-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 182335
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
735 PM EDT Thu Apr 18 2024

.SYNOPSIS...
A weak wave of low pressure south of Long Island will drift
southeast and farther out to sea as high pressure noses down
from eastern New England and the Canadian Maritimes. The high
will weaken on Friday as a cold front approaches from the west.
The front will move through late Friday night into early
Saturday, followed by a dry secondary cold frontal passage late
day Saturday or Saturday evening. High pressure will then follow
from Saturday night into early next week. A weak frontal system
will impact the region mid week.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Only minor tweaks with this update, mainly to refine the time of
drizzle/light showers which are continuing to exit eastern
portions of area and will be gone within the next several
hours.

Somewhat blocky pattern noted, with a series of omega blocks
stretching from the NE Pacific all the way to wrn Europe, but
with enough of a zonal jet across the Pacific and CONUS to the
south to keep things somewhat progressive. A weak shortwave
trough riding through an associated upper ridge over the
Northeast will move east by this evening and bring an end to
showers/drizzle mostly across Long Island and S CT, with some
leftover patchy fog in spots. Skies will remain cloudy in the
wake of this wave as moisture remains trapped beneath a
subsidence inversion associated with the upper ridge. Low temps
tonight per MOS guidance blend should be in the upper 30s inland
and lower 40s along the coast and in the metro area.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY/...
The sfc high will hang in early Fri morning, then slowly weaken
and move east in the late morning and afternoon, with an onshore
SE-S flow developing in the afternoon. A cold front begins to
approach late Fri afternoon and should move across Fri night
with showers, especially inland during the first half of Fri
night (likely PoP), then across Long Island and S CT later Fri
night (likely/cat PoP) as better low level thermal and moisture
advection develops along the coast.

After some lingering AM showers mainly across ern Long Island
and SE CT in the morning, dry conditions expected for Sat, with
some partial sunshine developing. Downslope gusty W-NW flow and
deep mixing to 750 mb late in the afternoon should allow temps
to rise into the 60s throughout, possibly approaching 70 in
urban NE NJ if not a little warmer just ahead of an approaching
dry cold front late in the day.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
High pressure will continue to build into the region through the
second half of the weekend and remain in control of the weather
through Tuesday with a zonal pattern and weak troughing pattern
aloft.

Cold air advection will lead to cooler temps Saturday night into
Sunday. Saturday night lows will be in the mid 30s to mid 40s,
followed by highs on Sunday in the upper 50s/lower 60s. This
looks to warm up thereafter with highs mostly into the 60s on
Monday and Tuesday. Sunny skies are expected for much of Monday
and Tuesday aided by high pressure.

A 500 mb trough shifts through the Great Lakes on Tuesday, with
an associated weak surface low and cold front as it moves into
NE Canada Wednesday into Thursday. Rain chances increase on
Wednesday as this system moves across. Drier weather returns
for Thursday. Temperatures fall back to a degree or two below
normal behind the cold front on Thursday.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
Weak low pressure was southeast of the terminals this evening
with high pressure building in from the north behind the low.
High pressure builds late tonight then moves off the northeast
coast Friday afternoon as a cold front approaches to the west.

MVFR conditions will continue to improve to VFR from the east
to west through this evening, with KGON already VFR. However,
MVFR may linger into late tonight at KTEB and KSWF. Timing of
improvement is uncertain, and may be 1 to 3 earlier than
forecast.

Showers may move into the western terminals late Friday
afternoon, earlier than forecast. However, conditions likely
remain VFR until toward 00Z Saturday.

NE winds become lighter through the evening, and a few
locations may become light and variable. Winds then shift to
the E Friday morning and then SE late Friday morning into
Friday afternoon.


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

Timing of improving flight categories may be 1-2 hours earlier
than forecast. However, KTEB may remain MVFR until late
tonight.


OUTLOOK FOR 00Z SATURDAY THROUGH TUESDAY...

Friday night: MVFR with showers in the evening, lowering to IFR
late with showers.

Saturday: MVFR or lower with showers ending in the early
morning, becoming VFR. W-WNW winds G15-25 kt possible late.

Sunday: VFR. W winds G15-20 kt possible near the coast in the
afternoon/evening.

Monday and Tuesday: VFR.

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

&&

.MARINE...
SCA cond persist on most waters attm, with E-NE winds gusting to
25-30 kt (highest on the ocean) and ocean seas up to 9 ft.
Gusts over 25 kt should diminish on the non ocean waters before
sunset, but should take until closer to midnight on the ocean.
Ocean seas over 5 ft should however linger into daytime Fri and
possibly Fri night or early Sat morning.

High pressure should then keep conditions at sub-advisory levels
through at least Tue night. Conditions may build back to SCA
levels on Wed with the next low pressure and associated cold
front to approach.

&&

.HYDROLOGY...
No hydrologic impacts expected attm.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT Friday for ANZ350-353-355.
-- End Changed Discussion --

&&

$$

SYNOPSIS...BG/BR
NEAR TERM...BG/BR
SHORT TERM...BG
LONG TERM...BR
AVIATION...MET
MARINE...BG/BR
HYDROLOGY...BG/BR