Discussion on 2023-04-02

000
FXUS61 KOKX 021457
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1057 AM EDT Sun Apr 2 2023

.SYNOPSIS...
-- Changed Discussion --High pressure builds in through this evening and then moves
off the coast by early Monday morning. Low pressure passes
across eastern Canada on Monday, sending a warm front north of
the area. A trailing cold front approaches Monday night into
Tuesday, but weakens as it moves southward into Tuesday night. A
low pressure system moves into Southeast Canada and its
associated warm front moves north through the region Wednesday
into Wednesday night. An associated cold front moves across on
Thursday into Thursday night. High pressure returns thereafter
into next weekend.-- End Changed Discussion --

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --Forecast on track with only minor adjustments to account for
the latest observations and trends of temperature and dew point
into the afternoon.

Low pressure continues to depart east of New England this
morning with high pressure building in from the west. The
pressure gradient between these two systems is modest to start
to the day leading to NW wind gusts 25-35 mph. The gradient
weakens in the afternoon allowing gusts to diminish. Winds by
evening look to be around 10 mph with a few lingering gusts
15-20 mph.

Mostly sunny conditions are expected with below normal highs in
the upper 40s to lower 50s.

The high settles over the area tonight with nearly ideal
radiational cooling conditions. Winds should be mostly calm
with a dry air mass in place under mostly clear skies. There may
be a slight increase in mid and high clouds towards day break
Monday well NW of NYC, but do not think this will have any
impact on low temperatures. Lows will fall into the 20s inland
and LI Pine Barrens with lower to middle 30s elsewhere.-- End Changed Discussion --

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
Surface high pressure moves offshore Monday morning. The
flow aloft is mainly zonal through Monday. A shortwave and
associated low pressure track across eastern Canada which will
allow a warm front to lift north of the area. There will be some
middle and upper level moisture through the day, but think
skies will remain mostly sunny to partly cloudy. The most
noticeable change to the sensible weather will be with
temperatures warming into the upper 50s lower 60s across NE NJ,
NYC metro, and Lower Hudson Valley. Further east across Long
Island and southern Connecticut, temperatures will be in the
lower to middle 50s due to cooler onshore flow. S wind will also
increase to around 15 mph with gusts 25 to 30 mph in the
afternoon. Winds should decrease after sunset.

The aforementioned low pressure to our north will drag a cold
front towards the region Monday night. The guidance is hinting
at some subtle shortwaves in the predominately zonal flow aloft.
However, any precipitation looks to reside along the frontal
boundary to the north. The front does to try move closer to the
region late Monday night into Tuesday morning. Have included a
slight chance for the northern tier as the front may be close
enough to support a light shower. Any weak upper support quickly
diminishes with heights rising aloft late Tuesday morning and
Tuesday afternoon. The frontal zone appears to become washed out
and weaken nearby or over the area on Tuesday. In fact, the
model consensus has temperatures on Tuesday warmer than on
Monday with highs reaching the upper 60s to lower 70s along and
west of the Hudson River. Onshore flow further east will hold
temperatures down in the upper 50s to lower 60s.

The weak and ill defined surface boundary may settle just south
of Long Island Tuesday night as the surface flow becomes more
SE-E. Low stratus development appears likely, especially
overnight with both the NAM and GFS moisture profiles indicating
this potential. There may also be some light shower development
as weak warm advection occurs across the area. Have maintained
a slight chance PoP for the second half of the night. Lows
Tuesday night will be mild and in the 40s for much of the area
except low 50s in the NYC metro.

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Upper levels exhibit main upper level jet north of the region
Wednesday through Thursday night and then moving farther south
and closer to the local region Friday into start of next
weekend.

Mid levels convey ridging Wednesday with height falls Wednesday
night through early Friday. Quasi-zonal flow resumes Friday into
next weekend. Positive vorticity maxima in the mid levels move
across Wednesday into Wednesday night and move in from the north
for next Saturday.

At the surface, a warm front moves across Wednesday through
Wednesday night. Southeast surface winds transition to more
southerly and will become steady and gusty along the coastlines
for Wednesday night. Rain shower chances will increase
Wednesday with the front and some upper level support.

These rain shower chances will continue Wednesday night into
Thursday as a cold front approaches and moves across. Depending
on the timing of the cold front, there could be some low level
instability to work with, so a few embedded thunderstorms are
possible. Rain shower chances diminish Thursday night behind the
cold front.

High pressure builds in thereafter from the west, with its
subsidence keeping dry conditions Friday into the start of next
weekend.

Temperatures overall trend from being above normal Wednesday,
Wednesday night and Thursday, to closer to normal Thursday night
into the start of next weekend.

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --High pressure gradually builds in from the west through the TAF
period.

VFR conditions are expected. Gusty NW winds gradually diminish
through the day. Sustained wind speeds forecast near 15-20 kt
this morning, decreasing to closer to 10-15 kt in the afternoon.
Gusts forecast are near 30 kt this morning before dropping to
near 25 kt early afternoon and closer to 20 kt by late this
afternoon.

Winds decrease to near 5 kts with variable direction tonight.

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

End time of gusts could vary 1-2 hours from TAF.

...OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...

Monday: VFR. S-SW winds 15-20kt G20-25 kt, diminishing at night.

Tuesday: Mainly VFR.

Wednesday and Thursday: MVFR to IFR with showers. SW wind gusts
15-20 kt Thursday.

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

.MARINE...
-- Changed Discussion --Gusts have dropped below 35 kt so the gale warnings are replaced
with SCAs for the ocean zones through much of the afternoon and
into the early evening. SCA conditions may linger a bit longer
on the non-ocean waters as some gusts upwards of 25-30 kt remain
possible through 18Z. Winds should fall below SCA levels in the
afternoon, but seas will linger above 5 ft on the ocean. Seas
around 5 ft could also linger into this evening east of Moriches
Inlet.

There will then be a brief period of conditions below SCA
tonight into Monday morning before winds increase Monday
afternoon as a warm front lifts to the north. Winds decrease
Monday evening, but ocean seas may remain above 5 ft through the
night. Winds and seas look to be below SCA levels Tuesday and
Tuesday night.

Conditions on Wednesday will be mainly below SCA, just a part
of the ocean forecast to have SCA level conditions. For Wednesday
night, the ocean waters are forecast to get SCA level conditions
while non-ocean marine zones remain below SCA. These SCA level
conditions forecast to remain on the ocean Thursday into
Thursday night with most waters overall reaching SCA level
conditions for wind gusts.-- End Changed Discussion --

.HYDROLOGY...
No hydrologic concerns are expected through next week.

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 2 PM EDT this afternoon for ANZ331-
332-335-338-340-345.
Small Craft Advisory until 10 PM EDT this evening for ANZ350.
Small Craft Advisory until 8 PM EDT this evening for ANZ353.
Small Craft Advisory until 4 PM EDT this afternoon for ANZ355.-- End Changed Discussion --

SYNOPSIS...JM/DS
NEAR TERM...DS/MW
SHORT TERM...DS
LONG TERM...JM
AVIATION...JM/DW
MARINE...JM/DS/MW
HYDROLOGY...JM/DS