Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 172046
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
446 PM EDT Fri Oct 17 2025

.SYNOPSIS...
High pressure will gradually build in from the west through
Saturday. A fast moving frontal system passes through the area
Sunday night into Monday. Weak high pressure then briefly
follows Monday night into the first half of Tuesday. Another
frontal system approaches and moves through late Tuesday into
Wednesday, possibly followed by a series of weaker fronts late
in the week.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Gusty N flow will subside tonight as the pressure gradient relaxes
with high pressure building overhead tonight. Clear skies with a
diminishing wind will allow for fairly significant radiational
cooling to occur for interior areas away from the immediate
coastline. This will allow low temperatures tonight to drop into the
middle to possibly low 30s for the northern portions of the CWA. As
a result, Frost Advisories are in effect for these areas. Elsewhere,
there may be some isolated outlying locations, such as the LI Pine
Barrens, that also drop into the middle to lower 30s with some frost
formation, but will not be widespread enough to warrant a headline.
Otherwise, low temperatures in the low to middle 40s are expected
for the immediate coastline and the NYC metro.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
High pressure then remains overhead through the day on Saturday.
This will result in mostly clear skies and a relatively weak wind,
which may be light and variable at times. High temperatures will be
in the low to middle 60s, with some spots for NE NJ and the NYC
metro possibly rising into the upper 60s.

By late day Saturday and Saturday night, high pressure begins to
push offshore with a frontal system approaching from the west. This
will allow a shift in the wind to mainly southerly. This southerly
flow will allow increased surface moisture and slightly warmer air
to move into the area. Increased moisture at the surface and a light
southerly flow will prevent temperatures from dropping too much
Saturday night. Lows will generally be in the  middle 40s to middle
50s, with the warmer spots near the NYC metro and the immediate
coast. Some outlying spots to the northwest may drop into the lower
40s.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Followed consensus / NBM guidance, with the only slight adjustments
to PoP throughout the extended period to account for typical NBM POP
biases.

Key Messages:

* A fast moving frontal system brings brief moderate to heavy rain
  and gusty winds Sunday night into Monday *

The period begins on a dry and increasingly breezy note into the day
Sunday. By the afternoon a S to SW flow increases ahead of the next
approaching system. Towards evening expect rather windy conditions,
more so along the coast and south facing shorelines. The global NWP
guidance continues to show an amplifying trough that approaches
Sunday evening and begins to go negatively tilted into Monday
morning. The ECMWF and EC AIFS appear to no longer be hinting at
cutting off upper level system and keep it moving along later Monday
into Tuesday, which is a change from previous runs. Global
deterministic runs of the GFS, ICON, and CMC are a tad slower, but
not that much different from previous runs. Altogether timing
difference among global guidance appears to have decreased. Thus
PoPs lower late Monday into Monday night with cut off solution off
the table with NWP for the most part.

Behind the main cold FROPA on Monday look for the steadier rain to
shut off with dry advection ensuing. With what looks to be a second
cold FROPA expect a W to WNW wind by Monday afternoon and night
resulting in blustery conditions with dry advection continuing.
Surface ridging briefly works in late at night into Tuesday morning
as high pressure settles well south of the area with mainly sunny
conditions to start. The next frontal boundary approaches late
Tuesday into early Wednesday with a secondary low perhaps forming
along an occluded boundary. The frontal system will likely be weaker
than the frontal system earlier in the period and looks to only
bring the chance of showers Tuesday night into early Wednesday
morning. Otherwise dry and blustery conditions return quickly into
the day Wednesday, followed by a series of trough or weak cold
fronts embedded in the W to NW flow regime. Low end chance PoPs were
carried through for the tail end of the period, although the theme
is for predominantly dry conditions late Wednesday through the
remainder of the period as consensus PoPs appeared a bit high based
on the overall pattern.

Temperatures throughout the period will either be right at, or
slightly above normal despite the passage of multiple cold
fronts.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
VFR conditions through the TAF period with high pressure
in control.

N-NNW winds 10-15 kt this afternoon with gusts around 20 kt
ending. Wind speeds will weaken late afternoon into this
evening, becoming light overnight. Light N-NNW or variable flow
expected Saturday morning, becomes light S-SSW in the afternoon.

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

Occasional gust up to 20 kt possible through 21z

.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...

Saturday Afternoon-Sunday: VFR. SE gusts 20-25 kt possible in
the afternoon and evening.

Sunday night-Monday: MVFR or lower in showers, ending by Monday
afternoon. SW gusts 15-25 kt possible Sunday night becoming W on
Monday.

Tuesday: Mainly VFR. SW gusts 15-20 kt possible.

Wednesday: Mainly VFR. W gusts 20 kt possible.

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

&&

.MARINE...
Light flow with high pressure building in will allow for sub-SCA
conditions through Saturday night.

Small craft conditions develop by Sunday afternoon across the more
SW portions of the coast waters, with these conditions spreading NE
through the remainder of the waters into Sunday night. A period of
gale force wind gusts is looking more likely now for a good portion
of the ocean waters late Sunday night into Monday morning. More
marginal small craft conditions will follow behind the departing
frontal system for late Monday into Monday evening across the non-
ocean waters, with solid small craft conditions continuing on the
ocean through Tuesday, and potentially through the entire mid week
period.

&&

.HYDROLOGY...
No hydrologic impacts expected through the forecast period.

&&

.TIDES/COASTAL FLOODING...
Have issued a coastal flood statement for the So. Nassau south
shore bays as total water levels approach, and may possibly just
touch minor coastal flood benchmarks. Impacts are expected to
be minimal as Stevens guidance has been somewhat biased high in
recent cycles, but does reach minor in So. Nassau in its latest
run for this evening`s high tide. ETSS and ESTOFS are coming in
a bit lower at various gauges, thus not overly concerned at
this point with regard to impacts.

With a strengthening S flow and building seas Sunday into Monday,
there is a chance that some tidal piling and elevated astronomical
tides associated with the new moon of the 20th may lead to some
spotty minor coastal flooding. Steven / IHOPS guidance indicates
75th to 90th percentile reaching or exceeding minor coastal flood
benchmarks for some of the western south shore back bay locations of
LI (mainly Nassau, Queens gauges). If the peak surge lines up with
the time of high tide then the higher percentiles could be realized.
Still plenty of uncertainty this far out as there remains a good
deal of spread in TWL guidance.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Frost Advisory from 11 PM this evening to 9 AM EDT Saturday
     for CTZ005>008.
NY...Frost Advisory from 11 PM this evening to 9 AM EDT Saturday
     for NYZ067>070.
NJ...Frost Advisory from 11 PM this evening to 9 AM EDT Saturday
     for NJZ002.
MARINE...None.

&&

$$

SYNOPSIS...JE/MW
NEAR TERM...MW
SHORT TERM...MW
LONG TERM...JE
AVIATION...DS
MARINE...JE/MW
HYDROLOGY...JE/MW
TIDES/COASTAL FLOODING...