Oyster Bay, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

925
FXUS61 KOKX 280253
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1053 PM EDT Fri Jun 27 2025

.SYNOPSIS...
High pressure will continue shifting east of the New England
coast tonight as a warm front approaches from the south. The
front lifts through during Saturday morning, followed by a cold
front Saturday night. High pressure returns on Sunday. A frontal
boundary advances back north as a warm front Monday afternoon,
getting captured by low pressure tracking east in Canada. A cold
front follows Tuesday evening with high pressure mid to late
next week.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Made some minor adjustments to the forecast. Added drizzle
wording in addition to making the mention being light through
much of the overnight. Temperatures slightly adjusted to convey
less of a vast range and less spatial variance. Expanded along
the coast the mention of slight chance of thunder per model near
zero Showalter Indices.

The high will begin moving offshore tonight as the upper ridge
starts weakening. This is in response to an approaching shortwave
trough traversing across southeast Canada. The stalled front to our
south across the Middle Atlantic begins lifting north as a warm
front tonight. Clouds will thicken and lower overnight, especially
as the warm front draws closer to the area. Lift with the front is
weak with little to no shortwave energy aloft nearby to add a more
organized area of forcing. Cannot rule out some showers late tonight
and early Saturday morning. Forecast soundings indicate weak lift,
likely from overrunning ahead of the warm front, so some drizzle or
light rain is also possible early Saturday morning. Thunder
chances overnight/early Saturday appear limited with weak
elevated instability nosing in from the southwest late. Have
mentioned a slight chance of thunder from around the NYC metro
on west, but cannot completely rule it out areawide. The
increasing dew points and nearby warm front also support mention
of patchy fog. Turbulent mixing above the boundary layer should
prevent any of the fog from becoming dense. Have mentioned a
slight chance of thunder from around the NYC metro on west.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/...
Main concerns for Saturday will increasing heat indices in the
afternoon as well as potential for an isolated severe thunderstorm
in the late afternoon and early evening.

The warm front will continue lifting north of the area in the
morning. A shower or two remains possible in the morning and
cannot completely rule out a rumble of thunder. Any low clouds,
drizzle and fog diminish by mid to late morning as the flow
becomes southerly and heating takes place. Temperatures will
warm fairly significantly compared to the last few days.
Afternoon highs should reach the low 80s across Long Island and
southern Connecticut due to onshore flow influence. However, the
NYC metro, NE NJ, and Lower Hudson Valley should rise into the
middle and upper 80s. Dew points increase into the lower 70s
yielding max heat indices in urban NE NJ in the mid to upper 90s
with around 90 away from the coast and influence of the marine
layer.

Potential for convection looks to be late in the afternoon and
early evening. Forecast soundings indicate capping around 5 kft
into the afternoon and there may be a weak middle level
cap/warm air to limit convective development. Heights aloft
should fall a bit late in the day with the shortwave moving
across New England. The main forcing will come from surface
convergence and some lift from weak energy aloft. These features
should be enough to allow convection to develop in an
environment with about 1000 J/kg of MLCAPE and about 25 kt of
0-6 km unidirectional shear. The stronger flow/shear looks to
reside northeast of the area and greater instability likely
remains across the Middle Atlantic. CAMs have signaled potential
of a fairly progressive broken line of convection developing
late in the day and moving into the area in the evening. As the
line encounters the marine environment, the line should weaken
as it encounters more stable air across Long Island and
Connecticut towards or just after sunset. SPC has maintained a
marginal risk for a severe thunderstorm west of Long Island and
Connecticut. The main concern is from damaging wind gusts.

Locally heavy downpours are possible as PWATs are increase to
around 1.80 in. However, the progressive nature of the system
will limit duration of heavy rain and limit the overall flood
threat. Minor urban and poor drainage flooding is possible.

The front and shortwave push east of the area Saturday night.
High pressure builds in from the west allowing some drier air to
move into the area. The building high pressure and lingering
troughing just to our east sets the stage for a predominately
westerly flow on Sunday. This should hold off sea breezes until
potentially late in the day. Guidance has trended warmer on
Sunday with highs now in the middle to upper 80s. Heat indices
look to remain near the actual air temperature as dew points
should mix out into the lower 60s due to the westerly flow.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A weakly amplified ridge with high pressure at the surface
keeps conditions mainly dry Sunday night into large portion of
Monday. Mainly clear conditions are expected Sunday night.

Cloud cover may increase late Monday afternoon as the ridge
begins to shift offshore in response to a trough that digs into
the Great Lakes and Canada. This trough also brings surface low
pressure to our north in Canada, which captures a stalled
frontal boundary to our south, bringing it through our area
Monday afternoon as a warm front.

We remain warm-sectored Monday evening into Tuesday evening
before a cold front moves through early Tuesday night. Warm
temperatures, ample moisture, higher dewpoints, and decent
instability should lead to not only showers during this period,
but general thunderstorms. Global models are bringing pockets of
1500-3000 J/kg through the area during this timeframe. Severe
weather looks unlikely until the cold front. Ahead of the FROPA,
bulk shear looks to climb to 35-45 kts which could lead to some
stronger updrafts in longer-lived thunderstorms. This may
support some heavier downpours and instances of damaging winds
in stronger thunderstorms that develop along and ahead of the
cold front.

Late Tuesday night, conditions dry as zonal flow sets in a loft
with high pressure at the surface holding Wednesday into
Friday.

Temperatures Monday and Tuesday range from the mid 80s for most
to lower 90s in parts of the urban NYC metro. With dew pts
progged into the 60s and 70s. Little in the way of temperature
relief behind the front Tuesday night, though drier air in
subsequent W/NW flow helps to lower humidity values mid to late
week.

&&

.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
An approaching warm front tonight into Saturday will give rise
to very light rain or drizzle and overall the development of
lower clouds as well as some fog. Warm front eventually passes
north of the area Saturday, followed by an approaching cold
front towards the end of the TAF period.

Initial VFR conditions through much of this evening are expected to
trend to MVFR to IFR late this evening, overnight and into Saturday
morning. Localized LIFR possible early Saturday. Improvement
back to VFR is forecast Saturday afternoon. Then, chances for
MVFR to IFR return into Saturday evening. For KGON and possibly
KISP, low stratus could return but otherwise for all terminals
there is a chance for showers and thunderstorms which could
bring these temporary MVFR to IFR conditions Saturday late
afternoon into early evening. Have all terminals but KGON with a
mention of thunder towards end of TAF period. Relatively higher
chances of thunder at KSWF so tempo group for that terminal as
opposed to PROB30 for the others.

Regarding winds, it will be an overall easterly flow near 10 kt.
Winds become more ESE later tonight into Saturday and
eventually become more SE-S Saturday late morning through
Saturday afternoon. No significant changes expected in wind
speeds, except within thunderstorms which could bring sudden
shift to more westerly direction and higher gusts.

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

Amendments likely to refine timing of MVFR and IFR. Some
fluctuation between categories possible.

Rain late tonight into early Saturday may end up being just
intermittent drizzle. Amendments likely to refine this timing.

Amendments also likely to refine the timing of thunderstorms
towards the end of the TAF period.


.OUTLOOK FOR 00Z SUNDAY THROUGH WEDNESDAY...

Saturday night: Chance of showers and thunderstorms,
thunderstorms chances lower late evening into overnight.
MVFR to IFR possible.

Sunday: Mainly VFR.

Monday: VFR during the day. A chance of showers and
thunderstorms at night. MVFR or lower possible at night.

Tuesday: Showers and thunderstorms with MVFR or lower possible,
especially afternoon and evening. SW wind gusts 15-20 kt day
into early eve.

Wednesday: Mainly VFR.

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

&&

.MARINE...
Ocean seas have subsided below 5 ft this evening. All marine
zone conditions are expected to remain below SCA thresholds for
the rest of tonight. Winds may increase again on Saturday, but
should remain below 25 kt. Otherwise, conditions will remain
below SCA levels through Sunday.

Sub-SCA conditions are expected Sunday night through early
Tuesday. Winds and waves may approach SCA conditions Tue
afternoon into early Tue night in response to an approaching and
passing cold front. Thereafter, sub-SCA conditions return into
mid & late week.

&&

.HYDROLOGY...
No significant hydrologic concerns are anticipated through next
week. Locally heavy downpours will be quick moving late Saturday
into Saturday evening with only minor nuisance flooding
expected.

&&

.TIDES/COASTAL FLOODING...
Localized minor coastal flooding remains possible for the most
vulnerable spots along the back bays of S Nassau and Queens
during this evening`s high tide cycle, as water levels come down
slightly from a new moon early in the week. No statements were
issued as no impacts are expected.

Surf height lowers to 2 feet Saturday with onshore flow, so rip
current risk will lower to moderate on Saturday. Sunday, winds
shift to westerly for a portion of the day, but rip risk remain
moderate under 2 ft surf height.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$

SYNOPSIS...BR/DS
NEAR TERM...JM/BR/DS
SHORT TERM...DS
LONG TERM...BR
AVIATION...JM
MARINE...BR/DS
HYDROLOGY...BR/DS
TIDES/COASTAL FLOODING...