334
FXUS61 KOKX 310132
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
832 PM EST Mon Dec 30 2024
.SYNOPSIS...
Weak high pressure briefly builds into the region overnight. Low
pressure over the Ohio Valley on Tuesday will then track up into
eastern Great Lakes Tuesday night, sending a frontal system and
secondary low across the area. The secondary low slowly deepens
on Wednesday tracking northeast along the New England coast.
The area then remains in between low pressure to the north and a
building high to the south through the weekend. Another frontal
system may approach the area early next week.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A weak area of high pressure builds in from the southwest
overnight with skies clearing. WSW winds may occasionally gust
up to 20 mph this evening, especially near the coast. Winds
will then gradually diminish overnight.
Temperatures remain mild for year`s end, generally remaining at
or above the freezing mark everywhere into early morning.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/...
An active pattern to ring in the new year.
As a potent shortwave trough swings east through the Midwest on
Tuesday, the surface frontal system treks through the Ohio Valley,
and its associated warm front approaches the local region Tuesday
evening. The primary surface low slowly weakens over the lower
Great Lakes region, while a secondary low forms near NJ Tuesday
evening as upper level energy with the shortwave continues on
toward the coast. Rain showers quickly overspread the region
Tuesday evening, generally after 21Z, and could fall heavy at
times, at least briefly. 12Z HREF guidance indicates the potential
for hourly rates as high as between a half and one inch per hour,
which could cause brief nuisance flooding in typical urban and
poor drainage areas. The progressive nature of the system should
mitigate flash flood concerns or anything more significant.
Isolated rumbles of thunder also cannot be ruled out, with
soundings highlighting the potential for weak elevated instability
as the primary low passes to the west. The window for this threat
looks to be generally between 2Z and 8Z Wed. The rain tapers
toward daybreak as the whole system pushes into New England, and
the majority of the region should awake to dry conditions Wednesday.
Lingering showers, especially across the interior, are possible
through the day Wednesday as the trough moves through, though
coverage looks more spotty.
The tightened pressure gradient with the deepening low and building
high pressure will allow for a blustery day. Westerly gusts up to 35
mph look likely by the afternoon, with isolated gusts a bit higher
possible. Temperatures both Tuesday and Wednesday remain fairly
mild, with highs both days in the upper 40s and lower 50s.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Key Points:
* Windy conditions expected Thursday in the wake of a departing low.
* Below average temperatures expected during much of the extended
period.
The area will remain positioned south of the departing low that
continues to strengthen and occlude in southeastern Canada Thursday
into the end of the week. Meanwhile, subtle ridging over the Central
US will allow for a surface high pressure system to shift into the
Southeast US. This will result in a persistent NW flow through the
end of the week and into the weekend.
The most notable day looks to be Thursday where a tight pressure
gradient in the wake of the low will allow for substantial BL mixing
in NW flow. The deep low level mixing will result in strong and
gusty winds to develop Wednesday night into Thursday. Sustained
winds of 15-20 mph with gusts upwards of 35-40 mph will be
likely during this time frame. It`s possible that wind gusts may
be locally higher. Temperatures Thursday will be seasonable
with highs in the upper 30s to low 40s, but strong wind will
likely bring wind chills during the day down into the 20s and
low 30s.
Continued NW flow persist Thursday night and into Friday, though a
gradual decrease in strength is expected as the pressure gradient
relaxes a bit as the occluded low weakens and moves further away
from the area. Thereafter, the decreasing temperatures through the
weekend are the most notable sensible weather feature. Highs Friday
will be in the middle to possibly upper 30s. Temperatures continue
to decrease into the weekend with highs both Saturday and Sunday
peaking out only in the low to middle 30s.
Regarding any precipitation chances, much of the long term is
expected to remain mostly dry and mostly to partly cloudy. The next
chance for any substantial precipitation will be early next week
where a frontal system may approach from the west late Sunday and
into Monday, though any details regarding placement, intensity, and
timing are very uncertain at this time.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
Weak high pressure builds in from the southwest overnight and
then quickly gives way to a frontal system approaching from the
southwest on Tuesday. A secondary low develops just southwest
of the area early Tuesday evening and then moves quickly across
the area at night.
VFR is expected to prevail through 00Z Thursday. Conditions
then quickly deteriorate lowering to MVFR/IFR with about a 3-4
hour period of moderate to heavy rain.
SW-W winds overnight will generally be 10 kt or less. However,
for the first half of the night there will be occasional gusts
up to 20 kt, mainly at the coastal terminals. Winds will gradually
diminish late tonight into Tuesday morning, backing around to
the SE/E at 5-10kt Tuesday afternoon, and then increasing 10-15kt
G20kt at the coastal terminals in the evening.
...NY Metro (KEWR/KLGA/KJFK/KTEB)TAF Uncertainty...
Winds may vary overnight from 220-250, especially the first part
of the night.
Timing of wind shift on Wednesday may vary by 1-2 hours.
Amendments likely Tuesday night with the onset of rain and
lowering cigs/vsbys.
OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
Tuesday Night: IFR/MVFR likely in rain, isolated TSRA. Rain
Wednesday: MVFR or lower with chance of -RA in the morning,
improving to VFR in the afternoon. Chance of -SHRA at KSWF in
the afternoon. W winds G25-30kt. Occasional gusts up to 35 kt.
Thursday: VFR and very windy. W winds G25-35kt. Occasional
gusts up to 40 kt. Gusts decrease at night to closer to 20 kt.
Friday and Saturday: Mainly VFR. W winds G20kt. Gusts up to 25
kt possible.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
SCA remains in effect for all waters but the NY Harbor and South
Shore back bays into early evening. WSW gusts up to 25 kt lightens
after sunset on all waters and the Advisory for remaining non ocean
water zones is set to expire early this evening. Ocean seas at or
above 5 ft however should linger tonight into Tuesday, and increase
once again Tuesday evening ahead of approaching low pressure.
Extended the SCA on these ocean waters thru 11Z Wed, though
strengthening winds behind the system will require an extension
likely through Thursday and expansion to non ocean waters once
again.
A Gale Watch is now in effect for the ocean waters starting
Wednesday. There is potential for gale force gusts on all other
waters as well starting Wednesday night. NW winds with gusts
upwards of 30-35 kt on the sheltered waters with gusts upwards
of 40kt possible on the ocean with wave heights 7-10 feet.
SCA conditions may persist for the waters into early Friday before
dropping off for the sheltered waters as winds relax. SCA persist on
the ocean for wind gusts and wave heights through at least Friday
night.
&&
.HYDROLOGY...
A band of moderate to heavy rain showers Tuesday evening and night
could cause brief minor nuisance flooding of urban and poor drainage
areas.
There are no other hydrologic concerns through the weekend.
&&
.TIDES/COASTAL FLOODING...
Water levels for the south shore bays of wrn Long Island/Queens and
the SW CT/Westchester coastline may approach minor thresholds with
Wed AM`s high tide cycle.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EST Wednesday for ANZ350-353-
355.
Gale Watch from Wednesday morning through Thursday afternoon
for ANZ350-353-355.-- End Changed Discussion --
&&
$$
SYNOPSIS...DR/DW/MW
NEAR TERM...DR/DW/MW
SHORT TERM...DR
LONG TERM...MW
AVIATION...DW
MARINE...DR/JT/MW
HYDROLOGY...DR/MW
TIDES/COASTAL FLOODING...