544
FXUS61 KOKX 031148
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
648 AM EST Tue Dec 3 2024
.SYNOPSIS...
High pressure building into the Tennessee Valley will be in control
through tonight and early Wednesday. Low pressure moves north of the
area and drags a warm front through Wednesday night, followed by a
pair of cold fronts into Thursday. High pressure builds back in from
the west Friday and into the weekend, sliding offshore Sunday. An
area of low pressure may then approach the region early next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
For this update just tweaked hourly forecast database for the
next few hours to better account for latest conditions and
observational trends. Mainly adjusted sky cover as patches of clouds
are moving across coming out of the NW.
Brisk conditions with winds out of the NW resume again during today.
Temperatures will be similar to the previous with mainly upper 30s
to lower 40s under mostly sunny skies, with some scattered clouds at
times further northwest. Towards late in the day and early this
evening some of the higher res guidance is suggestive of some
moisture at around the 800 mb level streaking in from the WNW
downwind of the Great Lakes. Any clouds that survive into the area
may produce a few flurries, especially for northern and northeastern
portions of the area. The HRRR has been suggestive of this on some
of its recent runs. No sensible weather impacts are expected with
only a few flakes at most.
For tonight expect similar conditions compared to the previous night
with lows mainly in the 20s region wide, with a few upper teens
draped across the northern tier of the CWA. Dew points will remain
primarily in the upper teens to around 20 as dry and brisk
conditions will continue to prevail under mainly clear skies.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
During Wednesday morning high pressure to the southwest of the area
gets further to the east. Towards late morning and the early
afternoon a return flow starts to get established, especially
further east. This will result in a SW flow picking up during the
afternoon, especially for southern coastal sections. Temperatures
for the afternoon likely reach close to 50 across far eastern
portions of the area, with some colder upper 30s and lower 40s
further to the northwest. Clouds will increase quickly during the
late morning and afternoon in advance of the next storm system which
approaches from the west. The system actually will eventually move
north of the area Wednesday night into Thursday morning as the
system tracks across the Northern Great Lakes and moves into
Southern Canada towards early Thursday morning. A potent mid level
shortwave will swing through as a warm front will emanate from the
low and moves across Wednesday night. This will provide much of the
lift in tandem with a spoke of mid level energy with a potent vort
max swinging through. Precipitation breaks out from west to east
Wednesday evening / night with mainly snow across northern and
northwestern sections, with a wintry mix getting closer to NYC and
NE NJ, with mostly rain across south central / southeastern CT, and
LI. A few hundredths further west, to as much as a half inch of
liquid is expected across eastern most sections towards sunrise
Thursday morning. By early Thursday morning a coating to an inch of
snow is a possibility for northern and northwestern portions of the
area, with mainly wet conditions further south and east.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
Key Points
*A clipper low will bring rain and snow showers, along with gusty
winds, to the area Thursday through early 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.
The parent low works through northern New England during the day as
an attendant cold front pushes through the local area. The rain and
snow showers largely wind down by late Thursday morning. A few
showers could linger into late day or early evening, but coverage
looks isolated to scattered at best.
Perhaps more impactful than the precipitation, colder air and gusty
winds develop on the backside of the system. With the region between
a 1035 mb high to the west and a deepening 990 mb low to the
northeast, these winds likely persist into Friday. Soundings prog
deep mixing above 850 mb Thursday, and winds aloft there as high as
50 kt. Closer to the surface, sustained winds likely peak 20 to 25
mph, with gusts up to 40 or 45 mph, mainly Thursday and Thursday
evening. Slightly higher gusts are possible along the immediate
coast, but as of now, appears shy in strength and coverage to reach
advisory criteria.
Temperatures likely fall Thursday afternoon as colder air quickly
begins to advect in behind the front. Coupled with the blustery
conditions, wind chill values may be in the 20s region wide by late
day. A few flurries or snow showers are possible even down to the
coast late into early evening Thursday as the colder air mass begins
to work in, but no additional accumulation is expected.
The first push of cold air comes behind the cold front, but there
looks to be a secondary on Friday. 850 mb temps fall to -12 to -15C,
which should yield highs Friday and Saturday only in the 30s, with
overnight lows in the teens and 20s. NW flow on Friday should
continue to gust 30 to 35 mph, and will keep wind chills in the 20s
much of the day, if not lower. High pressure returns from the west
into the weekend and winds lighten, with the high shifting over the
Southeast and offshore by Sunday. This should allow a WSW or SW flow
to develop and begin a gradual warm up into early next week. Still
model differences with northern stream energy passing through the
Great Lakes, and any potential interaction with a shortwave swinging
through the South. For now, capped PoPs on Monday and thereafter at
50% given the varying solutions.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
VFR through the TAF period.
NW winds at 10 kt or less into the morning push, increasing to 10 to
15 kt with gusts up to 20 kt late this morning and afternoon. Winds
and gusts subside this evening, and direction becomes westerly
overnight into Wednesday morning. Flow backs SW into early Wednesday
afternoon as speeds begin to quickly increase 10-15G20kt.
NY Metro (KEWR/KLGA/KJFK/KTEB)TAF Uncertainty...
Winds are expected to prevail at or north/right of 310 magnetic for
KJFK and KLGA, but may be south of it at times late this afternoon.
OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY...
Wednesday: VFR during the day. Chance of MVFR in snow and/or rain
showers at night. SW winds G20-25 kt developing by late day.
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 NW flow regimes continues today into tonight. For later this
afternoon into a portion of tonight a few gusts get to around 20 kt
or thereabouts for a portion of the nearshore and ocean waters.
Otherwise sub advisory conditions should prevail through tonight and
into a good portion of Wednesday. During Wednesday the winds switch
around to more of a SW direction. By the afternoon small craft
conditions develop on the ocean waters and potentially for the south
shore bays of LI by late in the day. Gale conditions then take shape
on the ocean and extreme eastern portions of LI Sound during
Wednesday night, with small craft conditions for the majority of the
non-ocean waters going over to gales by Thursday morning. The winds
will peak Thursday afternoon behind another 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 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 early Saturday. Sub-SCA conditions then expected
through early next week.
&&
.HYDROLOGY...
No hydrologic impacts are anticipated through early next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 6 PM Wednesday to 6 AM EST Thursday
for ANZ331-335-338-340-345.
Gale Watch from Thursday morning through late Thursday night
for ANZ331-335-338-340-345.
Gale Watch from Wednesday evening through late Thursday night
for ANZ332-350-353-355.
Small Craft Advisory from 1 PM to 6 PM EST Wednesday for
ANZ350-353-355.
&&
$$
SYNOPSIS...JE/DR
NEAR TERM...JE
SHORT TERM...JE
LONG TERM...DR
AVIATION...DR
MARINE...JE/DR
HYDROLOGY...JE/DR