Islip, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

942
FXUS61 KOKX 301845
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
245 PM EDT Sun Mar 30 2025

.SYNOPSIS...
A stationary front to the south this afternoon will return
north as a warm front and lift through into early Monday
morning. A cold front will approach from the west later Monday
and pass through Monday night, followed by high pressure
building from the northwest on Tuesday. The high will move out
into the Atlantic on Wednesday. A warm front will approach
Wednesday night and move across early Thursday, followed by a
cold front Thursday night. This front will slow down and stall
to the south on Friday, potentially lingering around into the
start of next weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
The front remains well to the south into the Del Marva region.
A cool E flow north of this front will prevail into this
afternoon, with cloudy skies holding. With minimal and weak
lift atop the sfc cold pool and latest trends have removed lower
end PoPs for the time being. Some mist late this afternoon
possible, esp further south and southeast as cloud deck lowers
further. Have lowered max temps for today also by a couple of
degrees in most spots due to getting closer to near sfc saturation
values.

The front begins to return north as a warm front later tonight,
with winds gradually veering SE, and then S late tonight. Fog
should become widespread over a good portion of the area and
especially along the coast, where some dense fog cannot be ruled
out, and some sct showers are possible. Low temps in the 40s
should occur in the evening, then hold steady or slowly rise
overnight. Some spots in NYC and along the coast could get into
the lower 50s before daybreak.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
Cold front approaches Mon into Mon night. Sct showers are
possible in the daytime as heights aloft fall in general, but
the best forcing and heaviest rain will be with the front which
should begin to approach late day and come through at night.
Tstms are also possible, and SPC still maintains a slight svr
risk for wrnmost portions of the CWA. A marginal risk extends E
from there to cover the NYC metro area and SW CT. Instability is
meager and lapse rates poor but wind fields aloft suggest a low
end potential for some damaging wind gusts via downward
momentum transfer. It will be milder with high temps mostly in
the 60s, except reaching the lower 70s in the urban corridor of
NE NJ, and remaining in the 50s along S-facing coastlines mainly
out east. A dry and seasonably cool air mass will follow for
Tue on a gusty NW flow, with highs in the 50s.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Periodic slight undulations in otherwise a mainly zonal flow for
the mid levels. These undulations move across the local area
Wednesday night through Friday. These indicate smaller
wavelength shortwaves within the mid levels that will help
provide vertical synoptic lift.

Airmass mainly dry and colder than normal Tuesday night and
Wednesday. Then, chances for rain showers Wednesday night through
early Friday. A few rain showers are possible late Wednesday
afternoon north and west of NYC, but those POPs are just slight
chance. A low chance of rain/snow mix across parts of the interior
Wednesday night but otherwise a plain rain event. Rain showers could
return for the start of next weekend. Regarding the forecast
temperatures, trending above normal Wednesday night through Thursday
night, then trending back down Friday through Saturday night.

Main chances of rain are Wednesday night through early Friday.
Minimal chances of rain for Friday afternoon through Friday
night when models show the front positioned farther south of the
local region. The longer duration of rainfall Wednesday night
through early Friday does not necessarily mean rainfall for the
entire time. It could very well be periodic or intermittent.

Frontal system will have associated warm front approach
Wednesday night into early Thursday followed by an associated
cold front. The cold front then slows down as the parent low
weakens as it moves into the Canadian Maritimes. The front may
linger nearby the area as a result, maintaining chance of rain
Thursday into early Friday.

Some model forecasts indicate rain showers moving back into the
area for start of next weekend with that same frontal
boundary. This is when model solutions diverge more. Confidence
lower in the forecast but felt enough signal is shown in the
forecast models to warrant having chance POPs for rain.

Regarding temperatures, they start out close to normal for highs
Tuesday and Wednesday and then average above normal for Thursday
and Friday. For the lows, they do not deviate much from normal
Tuesday night and then lows average above normal for Wednesday
night and Thursday night. Only time period with below freezing
temperatures across the interior is late Tuesday night into
Wednesday morning.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
A warm front slowly approaches from the south this evening,
lifting through the area overnight. A cold front approaches on
Monday, passing though at night.

Expect mainly IFR to LIFR conditions through tonight. There is
a chance for some brief improvement to MVFR this afternoon,
mainly in and around the NYC terminals. The better chance for
improvement will come late Monday morning and afternoon in the
warm sector ahead of the cold front, especially for the NYC and
Lower Hudson Valley terminals.

Fog becoming likely tonight as the warm front moves into the
area. Visibilities lowering to IFR and locally LIFR/VLIFR.

East winds 5 to 10 kts will gradually veer overnight, becoming
SSW toward daybreak Monday with wind speeds around 10-12 kt.
Warm front looks to be a bit earlier at some of the eastern
terminals, in particular at KISP, which will be around 06Z.
S-SW gusts 20-25kt develop late Monday morning into early
afternoon. Chance of LLWS at coastal terminals early Monday
with SW winds 40-50 kt at 2kft.

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

Ceilings could fluctuate between MVFR and IFR this afternoon.

Amendments likely for timing of category changes tonight into
Monday.

VLIFR possible tonight.

.OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY...

Monday Afternoon: NYC and Lower Hudson Valley terminals improve
to MVFR, possibly VFR. JFK could remain IFR or lower. Otherwise,
a chance of MVFR or lower in showers, possibly a thunderstorm.
Eastern terminals will likely remain IFR or lower. S-SW wind
gusts 20-25 kt.

Monday night: Showers. Possible thunderstorms. Mainly MVFR for
the NYC terminals, IFR/LIFR at the eastern terminals, possibly
JFK as well. Improving to VFR following cold frontal passage.
SW wind gusts near 20 kt, eventually becoming NW wind gusts
near 20 kt late.

Tuesday: VFR. NW wind gusts 20-25 kt during the day.

Wednesday: MVFR or lower possible at night with a chance of rain
showers. SE wind gusts 15-20 kt.

Thursday: MVFR or lower possible with a chance of rain showers.
SW wind gusts 15-25 kt, highest along the cost.

Friday: VFR.

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

&&

.MARINE...
SCA remains in effect for the central and eastern ocean waters
due to elevated seas still holding in the 5-6 ft range. These
should come down below 5 ft at some point this afternoon.

Areas of fog are likely tonight into Mon morning, and a dense
fog advy may be needed for parts, or all of the waters during
this time frame.

SCA cond likely to return after a warm frontal passage late
tonight into Mon, with S flow gusting to 25-30 kt on the ocean,
ern Sound and the bays of Long Island, and seas building to 5-7
ft. Peak winds Mon evening may hit minimal gale force as a 60-65
kt LLJ passes overhead, but have held off a gale watch as
duration of these stronger winds if they were to occur would be
short, and have mentioned just ocnl 35 kt gusts. SCA cond
likely on all waters late Mon night into Tue in post-frontal NW
flow.

Longer term, SCA conditions for elevated seas probable for much
of the time frame. More widespread SCA gusts seem probable for
most waters on Thursday.

&&

.HYDROLOGY...
Some localized minor flooding, mainly urban and poor drainage, is
possible late Mon and Mon ngt with a frontal sys.

&&

.TIDES/COASTAL FLOODING...
Astronomical levels are high with recent new moon. This combined
with continuous easterly flow has built up water levels. Minor
coastal flooding will be easy to achieve in some areas tonight
around times of high tide.

More sites are forecast to reach minor coastal flood benchmarks
for tonight around times of high tide. This expands beyond the
shorelines of Fairfield CT to also include some other adjacent
shoreline areas along the western Sound as well as the Long
Island South Shore Bays and the Lower NY Harbor. This is where
widespread minor coastal flooding is expected. Most other
shorelines are expected to have isolated minor coastal flooding.

Widespread minor coastal flooding is where advisories have been
issued and the more isolated coastal flooding is where
statements have been issued.

Additional minor coastal flooding is possible around the times
of high tide Monday night.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Coastal Flood Advisory from 11 PM this evening to 3 AM EDT
     Monday for CTZ009.
NY...Coastal Flood Advisory from 11 PM this evening to 3 AM EDT
     Monday for NYZ071.
     Coastal Flood Advisory from 7 PM this evening to 1 AM EDT
     Monday for NYZ074-075-178-179.
NJ...None.
MARINE...None.

&&

$$

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