Islip, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

387
FXUS61 KOKX 051602
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1202 PM EDT Sun Apr 5 2026

.WHAT HAS CHANGED...
Marine Dense Fog for all coastal waters except the NYC Harbor
have been extended until 2 pm.

Slightly cooler high temperatures are expected today with
abundant cloud cover and rain moving in in association with a
approaching cold front. Highs will be in the 50s across Long
Island and southern CT, while NYC metro, NE NJ, and the Lower
Hudson Valley will see upper 50s to middle 60s.

&&

.KEY MESSAGES...
1. A cold front moves through today bringing a period of
rainfall perhaps with some thunder. Dry conditions then follow
for much of the week.

2. Temperatures warm to near seasonable levels Thursday,
followed by an increasing probability of above normal
temperatures for later in the week.

&&

.DISCUSSION...
.KEY MESSAGE 1...
A cold front approaches from the west this afternoon and will
push east through the day, bringing with it a period of light to
moderate rainfall, perhaps with some embedded thunder given
some marginal elevated instability. Overall, 0.25-0.5" of
rainfall is expected, perhaps a bit higher in any locations with
heavier embedded convection or a thunderstorm.

After the front moves through, much of the rest of the week
looks to be mainly dry as a large Canadian high pressure system
builds into the area mid-week. A weak disturbance may however
bring some showers for inland areas Monday night into Tuesday,
but PoPs are only 30 percent at this time.

.KEY MESSAGE 2...
Behind the cold frontal passage today, temperatures will remain
generally below average through the middle of the week,
generally reaching their coldest on Wednesday with highs only in
the middle to upper 40s.

THe high moves offshore Wednesday night into Thursday allowing
for a more moderate airmass to advect into the area toward the
end of the week. Temperature uncertainty increases Thursday,
mainly due to uncertainty around the sfc wind direction. With
water temperatures still quite cold a more southerly or easterly
component to the wind as opposed to a more westerly component
will have a big effect on temperatures. Also, 5 kft temperatures
really don`t warm significantly until Friday into Saturday.
Thus, have stayed with the NBM temperature guidance through
Thursday night. However, with a cold front that likely washes
out with rising heights just upstream look for the potential for
noticeably warmer temperatures than consensus guidance is
currently indicating for Friday, and on Saturday as well. For
now staying close to the NBM, but there is a higher than average
chance for adjustments going forward in time.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
A warm front is struggling to lift through portions of the
terminal forecast area, but has lifted across Long Island. It`s
quite possible that the cool sector with the low clouds and fog
across the NYC metro and Lower Hudson Valley terminals doesn`t
get eroded until the cold frontal passage early this afternoon.
LI likely stays IFR due to high dew point air in the warm sector
moving across the much cooler waters.

Mainly IFR or lower today with FG and DZ, this mrng, then rain
with the cold front in aftn. Becoming VFR aft the fropa late
this aftn, then remaining VFR thru the rest of the TAF period.

Winds expected to shift to the S/SW, then W/WNW by late day
behind the fropa. Wind shift to the SW may not happen across
some of the Lower Hudson Valley and NYC terminals until cold
frontal passage. Gusts around 20-25 kt develop this aftn and
persist thru Mon.

 ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Challenging forecast this morning into this afternoon with a
warm front struggling to lift through the NYC metro. In fact,
there is a chance this does not happen until cold frontal
passage around 18Z.

Amendments very likely for changing conditions thru about 21Z,
then VFR.

.OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...

Monday: VFR. W-NW winds with gusts around 25kt.

Tuesday: Mainly VFR. Low chance MVFR or lower possible in any
showers. W winds around 10 kt with G15-20 kt.

Wednesday: VFR. N winds becoming NE at 10 kt or less.

Thursday: VFR.

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

&&

.MARINE...
With fog still affecting much of the coastal waters, except the
harbor, the Marine Dense Fog Advisory was extended until 2 pm.
Thereafter, increased wind along with rain approaching from the
west should help to scour out the fog. Visibilities to 1 NM or
less are expected.

A Small Craft Advisory is in effect for the ocean along with
much of the non-ocean waters through this afternoon, with the
exception of NY Harbor and the W LIS.

Waves on the ocean will remain above 5 ft and southwest winds
will then ramp up later this morning ahead of an approaching
cold front. Gusts up to 30 kt will be possible on the waters
where a SCA is in effect. A strong inversion over the waters is
expected to keep gusts below gale force, though an occasional
gale-force gusts can`t be ruled out. Winds will then diminish
in the late afternoon, becoming westerly in the evening. SCA
seas are likely linger on the ocean for much of tonight.

Marginal small craft conditions are possible in NW flow Tuesday,
possibly lingering on the eastern ocean waters Tuesday night.
Otherwise, sub advisory conditions prevail for mid week during
Wednesday into Thursday.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Dense Fog Advisory until 2 PM EDT this afternoon for ANZ331-
     332-335-340-345-350-353-355.
     Small Craft Advisory until 5 PM EDT this afternoon for ANZ331-
     332-340-345.
     Small Craft Advisory until 6 AM EDT Monday for ANZ350-353-355.

&&

$$

DISCUSSION...MW
AVIATION...JMC/DW
MARINE...MW