be around 1/4 mile or less across
Nassau and Suffolk counties as well as along coastal CT along
the I-95 corridor. A dense fog advisory remains in effect until
9 am. Have also issued an SPS for locally dense fog across
interior CT and Westchester and Putnam counties. Visibilities
should begin to improve after 9 am.

Otherwise, dry conditions will start the day before convection
begins to develop in the afternoon. The remnant upper low
continues to spin towards the region today and will interact
with a lingering surface trough. Convergence from sea breezes
may also help focus convective development. Think the greatest
coverage will lie near and just west of the NYC metro into
northeast New Jersey and the Lower Hudson Valley, similar to
what occurred on Saturday. While a shower or isolated storm
cannot be ruled out from east, coverage should end up isolated.
Any shower/storm will be capable of producing minor flooding in
low lying or poor drainage. A localized flash flooding
occurrence cannot be ruled out and WPC has continued to indicate
a marginal risk for excessive rainfall mainly just north and
west of the NYC metro. Highs today should be able to warm into
the 80s, warmest in the NYC metro.

Daytime convection likely weakens during the evening with loss
of heating. However, guidance has trended towards keeping the
middle level vort energy strong enough to produce a shortwave
reflection. Another larger upper low will be moving across the
Great Lakes tonight, which should help lift the energy over the
region tonight. Showers and possibly a thunderstorm remain
possible tonight and have kept PoPs at chance to account for
this potential. Low clouds and fog are also possible, especially
along and near the coast, similar to what has been observed
this morning. Not confident yet if the fog will become dense due
to the potential shower activity and increase in middle level
clouds. It will remain muggy with lows in the mid to upper 60s.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
Monday could be a more active day with potential of strong to
severe thunderstorms and localized flash flooding.

The larger upper low and associated trough will continue to
move towards the Middle Atlantic and northeast through the day.
The main frontal system and low pressure will still lie well
west of the region, but a pre-frontal trough likely sets up
nearby in the afternoon and evening. This trough will be a focus
for a potential line of showers and thunderstorms. The
atmosphere is progged to become more unstable and bulk shear
values look to increase to around 30-35 kt. These ingredients
support potential for some of the thunderstorms to become strong
to severe. Model soundings indicate around 1000 J/kg of surface
based CAPE. One potential negating factor is a potential
inversion or cap in the lower levels. This is due to the winds
close to the surface coming out of the S to SE. The maritime
influence could act to suppress the intensity of the
convection. However, SPC has placed portions of the Lower Hudson
Valley, NYC metro, NE NJ, and western LI in a slight risk and
the rest of the area in a marginal risk. The guidance does have
a signal for a potential line of storms to move through in the
late afternoon and evening. More of the CAMs will be in range
over the next 12 hours, so we should start to gain more
confidence in how the environment and convection will evolve.

The severe potential diminishes Monday night, but showers and
thunderstorms remain possible. The upper trough will be in
place over the eastern states and areas of energy may lift
northward ahead of the closed low near the Great Lakes. These
unsettled conditions will continue into Tuesday. Probabilities
for precipitation look high based on model consensus. However,
it is a bit difficult to determine what specific time period
Monday night into Tuesday would favor more widespread showers
and thunderstorms. Strong to severe thunderstorm risk on Tuesday
is a bit lower, but still marginal for part of the area based on
SPC Day 3 outlook.

Minor poor drainage and low lying flooding is possible in any
convection Monday through Tuesday. There is also a localized
risk of flash flooding, especially in any areas where training
of heavy downpours occurs. WPC maintains a marginal risk of
excessive rainfall on Monday and Tuesday.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
The unsettled pattern will continue through the long term, with
the only chance of a brief reprieve and perhaps more intervals
of sunshine overall towards Fri / Sat. Coverage of showers and
storms may start lessen on Wednesday as the deeper moisture axis
starts shifting to the east. However, the upper trough and
closed low will only slowly move overhead into Thursday. Shower
and scattered t- storm activity remains possible, especially in
the afternoon and evening. The trough and associated frontal
system may start to shift to the east on Friday, but confidence
how this evolves is still quite low.

Look for daily max temps to average below normal with a good deal
of daytime cloud cover anticipated on average throughout the
period. There may be a day towards Fri or Sat where daytime
temps may get closer to normal. Night minimums should average
close to normal with higher humidity and a good chance of night
time cloud cover.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
A weak low pressure trough will remain nearby.

LIFR cond mainly along/closer to the coast at
KISP/KHPN/KBDR/KGON and also inland at KSWF should last until
13Z-14Z, perhaps longer at KGON.

There is a chance of showers later this morning, becoming
likely this afternoon. Tstms also possible from the NYC
terminals north/west mid-late afternoon into early evening. Best
chances will be at KSWF/KEWR/KTEB and included in a TEMPO.
Can`t totally rule out thunder at KLGA/KJFK/KHPN, with TEMPO
only for showers attm.

A repeat of fog and low stratus with IFR/LIFR cond appears
likely for tonight. Timing highly uncertain but more likely
after midnight.

S winds 5-10 kt expected this afternoon, diminishing this
evening and then backing SE overnight.

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

Slight chance of a tstm at KJFK/KLGA late this afternoon,
probability still too low for TAF mention attm. Timing of return
of lower cond tonight uncertain.

The afternoon haze potential forecast for KJFK is YELLOW, which
implies slant range visibility 4-6SM outside of cloud.

OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...

Monday: Showers. Chance of tstms with gusty winds and from the
NYC metros north/west, especially afternoon/evening. MVFR cond
expected, IFR possible.

Tuesday and Wednesday: Showers. Tstms with gusty winds and hail
possible, especially afternoon/evening. MVFR cond expected, IFR
possible. Tuesday S winds G20-25kt.

Thursday: Chance of showers and a slight chance of tstms. MVFR
or lower possible at times.

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

&&

.MARINE...
Dense fog advisory remains in effect until 9 am for all but the
NY harbor and ocean west of Fire Island Inlet. Have replaced
the advisory for the ocean west of Fire Island Inlet with a
marine weather statement as the fog is present and dense along
the shoreline. The advisory may need to be expanded for some of
the zones a few hours longer if the fog is slower to improve.

Otherwise, both winds and seas are expected to remain below SCA
levels through tonight night. Conditions should stay below SCA
levels on Monday, but increasing towards SCA levels Monday night
and especially on Tuesday in a fairly strong S flow. Winds may
end up closest to 25 kt on the ocean Tuesday with seas 5-6 ft
Monday night through at least Wednesday night. Elevated seas may
persist into Thursday.

There is potential for fog tonight, similar to what has been
observed early this morning. The fog could become dense across
some of the waters as well.

&&

.HYDROLOGY...
Locally heavy rainfall is possible this afternoon and evening in
any shower or thunderstorm. Minor poor drainage and low lying
flooding is the main concern although a localized flash
flooding occurrence is possible across NE NJ or the Lower Hudson
Valley if training of slow moving storms were to occur.

There is a continued risk of minor flooding and localized flash
flooding mainly late Monday into Tuesday in showers and
thunderstorms. The threat is largely for the entire area and
WPC has maintained a marginal risk for excessive rainfall
through Tuesday.

Hydrologic impacts are possible Wednesday into Thursday, but may
end up related to where the heaviest rainfall occurs today
through Tuesday. WPC currently has a marginal risk of excessive
rainfall NW of the NYC metro.

&&

.TIDES/COASTAL FLOODING...
The moderate risk of rip current development continues for all ocean
beaches through Monday mainly due to southeasterly swells.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Dense Fog Advisory until 9 AM EDT this morning for CTZ009>012.
NY...Dense Fog Advisory until 9 AM EDT this morning for NYZ078>081-
     177-179.
NJ...None.
MARINE...Dense Fog Advisory until 9 AM EDT this morning for ANZ331-332-
     335-340-345-350-353.

&&

$$
SYNOPSIS...JE/DS
NEAR TERM...DS
SHORT TERM...DS
LONG TERM...JE/DS
AVIATION...BG
MARINE...JE/DS
HYDROLOGY...JE/DS
TIDES/COASTAL FLOODING...