okx-afd on 2024-11-18

973
FXUS61 KOKX 181505
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1005 AM EST Mon Nov 18 2024

.SYNOPSIS...
A weak cold front passes through the area this morning. High
pressure will then move in from the west into tonight and
remain in control through Wednesday. A deep low pressure will
impact the region Wednesday night into the weekend.

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --Forecast on track. The cold front has moved offshore along with
any very light precipitation from earlier this morning. High
pressure will build in with a breezy NW flow today.

Upper low located just north of the Great Lakes based on
the latest GOES-East Water Vapor imagery will slide east into
southern Quebec this morning. The associated trough axis and
weak cold front will move across the area this morning followed
by high pressure slowly moving in from the west through tonight.

Skies will start the day mostly cloudy, but should quickly
become mostly sunny by middle morning, continuing through the
rest of the day. Breezy conditions are expected with NW winds
gusting 20 to 30 mph behind the front into the afternoon. The
downslope flow will help keep temperatures around 10 degrees
above normal with highs reaching the lower and middle 60s. These
readings should remain below any records for November 18.

High pressure will center itself over western NY and central
PA tonight. Winds weaken considerably overnight, especially
along and west of the Hudson River. However, there could still
be a few gusts up to 20 mph across eastern Long Island and
southeast Connecticut due to a lingering pressure gradient from
low pressure near the Maritimes. Lows will range from the middle
30s inland and lower to middle 40s elsewhere.-- End Changed Discussion --

.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
Ridging will remain over the eastern seaboard Tuesday into
Tuesday night. A frontal system associated with a large upper
level low over the Northern Plains will approach Tuesday night,
but weaken as it encounters the ridging. The ridge axis will
begin sliding offshore on Wednesday as the upper low approaches
and deepens. The deepening upper low will send a stronger
frontal system towards the area late Wednesday. The global
deterministic and ensemble guidance is in good agreement on
holding off any rain until Wednesday night, so have kept the
forecast dry through early Wednesday evening.

Temperatures for both Tuesday and Wednesday will be cooler
compared to Monday, but still above normal in the middle to
upper 50s. The usual warmer spots may reach the low 60s on
Wednesday. Lows Tuesday night will range from the middle and
upper 30s inland to the lower and middle 40s elsewhere.

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
Rain overspreads the cwa Wed ngt as a strong h5 low reaches
the Great Lakes. This band comes thru with about an inch of
rain into Thu mrng ahead of the occluded low which should be W
of the cwa. Amounts limited because of the progressive nature of
the band with a 130+kt h3 jet digging into the sern CONUS.
After the initial rain, the colder air overspreads the area from
the SW, and the upr low slows over the Northeast.

There is a high amount of uncertainty with exactly where the upr
low sets up and evolves Thu-Sat, although the influence of the
sys should weaken by Sun per the 00Z GFS/ECMWF. In general
though, the cold pool will set up aloft with periods of pcpn
Thu-Fri and perhaps Sat. Mainly rain, but in this scenario,
interior areas especially those with elevation could see some
snow.

For now, the NBM was followed for temps and pcpn type utilizing
the blended approach. However, this approach will need to be
shelved if this sys does play out as expected attm. High temps
will need to be lowered with maxes across the board Fri and Sat
no higher than the 40s, and likely staying in the 30s some
interior spots. More snow will need to be added as well, with
areas of lift in the quasi isothermal llvls producing some wet
snow.

.AVIATION /15Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --Weak high pressure slowly builds in from the west.

VFR. Winds have become NW with gusts 20-25 kt expected to
develop between 15-18z. Gusts will diminish in the early
evening, but the NW flow will continue into Tue morning.

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

Occasional gusts to around 20kt possible til 16Z.

OUTLOOK FOR 12Z TUESDAY THROUGH FRIDAY...

Tuesday...VFR.

Wednesday...VFR.

Wednesday Night...MVFR/IFR with rain developing and E-SE gusts up to
35kt.

Thursday...MVFR/IFR with rain in the morning, then mostly MVFR in
the afternoon with a chance of rain. Gusts up to 35kt possible with
direction becoming W in the aftn.

Friday...Mainly MVFR with gusty W winds.

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

.MARINE...
No changes were made to the SCA for this afternoon into
tonight. NW flow will increase this morning behind a cold front
passage leading to gusts around 25 kt this afternoon through
much of tonight. These gusts will be most frequent on the ocean,
Long Island Bays, and eastern Long Island Sound. Winds should
begin to weaken below SCA levels on the Long Island Bays and
eastern Long Island Sound by midnight, but should linger through
day break on Tuesday. Seas should remain below 5 ft. The
gradient will relax on Tuesday with winds and seas below SCA
levels through Wednesday.

SCA cond along with possible gales for Wed ngt and Thu as deep low
pres sets up W of the waters. Although the main sys will gradually
weaken Fri and Sat, SCA cond likely with the low slow to exit.

.FIRE WEATHER...
NW winds less than 10 mph early this evening become light
westerly later this evening and overnight. Monday, with the
passage of a cold front northwest winds increase to 10 to 15
mph, gusting 20 to 30 mph by Monday afternoon. Minimum RH will
range from 40 to 45 percent across the Lower Hudson Valley into
interior southern Connecticut, and 35 to 40 percent along the
coast but down to 30 to 35 percent for portions of NE NJ.

.HYDROLOGY...
Dry conditions will continue through Wednesday afternoon.
Around 1-1.5 inches of rain is expected Wed night and Thursday.
Additional light to moderate areas of precip are possible
Friday and Saturday. No hydrologic impacts are expected.

.TIDES/COASTAL FLOODING...
-- Changed Discussion --Extended the Coastal Flood Statement until 11 am for
southeastern Long Island as water levels may continue to rise
with high tide at 1017 am this morning for Montauk.

Astronomical tides will continue decreasing early this week.
However, there still may be some lingering surge from offshore
low pressure. This should lead to one more round of minor
coastal flooding for the south shore back bays of Nassau/Queens
and coastal Fairfield County with high tide this morning/early
afternoon. Coastal Flood Advisories remain in effect. Any other
minor coastal flooding will be localized and mainly confined to
the lower NY Harbor, coastal Westchester, and the south fork of
Long Island (Shinnecock Bay and Fort Pond Bay). Coastal flood
statements remain in effect for these locations. No additional
coastal flooding is expected through the middle of the week.-- End Changed Discussion --

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --CT...Coastal Flood Advisory until 2 PM EST this afternoon for
CTZ009.
NY...Coastal Flood Advisory until 11 AM EST this morning for NYZ178-
179.
NJ...None.
MARINE...Small Craft Advisory until 1 AM EST Tuesday for ANZ332-340.
Small Craft Advisory until 7 PM EST this evening for ANZ345.
Small Craft Advisory until 6 AM EST Tuesday for ANZ350-353-355.-- End Changed Discussion --

SYNOPSIS...JMC/DS
NEAR TERM...JP/DS
SHORT TERM...DS
LONG TERM...JMC
AVIATION...BC/JMC
MARINE...JMC/DS
FIRE WEATHER...
HYDROLOGY...JMC/DS
TIDES/COASTAL FLOODING...