Shelter Island, New York Weather Forecast Discussion

192
FXUS61 KOKX 040002
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
802 PM EDT Fri Oct 3 2025
.SYNOPSIS...
High pressure will remain over the region through early next
week. A cold front will then approach Tuesday night into
Wednesday, then move through by early Thursday. Strong high
pressure will follow from the west later Thursday through
next weekend.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
High pressure remains across the region tonight but its center
will be moving farther south of the region. A low level SW flow
will be in place, becoming W overnight. Ridging aloft
approaching the region will keep subsidence strong, allowing for
clear skies. Across the interior, winds become very light to
calm. Radiational fog is forecast along interior river valleys
and outlying interior locations especially where fog occurred
the previous morning. No fog expected along the coast with
boundary layer winds staying up and allowing for more
vertical mixing.
Used MAV/MET/NBM for forecast low temperatures along the coast
and MAV/MET inland. Expect a vast range of lows, from the mid
40s across parts of the interior to near 60 in NYC.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
For this weekend, a ridge of high pressure will be in control,
keeping dry weather and mostly clear sky conditions. With the
center of the high pressure area moving farther south, a more SW
low level flow will develop and advect warmer air into the
region Saturday. The 850mb temperatures are forecast to rise a
few degrees Saturday afternoon and maintain nearly the same
values on Sunday afternoon. The high temperatures are expected
to be noticeably warmer than the Friday high temperatures and
will be well above normal for this time of year.
Noting the forecast guidance leaning towards higher than the
mean with forecast temperatures, used the NBM 90th percentile
for high temperatures both Saturday and Sunday. The high
temperatures will be very similar for both days despite a more
onshore component to the surface wind on Sunday. Expecting a
majority of the region to have high temperatures within the
range of low to mid 80s for both Saturday and Sunday. The Twin
Forks of Long Island as well as some portions of other
coastlines have high temperatures forecast more in the mid to
upper 70s.
For Saturday night into early Sunday morning, with winds
becoming very light across the entire region, used a blend of
MAV/MET for low temperatures to better capture radiational
cooling. With forecast increases in dewpoints, more fog is
forecast as well including inland and some locations along the
coast. Did not put into forecast yet, but patchy fog will be
possible again for late Sunday night into early Monday morning
for some locations with similar environment and efficient
radiational cooling expected once again.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
NBM was largely followed with only minimal changes.
Key points:
* High pressure remains in place in the area through Tuesday.
* A frontal system approaches the area Tuesday night, eventually
  moving through during the day on Wednesday. Model guidance varies
  a bit with timing but frontal passage expected to move through the
  area by Wednesday night. Main concern in a period of light to
  moderate rainfall. Thunder not anticipated, but not completely
  ruled out.
* Another strong high pressure system builds in from the west
  thereafter and into next weekend.
* Temperatures will be anomalously warm Monday and Tuesday with
  highs in the middle 70s to low 80s, about 10-15 degrees above
  average. Temperatures drop to near normal for Wednesday.
  Temperatures then drop below normal Thursday and into the weekend
  with highs in the low to middle 60s.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
VFR as high pressure remains over the area.
S-SW sea breezes have picked up at some terminals near the
coast, expect these to diminish by 02Z. Light SW-W flow
overnight should become WNW after daybreak. S-SW sea breezes
close to 10 kt should develop along the CT coast during late
morning, then at KJFK/KISP by 18Z and the rest of the NYC metros
in the late day hours.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled AMD expected.
.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
Saturday through Tuesday: VFR.
Tuesday night and Wednesday: MVFR with showers likely. NW winds
G15-20kt on Wed, becoming N late in the afternoon.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Sea may build to 4 ft on the ocean waters tonight, just below
advisory threshold of 5 ft. Sub advisory conditions are
expected through Tue morning with high pressure in control.
Overall pressure gradient should become relatively weak.
There may be a few gusts that approach 25 kt on the ocean waters
Tue afternoon ahead of a cold front.
&&
.HYDROLOGY...
Total rainfall from the frontal passage next week may be 1/2 to
1 inch. This rainfall will be beneficial, so there are no
hydrologic concerns attm.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JM/MW
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...MW
AVIATION...BG
MARINE...JM/MW
HYDROLOGY...JM/MW

NWS OKX Office Area Forecast Discussion