Area Forecast Discussion
Issued by NWS Upton, NY

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218
FXUS61 KOKX 082225
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
525 PM EST Mon Dec 8 2025

.SYNOPSIS...
High pressure will build from the west into Tuesday, then weaken
and shift offshore Tuesday night as a weak clipper low passes
to the north. A stronger low approaching on Wednesday will pass
to the north and send a cold front through Wednesday night.
High pressure will then build southeast from the northern
Plains to the Mid Atlantic coast from Thursday into Friday, then
move off the Southeast coast Friday afternoon. Another clipper
low will pass close by Friday night into Saturday morning,
followed by Canadian high pressure this weekend. An Arctic cold
front will move through on Sunday, with strong high pressure
building in on Monday.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Key Point:

* Bitterly cold tonight with temperatures falling into the
  single digits and teens; coldest air since February for most.

Higher cloud deck lingers over the region through this evening
as low pressure tracks away from the Carolina coast, though
this should begin to thin overnight. Closer to home, a 1028 mb
surface high centered near Lake Erie will build over the region,
with winds lightening into this evening as the pressure
gradient relaxes.

The lighter flow could allow for more efficient radiative
cooling overnight, so continued to blend in MOS guidance to
better capture this potential. Either way it will be very cold,
better than 15 degrees below climo, with temperatures falling
back into the single digits inland, and the teens along the
coast. Given the weak winds, wind chills will be close to actual
temperatures and no cold headlines warranted.
Dry conditions prevail.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Key Points:

* Gradual warmup into midweek, with high temperatures back into
  the 40s on Wednesday.

* A couple of quick moving low pressure systems brush or impact
  the area Tuesday night through Wednesday night. Best chance
  for wintry precipitation will be NW of NYC on Wednesday, but
  even these locations should likely change to plain rain.

High pressure over the region shifts offshore on Tuesday, and SW
flow sets up by the afternoon. This will help modify the air
mass in place, first for coastal areas from the marine influence
with ocean SSTs still around 50, then region-wide by Wednesday
with persistent WAA. So while Tuesday remains unseasonably
cold, temperatures climb above the freezing mark into the
mid/upper 30s along the coast by afternoon, with upper 20s
inland.

A more active pattern begins to develop into mid week as a
series of shortwaves move east in the progressive upper flow,
introducing a couple of chances for precipitation. First system
passes through New England Tuesday night, though limited
moisture and weak forcing this far south should keep most dry.
Best chance of seeing any light snow is across southeast CT,
though PoP here sits at only chance (25-30%), and wouldn`t be
surprised if most remain entirely dry. Any coastal precip
could mix with or fall as light rain given marginal boundary
layer temperatures, but again, QPF is light, a few hundredths of
an inch liquid at most.

This first system quickly scoots away north and east, with a
more potent shortwave following behind it Wednesday into
Wednesday night. This will bring a better chance for a more
widespread precipitation, though with a warming column, the
bulk of the precip looks to fall as rain, particularly along the
coast. North and west of NYC, ptype could start out as snow, or
a mix, until the WAA wins out enough to force a changeover to
plain rain. Any accumulation is likely either light or negligible
before the changeover and temperatures Wednesday look to get
into the 40s for most. Wind speeds increase Wednesday afternoon
with the associated LLJ moving overhead, and leaned on NBM 90th
percentile for winds in this period given NBM low bias with
these regimes. After the initial wave, dry slot likely comes in
later Wednesday, and any lingering precip likely tapers as a
light rain as conditions dry out further Wed night behind the
attendant cold frontal passage.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Key Points:

* Temperatures will be at least several degrees below normal
  Thursday through Saturday, then trend even colder early next
  week.

* A clipper low will pass to the south Friday night into
  Saturday morning, with a chance of light snow. This still
  does not look like a significant winter weather event.

It will be brisk and cold Thursday into Friday after a cold
frontal passage, and as the pressure gradient tightens up
between high pressure building to our southwest and low pressure
intensifying over eastern Canada. Winds relax Friday afternoon
as the high moves off the Southeast coast. ECMWF and its
ensemble are consistent on the idea of a clipper low passing to
the south Fri night/Sat but not on its track or strength, with
the 07/12Z cycle showing the low passing just south of the CWA
and delivering a light snowfall capable of meeting advisory
criteria inland, while the 00Z cycle shows northern stream
energy much slower to enter the picture, allowing shortwave
ridging in its advance over Ontario to shunt the low even
farther south, with minimal snowfall. The 08/12Z ECMWF was in
between these two ideas, so less suppressed but still delaying
northern stream energy and lighter on potential snowfall. The
overall idea through Saturday is that northern stream energy
will be too disjointed at that time to be capable of delivering
more than a sub-advisory light snowfall.

Forecast is currently dry and colder for both Sunday and Monday,
with already below normal temps dropping to 10 or more degrees
below normal. However, with the ECMWF in the last few cycles
delaying the arrival of northern stream energy, another
stronger clipper low could bring snow on Sunday, with Arctic air
delayed until Sunday night.

&&

.AVIATION /22Z MONDAY THROUGH SATURDAY/...
High pressure continues to build and settle over the terminals
tonight.

VFR through the TAF period.

N winds diminish through this evening. Winds fall below 10 kt
and become light and variable later in the overnight into
Tuesday morning.

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

No amendments expected.

.OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...

Tuesday afternoon: VFR. SW gusts 15-20 kt late day/evening.

Wednesday: MVFR or lower possible with a chance of rain/snow
across interior Lower Hudson Valley early. Then a chance of
rain during the afternoon and into the evening. S-SW 10-15g25-30
kt possible.

Thursday: VFR. W gusts 20-25 kt.

Friday: Mainly VFR. MVFR possible in any rain or snow showers
late in the day or at night. W gusts around 20 kt.

Saturday: Brief MVFR possible east early, otherwise VFR. W gusts
20-25 kt.

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

&&

.MARINE...
Gusty N winds diminish into this evening. Based on latest buoy
obs showing gusts still over 25 kt at 44025 and likely to
continue for a few more hours, extended SCA E of Fire Island
Inlet until 9 PM. Otherwise, quiet on the waters tonight as high
pressure builds over the region.

A series of clipper systems will then impact the waters Tuesday
night through Wednesday night. A brief period of gales remains
possible on the ocean Tuesday evening and night, before a
better chance of gales develops Wednesday afternoon and evening.
SCA conditions likely on all waters at the least during this
period.

SCA cond likely on all waters Thu into Thu night, with W-NW flow
gusting to 25-30 kt and some gusts on the ocean approaching
minimal gale force. Seas Thu AM start out at 8-11 ft E of Fire
Island Inlet and 5-8 ft W of there, gradually subsiding to 5-6
ft E and 3-5 ft W by daybreak Fri.

Any lull in wind gusts/seas just below 25 kt/5 ft on the ocean
late Fri into Fri night will be short lived, as winds increase
with passage of a low to our south, and cold air advection in
its wake. SCA cond likely on the ocean late Fri night, then
developing on all waters Sat afternoon as flow veers from W to
NW. Some gusts on the ocean once again could approach minimal
gale force Sat night as seas build to 4-7 ft.

&&

.HYDROLOGY...
No hydrologic impacts are expected through the week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 9 PM EST this evening for ANZ350-
     353.
     Small Craft Advisory until 6 PM EST this evening for ANZ355.

&&

$$

SYNOPSIS...BG/DR
NEAR TERM...BG/DR
SHORT TERM...DR
LONG TERM...BG
AVIATION...JE
MARINE...BG/DR
HYDROLOGY...BG/DR