Area Forecast Discussion
Issued by NWS Upton, NY

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298
FXUS61 KOKX 180025
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
825 PM EDT Fri May 17 2024

.SYNOPSIS...
Weak high pressure remains over the region into Saturday night.
A weakening trough of low pressure approaches from the west and
dissipates by Saturday evening. Otherwise, high pressure
generally remains in control through the middle of next week. A
cold front approaches late in the week.

&&

.NEAR TERM /THROUGH TODAY/...
Forecast on track this evening.

A northeast to east flow will bring low level moisture into
region tonight into Saturday morning. And with some weak low
level convergence and lift light drizzle will be possible.
Meanwhile, a weak surface trough will be moving very slowly east
and weaken tonight into Saturday. And by Saturday morning a few
showers may move into the western portion of the region with
some weak lift with the trough. The offshore low weakens
Saturday afternoon with lift ending, so end the chances for
drizzle by then.

With little airmass change overnight temperatures will be
similar tonight to Friday morning`s lows. And with more clouds
and the easterly flow high temperatures Saturday will be around
5 degrees below seasonal normals.

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...
The weakening surface trough to the west may move into the
region, and into the surface ridge, and then dissipate Saturday
night. Any lift and showers with this system will then be
ending. Otherwise, weak high pressure remains in control.
Once again with little airmass change temperatures Saturday
night will be in the lower to mid 50s across the region.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
*Key Points*

*Mainly dry with above temperatures Sunday through next week.

*A cold front approaches late in the week with the next chance at
showers, possibly thunderstorms, Wednesday night through Thursday.

Relatively quiet weather is expected Sunday through the middle of
the week. Ridging both aloft and the surface will begin building
over the northeast on Sunday and should remain in control through
Wednesday. The modeling continues to signal the break down of the
ridge late Wednesday as an upper level trough heads east from the
Rockies towards the Great Lakes. There is relatively good agreement
for this shortwave to move across the region sometime late in the
week. However, the guidance is not in agreement on its amplitude and
timing, which impacts the strength of a cold front. This cold front
should approach late in the week bringing an increase in chances for
showers and possibly Thunderstorms. Will continue to use the NBM
given the time range, which looked reasonable for PoPs Wednesday
night into Thursday night. The consensus indicates the front should
be moving through on Thursday, but this could speed up or slow down,
especially with uncertainty with the aforementioned trough and
weakening of the ridge.

Mainly used the NBM deterministic for temperatures, but blended in
the 50th percentile for Monday through Thursday. There is a fair
amount of temperature spread, and the NBM deterministic is lying
closer to the 25th percentile. This is most prominent away from the
immediate coast where temperatures typically are warmer during
onshore flow days. The onshore flow should keep coastal locations in
the upper 60s to lower 70s, but elsewhere should be able to warm
into the upper 70s and lower 80s. Temperatures could be even warmer
(middle to upper 80s away from the coast), especially if the flow
takes on a more westerly component ahead of the front Wednesday or
Thursday.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
Weak high pressure will be in place through Saturday.

VFR through this evening. MVFR ceilings will return late
tonight across the eastern terminals (KGON, KISP, and KBDR).
Chances for MVFR ceilings have lowered for points west. Have
removed MVFR ceilings for the city terminals, and went with
TEMPO group instead.

Winds become light and variable for a short time tonight. Winds
then prevail mostly NE overnight. Winds remain mostly NE 5-10kt
on Saturday into Saturday night.

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

Uncertainty exists in how far west MVFR ceilings reach late
tonight into Saturday morning.

OUTLOOK FOR 00Z SUNDAY THROUGH WEDNESDAY...

Saturday Night: Mainly VFR. MVFR for eastern terminals.

Sunday...VFR. MVFR or lower could persist
at the eastern terminals all day.

Monday...VFR

Tuesday-Wednesday...VFR.

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

&&

.MARINE...
Ocean seas east of Fire Island Inlet remain elevated, at 5 to 6
feet, with a east to southeast 8 second swell from weak low
pressure meandering south of Nova Scotia. The low weakens
further during Saturday. Ocean seas will take awhile to subside,
and have extended the SCA from Fire Island to Moriches Inlet
until midnight, and to the east of Moriches Inlet until 1000 AM
Saturday. Then Saturday afternoon and Saturday night winds and
seas remain below advisory levels. On the non ocean waters winds
and seas remain below advisory levels tonight through Saturday
night.

A weak pressure gradient over the waters will lead to conditions
below SCA levels Sunday through the middle of next week.

&&

.HYDROLOGY...
There are no hydrologic issues through the middle of next week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 10 AM EDT Saturday for ANZ350.
     Small Craft Advisory until midnight EDT tonight for ANZ353.

&&

$$

SYNOPSIS...DS/MET
NEAR TERM...DS/MET
SHORT TERM...MET
LONG TERM...DS
AVIATION...JP
MARINE...DS/MET
HYDROLOGY...DS/MET