Area Forecast Discussion
Issued by NWS Upton, NY

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767
FXUS61 KOKX 021956
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
356 PM EDT Fri Oct 2 2026

.WHAT HAS CHANGED...
No significant changes overall.

&&

.KEY MESSAGES...
1) The cold front moves through the entire region this evening
and south of Long Island late tonight. Scattered to numerous
showers accompany the cold front with isolated rumble of
thunder possible. Possible brief heavy rain.

2) Next chance of rain Sunday afternoon into Sunday night.

3) Temperatures cooler this weekend and much cooler next week.
Coolest airmass of the season will move in.

&&

.DISCUSSION...
.KEY MESSAGE 1...
The cold front moving in through this evening, while limited
with low level instability will have the aid of an upper jet and
its right rear quad. This will increase synoptic lift along and
behind the cold front. There will also be some positive
vorticity advection in the mid levels along the westerly flow
that moves across.

Showers are still likely for most parts of the region going into
this evening. A brief heavy downpour is possible but most showers
are expected to be light to moderate intensity. Low level
instability will be quite limited and under 500 J/kg. There is a
slight chance of a thunderstorm but thermodynamics are unfavorable.
Model soundings show relatively higher temperatures in 600-500
mb layer, acting as a cap for vertical convective development.

The cold front timing is expected to move across the region
early this evening. For mid to late evening, the front is
expected to have crossed through Southeast Connecticut and
Eastern Long Island. Total rainfall amounts are expected to be
under a half inch with no hydrologic impacts.

Some showers linger behind the cold front across the area heading
into the overnight, especially across for coastal parts. More dry
air enters going into daybreak Saturday with steadily decreasing
dewpoints.

.KEY MESSAGE 2...
The next rain event in the forecast will be within the latter half
of this weekend. This will be from an area of low pressure passing
along a front south of Long Island. This will be the same front that
went through Friday night.

The upper level forcing will be there also with some models
indicating the approach of right read quad of upper jet. In the mid
levels, some forcing is present as well with some positive vorticity
advection ahead of a longer wavelength trough.

The chances of rain are not much different from previously forecast.
There is still quite a spread in the model guidance with the low and
its associated rainfall. There is model run to run variability as
well. However, some model ensemble members continue to show near an
inch of rainfall possible with this event while some others,
including the 12Z Friday operational NAM, have no rainfall.

Want to keep the chance of rain as this is what the consensus of
guidance still indicates with the NBM as well as the LREF mean to
avoid significant forecast changes in POP (i.e. slight chance to
chance or vice versa).

The timing for this will be mainly Sunday afternoon through Sunday
night with the rain tapering off late Sunday night into early Monday.
At this time, forecast amounts are not expected to be significant so
not expecting flooding issues this event.


.KEY MESSAGE 3...
The other main part of the weather story will be lower temperatures
not just this weekend but even more so Tuesday and Wednesday
next week. The main synoptic feature associated with this very
cool air mass is a strong cutoff upper level low moving from
Ontario to Quebec Sunday into Monday. The cutoff upper level low
eventually moves into Canadian Maritimes Tuesday into Tuesday
night.

Area of low pressure passes farther northeast of the region Monday,
followed by a cold front moving through into Monday night. High
pressure builds in from the north and west thereafter into midweek.
The cold core of this airmass will be moving in Tuesday when 850mb
temperatures will be near 0 to 2 degrees C.

Surface high temperatures forecast do not get out of the 60s Tuesday
and Wednesday next week. We also will start to see a lot more 40s
for lows for Monday night, Tuesday night and Wednesday night. For
Tuesday night, that is relatively the coldest night forecast in the
forecast period, with lows ranging from mainly the upper 30s to
upper 40s for the region.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
A cold front will pass through late today into this evening. High
pressure will then follow, passing to the north on Saturday.

Chance of brief MVFR in scattered showers and possibly a tstm with
cold fropa. Non-tstm related gust up to 20 kt also possible with
fropa. Some light showers may linger through about 06Z Sat.

SW winds have been slow to increase but could still gust up to 20 kt
for a time late this afternoon. Winds become NNW less than 10 kt
tonight after cold fropa, then gradually veer N and then NE, with
speeds increasing to around or just over 10 kt after daybreak Sat.

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

Higher confidence on timing of cold fropa and accompanying showers
possibly as early as 22Z but more likely 23Z-01Z. Still cannot rule
out an isolated tstm with fropa.

.OUTLOOK FOR 18Z SATURDAY THROUGH TUESDAY...

Saturday: VFR.

Sunday: MVFR or lower possible with chance of rain in the late
afternoon and evening. Best chance for rain will be at the
NYC metro and coastal terminals. ENE winds G15-18kt in the morning.

Monday: VFR. NW winds 10-15G20kt in the afternoon and evening.

Tuesday and Wednesday: VFR.

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

&&

.MARINE...
SCA is in effect for ocean out 20 nm east of Fire Island Inlet
through this evening. This ends at midnight. This is for ocean
seas near 5 ft and wind gusts near 25 kt. Other waters into this
evening, there could be some occasional 25 kt gusts especially
behind the cold front, but overall sub-SCA conditions should
prevail.

Mainly sub-SCA conditions are expected overnight through Monday
but some SCA potential is there for some of the waters on
Sunday and Sunday night with the low pressure approach.

Outer ocean seas 20-60 nm out are near 4 to 5 ft in marine
forecast through Monday along with wind gusts mostly near 20-25
kt.

A cold front will move across the area waters late Monday. SCA
conditions can be expected from late Monday into early Tuesday
with winds and seas increasing. Right now, SCA conditions appear
likely on at least the ocean, and perhaps all coastal waters.
Conditions improve late Tuesday with sub-SCA conditions for the
middle and end of the week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until midnight EDT tonight for ANZ350-353.

&&

$$

DISCUSSION...JM
AVIATION...Goodman
MARINE...BC/JM