Southampton, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

563
FXUS61 KOKX 120603
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
203 AM EDT Thu Jun 12 2025

.SYNOPSIS...
Weak high pressure remains nearby overnight. A cold front
approaches on Thursday and swings through Thursday night. The
front then stalls nearby or just to the south during Friday into
Saturday and will slowly work south into the Mid Atlantic into
early next week. Waves of low pressure will track along the
boundary during this time. The front will then return northward
as a warm front toward the middle of next week.

&&

.NEAR TERM /THROUGH TODAY/...
Weak high pressure remains nearby overnight, to the south and
southwest. This should provide primarily clear skies. With a
weak pressure gradient expect light winds mainly out of the SW.
Temperatures should be close to normal, perhaps a couple of
degrees above normal. With the lack of an onshore wind component
overall, there should be enough of a temperature and dew point
separation to preclude fog development, although locally a
little patchy fog cannot be completely ruled with night time
minimums mainly in the 60s.

Weak high pressure then drifts further east to our south on
Thursday, with a cold front approaching from the west-northwest
in the afternoon. It will be a moderately humid day with
dewpoints primarily in the lower 60s with the region just south
of the polar jet. BUFKIT forecast soundings are suggestive of at
least a conditional convective chance, especially for the
western half of the area later in the day and early evening.
Moderate CAPE profiles are evident with over 1000 J/kg of CAPE
for many sites, with lower CAPE further east. Would have to get
parcel to 5 kft to enable lifting above the LFC. Exact timing
and placement of the approach of the cold frontal boundary will
dictate where and exactly when convection will try to initiate.
The conditionality with respect to convective chances comes from
signs of warmer air in the mid levels and some potential
capping. If the capping is weaker or non-existant than a few
strong to severe storms would be possible with the jet just to
the north and 40 kt bulk shear in place. Thus, if convective
initiation is achieved, then the potential for storm
organization and maintenance would be high. For now will hold
off on any enhanced wording due to the high conditionality of
any convection and carry slight chance and isolated wording for
the late afternoon and evening. Look for a noticeably warmer day
overall with daytime maximums primarily in the 80s region wide,
with some spots in urban NE NJ getting to 90.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM FRIDAY/...
For Thursday night the cold front is progged to push through as
the shortwave feature gets further east and in its wake later
at night surface high pressure attempts to ridge down from the
northwest out of Canada. Carry slight chance PoPs early on with
showers and isolated thunder chances, with skies later on going
partly cloudy to mostly clear on a light NW to N flow. With the
light wind behind the boundary if any convection did occur some
localized patchy fog would be possible late where any rain or
convection occurred, but due to the high conditionality of any
previous shower or convective activity have chosen to keep any
patchy fog wording out of the forecast for the time being.
Dewpoint readings should drop some by early Friday morning into
the middle and upper 50s, thus some drop in humidity levels is
expected.

A sunny start is expected during Friday with weak sfc ridging
working in during the morning. However, the cold front which
moved through Thursday night is not progged to get very far to
the south and is expected to stall nearby, perhaps just to the
immediate south. This scenario would likely set up an light
onshore flow, especially during the afternoon along and north of
the boundary. Any light onshore flow would keep temperatures
somewhat cooler from the previous day. There is a chance that
the flow will be quite weak and won`t really penetrate much
inland. Thus temperatures should be able to reach the 80s,
perhaps middle 80s inland during the day Friday. Coastal
sections are likely to be in the upper half of the 70s to around
80, thus closer to normal. A mid-level shortwave is forecast to
approach later in the day and evening. This could trigger some
shower activity late in the day and evening. Thus have re-
introduced slight chance PoPs across far western sections late
in the day.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
The forecast area during this time will reside on the southern
edge of the westerlies which is likely to keep the area
unsettled into early next week. A frontal boundary just south of
the area on Saturday will settle slowly south into the Mid
Atlantic states into early next week before returning northward
mid week. The challenging part of the forecast is
timing/location of frontal waves along the boundary and the
associated rainfall. Airmass is marginally unstable over the
weekend along with PWAT values approaching 2 inches. Thus, there
could be some downpours, but by no means will it be raining all
the time. Forecast running with chance PoPs (30-50%) over the
weekend into early next week with a chance of showers and
embedded thunderstorms. Shortwave energy passing to the north on
Sunday will be followed by high pressure building across
eastern Canada and into the Northeast. This looks to push the
front farther south into Monday with even some drying of the
airmass. Airmass should be stable enough to limit convection to
mainly showers at this time. 12Z global models are in good
agreement taking low pressure off the Mid Atlantic coast early
Tuesday, passing to the south and east. Forecast area will be on
the northern periphery of the system and may be far enough
removed from the stratiform rain shield. Rain chances will be
lower during this time.

Temperatures Saturday through Monday will trend down through
the 70s and in some cases may struggle to get above 70 with an
easterly flow and cloud cover. Temperatures will then begin to
climb back up to normal by Tuesday and even above by Wednesday
as heights begin to rise and the front starts returning
northward as a warm front. Lows will be close to normal, but
night will be humid with dew points around 60. NBM box and
whisker temperatures plot shows large difference between the
25th and 75th percentiles from Saturday into Tuesday, likely due
timing of the frontal waves and rain.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
Weak high pressure builds over the terminals through the
overnight. A weak cold front slowly approaches from the
northwest on Thursday, moving into the Lower Hudson Valley late
in the afternoon and through the remaining terminals during the
evening. An isolated shower or thunderstorm is possible late
Thursday afternoon into the early evening. More of the higher
resolution models are keying in on a line of showers and
isolated thunderstorms moving through, so have added VCSH from
around 00Z to around 06Z (+/- an hour or so, depending on
terminal location, with eastern terminals occurring earlier).
At this time however, there is a fair amount of uncertainty with
exactly where and when these showers and isolated thunderstorms
will occur. The chance for thunder significantly lowers after
03Z Thursday.

Generally VFR through the TAF period. Brief MVFR or lower in any
showers or isolated thunderstorms that might move through
Thursday evening.

A SW/WSW flow continues through the overnight, with a few
locations becoming light and variable. A W flow develops
Thursday morning and increases into the early afternoon,
becoming 10-15 kt with gusts up to 20 kt possible. The flow may
start shifting to the SW near the coast early afternoon, with a
sea breeze possible at KJFK by late afternoon. Sea breezes are
also possible at KISP, KBDR, and KGON, though these may not be
true sea breezes with a slight westerly component to the true
sea breeze.


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

Isolated shower/thunderstorm possible Thursday afternoon and early
evening.

Timing of afternoon sea breeze Thursday at KJFK may be off by
1-3 hours, and possible that the sea breeze does not move into
KJFK.


.OUTLOOK FOR 06Z FRIDAY THROUGH MONDAY...

Thursday Night: VFR. There`s a low chance (due to uncertainty in
timing) that showers move through between 06Z-12Z, which may
bring brief MVFR or lower conditions.

Friday: Mainly VFR.

Friday Night-Saturday: MVFR or lower possible with a chance of
showers and a few thunderstorms possible.

Sunday: MVFR or lower possible. Chance of showers with isolated
thunderstorms possible.

Monday: MVFR or lower possible. Chance of showers.

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

&&

.MARINE...
Sub advisory conditions are anticipated in the near and short term
for all waters. Across far eastern portions of the ocean there will
be 4 ft and just under 5 ft seas at times for a portion of tonight.
Otherwise seas gradually decline to 2 to 3 ft by Thursday afternoon,
and closer to 2 ft into Friday.

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 from
Saturday through Monday.

&&

.HYDROLOGY...
There are no hydrologic concerns through the short term, other than
the low chance of some nuisance urbanized minor flooding in
association with an isolated thunderstorm late Thursday. Showers and
embedded thunderstorms may produce localized heavy rainfall on
Saturday. WPC has portions of the area under a marginal risk of
excessive flooding. This represents a low probability of flash
flooding.

&&

.TIDES/COASTAL FLOODING...
A gradually diminishing southerly swell will result in another
day of a moderate rip current risk Thursday, but lowering to a
low risk on Friday.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Air Quality Alert until midnight EDT tonight for NYZ067>075-
     078>081-176>179.
NJ...Air Quality Alert from 11 AM this morning to 11 PM EDT this
     evening for NJZ004-006-103>108.
MARINE...None.

&&

$$

SYNOPSIS...JE/DW
NEAR TERM...JE
SHORT TERM...JE
LONG TERM...DW
AVIATION...JP
MARINE...JE/DW
HYDROLOGY...JE/DW
TIDES/COASTAL FLOODING...