Middle Island, New York Weather Forecast Discussion

395
FXUS61 KOKX 191946
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
346 PM EDT Fri Sep 19 2025
.SYNOPSIS...
High pressure builds across the region through Saturday, then
moves farther northeast for the rest of the weekend into early
next week, getting farther out into the Atlantic. A warm front
lifts to the north on Tuesday as high pressure weakens nearby. A
cold front then passes through on Wednesday. High pressure
tries to build back in thereafter.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Mid level ridge starts to build in from the west. Surface high
pressure will continue to build in from the north tonight.
There will not be as effective radiational cooling tonight due to
increasing NE winds. However, there will be low level cold air
advection to compensate. The resulting lows are expected to be lower
than the previous night. Still using colder of MOS for the interior
areas along with NBM since interior areas have nearly calm winds and
there are mostly clear sky for the entire area. Used 2/3 MAV and 1/3
NBM combination for the temperatures, ranging from the mid 40s
to around 60.
Along with the cold air advection, drier air is advecting into the
region also, and with enough separation between temperatures and
dewpoints, no fog is expected.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
Mid level ridging continues Saturday with the ridge axis moving
across Saturday night.
Surface high pressure shifts to the east Saturday, eventually
reaching Northern New England Saturday night. This will keep an
easterly flow across the local region.
For Saturday, model 850mb temperatures expected to continue to lower
from morning into early afternoon before increasing a little mid
afternoon into early evening. The more easterly winds will make for
a cooler day with high temperatures only in the lower 70s for
much of the region with localized mid 70s despite mostly sunny
sky conditions. Kept NBM for the max temperature forecast.
For Saturday night, the winds will weaken across the interior and
with mostly clear sky conditions continuing. There is some low level
moisture increase as there is some model indication of slightly
rising dewpoints Saturday night into early Sunday morning with
otherwise dewpoints remaining nearly constant. There will be an
environment that could more easily become saturated at the low
levels. A blend of MOS with NBM used to capture radiational cooling
better as winds will become more light with a mainly clear sky.
Where winds will be light (much of the interior as well as much
of Southern CT), have patchy fog forecast late at night into
early Sunday morning. Winds stay up across coastline and NYC as
well as Long Island to prevent fog formation there.
Used the MAV/MET/NBM combination for temperatures, ranging from
the mid 40s to upper 50s.
For the rest of the weekend, mid level negative geopotential
tendency as ridge moves east and a quasi-zonal flow sets up. Surface
high pressure will gradually move near Nova Scotia Sunday and then
east of Nova Scotia Sunday night, getting farther out into the
Northern Atlantic.
Would expect more clouds Sunday into Sunday night compared to the
first half of the weekend. The easterly flow continues but weakens
Sunday night. Still have some patchy fog but not as much as the
previous night. High temperatures trend cooler for Sunday
(upper 60s to lower 70s) compared to the previous day but
slightly warmer for the low temperatures Sunday night (mostly
upper 40s to upper 50s) compared to the previous night.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
NBM was followed with only a few minor changes to PoPs.
Key Points:
*Below 50% chance of showers for each period Tuesday through Friday.
Highest overall chances occurring Tuesday afternoon through
Wednesday in association with a cold front passage. No hydrologic
impacts anticipated.
*High temperatures generally in the 70s, except in the low 80s on
Tuesday for the typically warmest spots.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
High pressure continues to build in from the northwest through
Saturday.
VFR.
Generally a NW flow into early this evening then veers to a
more northerly flow, and diminishes. Occasional gusts may
continue through 21Z. Wind then become more NE late tonight
into Saturday morning, likely increasing a few kts. And toward
18Z Saturday winds become E.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled amendments expected.
.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
Saturday afternoon - Monday: VFR.
Tuesday: MVFR possible with chance of showers in the afternoon
and evening. A thunderstorm is also possible.
Wednesday: MVFR possible with a chance of showers.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Sub-SCA conditions are forecast to remain on the area waters
through the weekend. Portions of the ocean may reach 25 kt for
wind gusts occasionally early Saturday with the pressure
gradient setting up between higher pressure to the north and
lower pressure to the south. Otherwise, max gusts on the waters
this weekend will be 20 kt. Seas at times this weekend on the
ocean are forecast to reach 4 ft. So, conditions on the ocean
get close but stay below SCA thresholds.
A SE swell brings the likelihood of marginal small craft conditions
on the ocean starting Monday, with a higher likelihood of more
widespread 5 ft seas on Tuesday, possibly lasting through
Wednesday.
&&
.HYDROLOGY...
There are no hydrologic concerns through the entire forecast
period.
&&
.TIDES/COASTAL FLOODING...
The rip current risk for the rest of today remains low. NE to ENE
winds at 10-15kt winds may be just enough to create longshore
currents on Saturday, producing a moderate risk. A better chance of
longshore currents occurs on Sunday with easterly winds at 10-15kt.
The risk likely remains moderate through the day.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JM
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...DR
AVIATION...MET
MARINE...JM
HYDROLOGY...JM
TIDES/COASTAL FLOODING...

NWS OKX Office Area Forecast Discussion