628
FXUS61 KOKX 022344
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
644 PM EST Mon Dec 2 2024
.SYNOPSIS...
Strong Canadian high pressure will gradually build from the west
through Tuesday night. High pressure weakens as it slides off
the Southeast coast on Wednesday. A low pressure system will
push a series of cold fronts through the region as the it passes
to the north into Thursday. High pressure builds back in from
the west Friday and into the weekend. A weak area of low
pressure could skirt just north of the region late this weekend
or early next week.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
-- Changed Discussion --
Some flurries or light snow showers are possible over the next
couple of hours thanks to upper level trough over the region
provides some weak lift and enough instability from daytime
heating. Returns are showing up on radar across northeast NJ,
the Lower Hudson Valley, NYC, SE CT, and Nassau, but are
gradually weakening. As previously mentioned, precipitation
will be light thanks to weak forcing, but also because of the
dry lower levels. Dew point depressions across the area range
from 15 to 25 degrees, so much of what falls will be virga, with
flurries or a light snow shower coming out of the strongest
returns on radar.
With the high to the west, continuing to build in, temperatures
will continue to be below normal for this time of year, though
they are expected to be a bit warmer than last night as winds
are expected to be a bit stronger than last night as the
pressure gradient increases over the region. Teens are expected
across the outlying areas, while lows in the 20s are expected
much elsewhere. Lows around 30 are in store for the NYC area.-- End Changed Discussion --
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
Brisk conditions with winds out of the NW resume again during the
day Tuesday. Temperatures will be similar to Monday with mainly
upper 30s to lower 40s under mainly sunny skies. Slightly
warmer conditions for Tuesday night as compared to Monday night
with lows mainly in the 20s region wide as clouds may offset
prime radiational cooling, though cloud coverage is expected to
be low, with the highest cloud coverage Tuesday night across the
Twin Forks due to the instability as the colder air moves over
the warmer ocean/sound waters.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Key Points
*A clipper low will bring rain and snow showers, along with strong
winds to the area Wednesday night through Friday. Light snow
accumulations are expected across the interior.
*Temperatures run below normal through the weekend, with highs
likely not climbing out of the 30s on Friday and Saturday for most.
Potent shortwave energy diving down from near the North Pole will
aid in deepening a clipper low as it passes over the Great Lakes and
to our north. This low will drag a series of cold fronts through the
area Thursday through Thursday night, along with some rain and snow
showers and strong winds. There have been no major changes in the
12z guidance. The guidance is slowly coming around to show what the
GFS has for the past several runs as far as having the upper level
trough tilt negative just west of the area. This is likely leading
to the upward trend of QPF. However, the system overall still lacks
significant moisture, so total QPF remains under half an inch. The
higher totals continue to be across the eastern half of the area.
NYC and areas north and west have QPF totals closer to a tenth of
an inch.
Temperature profiles appear cold enough across the interior to allow
snow for most if not the entirety of the event, which should lead to
light snow accumulation across the interior. At the coast, a mix of
rain and snow, or simply plain rain, is most likely with surface
temperatures in the upper 30s to near 40. Timing of the bulk of the
showers still looks Wednesday evening and night, gradually tapering
Thursday.
The more impactful weather from this system may end up being the
strong winds and cold air that will be filtering in behind it. With
the region between a 1035 mb high to the west and a 980 mb low to
the northeast, winds will become quite blustery on Thursday,
persisting into Friday. Current forecast has sustained winds peaking
at 20 to 25 mph, with gusts peaking at 35 to near 45 mph. These peak
values will likely be Thursday into Thursday night. Higher gusts are
possible along the coast.
The first push of cold air comes behind the cold front, but there
looks to be a secondary push on Friday. 850mb temps look to bottom
out Friday evening around -12 to -15C. These values are below the
10% moving average for the OKX sounding per SPC`s Sounding
Climatology Page. This should yield highs Friday and Saturday only
in the 30s, with overnight lows in the teens and 20s. A gradual warm
up begins late this weekend, returning conditions to near normal.
High pressure returns from the west by the start of the weekend, and
looks to maintain cold, but mostly dry, conditions. Global guidance
continues to offer differing solutions with the potential of another
diving low out of Canada, and its interaction southern stream
energy. For now, these two features look to remain separate, and the
local region may simply remain dry with high pressure remaining in
place into early next week. Will need to continue monitor trends for
a better handle at this point, but a major system appears
unlikely.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
VFR through the TAF period.
NW winds at 10kt or less tonight, increasing to 10-15kt with
gusts up to 20kt for late Tuesday morning and afternoon.
NY Metro (KEWR/KLGA/KJFK/KTEB)TAF Uncertainty...
An occasional gust 15 to 20 kt possible this evening.
OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
Tuesday Night: VFR.
Wednesday: VFR during the day. Chance of MVFR in snow and/or rain
showers at night. SW winds G15-20 kt.
Thursday: Mainly VFR. Chance of a rain and/or snow shower. W-NW
winds 15-30G35-40 kt.
Friday: VFR. NW winds 15-20G25-35 kt.
Saturday: VFR. W winds 10-15G20 kt.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
A light W to NW flow regime prevails through the first half of
the week.and winds and seas are expected to remain below SCA
levels through Tuesday night.
A Gale Watch is now in effect for all waters as a low pressure
system is expected to bring strong winds. Gale conditions are
possible on the ocean waters as early as Wednesday evening and on
all other waters by Thursday morning. Winds and wind gusts will peak
Thursday afternoon behind the first cold frontal passage. At that
time, sustained winds are forecast to be between 30 and 35 knots
with gusts up to 40 knots. Seas peak on the ocean Thursday afternoon
around 12 to 14 feet. Waves across the central Sound likely reach 5
to 7 feet and a few feet higher for the eastern Sound. Conditions
lower to Small Craft Advisory level by Friday afternoon and then
below SCA level by Saturday. Sub-SCA conditions then expected
through early next week.
&&
.HYDROLOGY...
No hydrologic impacts through early next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Gale Watch from Thursday morning through late Thursday night
for ANZ331-332-335-338-340-345.
Gale Watch from Wednesday evening through late Thursday night
for ANZ350-353-355.
&&
$$
SYNOPSIS...JP/JT
NEAR TERM...JP/JT
SHORT TERM...JP
LONG TERM...JT
AVIATION...JC
MARINE...JP/JT
HYDROLOGY...JP/JT