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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 121147
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
747 AM EDT Mon Apr 12 2021

.SYNOPSIS...
Weak waves of low pressure along a stationary boundary will pass
nearby and settle just to the south through tonight. Weak high
pressure builds in towards Tuesday and Wednesday, with another
low pressure possibly impacting the area by Thursday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Forecast on track. This update accounts for the latest
observations and trends through the morning. Widespread showers
overnight have become a little more scattered. Showers are now
mainly over the eastern half of the CWA but additional showers
are expected to develop in western portions into the morning.

As a nearly stationary warm front remains just south of the area, weak
low-level WAA is continuing to force showers over the area. This
unsettled weather will likely continue through much of the day with
scattered showers persisting under primarily easterly flow. Mid-level
vorticity over the southern Great Lakes region will push to the south
of our area along the stationary front allowing for the
precipitation to follow it late this afternoon. This means that
areas to the NE may not see as many showers by the afternoon.
Areas toward the west (i.e., Lower Hudson Valley, NE NJ, and
the NYC metro) will likely see showers through much of the day
and into the evening since these areas will be closer to the
passing disturbance.

Overall, the day will be showery under overcast skies. Temperatures
won`t rise too much with highs only in the low 50s. Easterly flow will
persist through the day with gusts upwards of 20 - 25 mph, especially
closer to the coast.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
As the disturbance continues to move south of the area into tonight,
showers mainly over the western portion of the area will begin to push
out to the south. By sunrise on Tuesday, the showers are
expected to completely exit the area. Lows tonight will be in
the upper 30s and low 40s.

By Tuesday, some mid-level ridging takes place over the region
allowing for a brief period of weak high pressure to build into
the area. This should allow for conditions to remain fairly dry
much of the day on Tuesday with skies being mostly sunny to
partly cloudy into the afternoon. Highs will be in the upper 50s
and low 60s.

Skies will remain partly cloudy for the beginning of Tuesday night but
clouds increase in coverage overnight as another mid-level disturbance
approaches from the NW. Most of the night however should remain dry.
Lows will be in the low to middle 40s.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
There have been some notable changes/trends in the modeling today.
The next upr trof, currently over ern MT, slowly approaches the
area for the end of the week. With a series of 3 h5 lows set up
along roughly the same latitude, slow progress seems realistic.
The h5 setup allows for the development of low pres invof the
cwa. This sfc low reflection would also be slow moving, and the
latest data indicates impacts Thu and Fri. This notion of a slow
moving low is not new, as it was in the modeling a few days
ago. With the 12Z GFS supporting the 00Z ECMWF, confidence is
growing in the scenario. Mainly a rain event, although if
everything comes together perfectly, some wet snow will be
possible at times across the interior. The NBM was used for
pops, but temps were dropped a few degrees blw the NBM. Likely
dry on Sat if the timing of the systems holds, then perhaps some
shwrs possible on Sun ahead of the next upr low, or remnants
thereof.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
A warm front across southern Pennsylvania into the Delmarva
remains south and west of the terminals into Monday. High
pressure builds in tonight.

VFR to MVFR conditions this morning, becoming MVFR to IFR late
in the day and tonight. Conditions improve late tonight.

Easterly winds 5-15 kt. There may be occasional gusts to 20 kt.


The afternoon KJFK, KLGA, and KEWR haze potential forecast is
RED, which implies slant range visibility less than 4SM outside
of cloud.

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

Amendments likely due to uncertainty in timing of flight
category changes.

.OUTLOOK FOR 06Z TUESDAY THROUGH FRIDAY....
.Monday night...IFR in the evening with showers, improving to
VFR by Tues AM push.
.Tuesday...VFR.
.Wednesday...VFR, a chance of MVFR late in the day with showers.
.Thursday-Friday...MVFR to IFR with a chance of rain.

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

&&

.MARINE...
SCA conditions will continue on all waters through early afternoon.
Thereafter, winds will diminish to below SCA criteria.

Waves on the ocean waters are expected to be 5 to 7 ft through this
morning, then slowly diminish this afternoon, but should remain
above 5 ft through tonight. Therefore, the SCA on the ocean waters
was extended through 8 am Tuesday, and may need to be extended
through Tuesday morning as 5 ft seas look to continue until then.

Thereafter, winds and waves will remain below SCA criteria through
Tuesday night and Wednesday.

Low pressure may impact the waters towards the end of the week, with
at least SCA winds and seas.

&&

.HYDROLOGY...
Generally speaking an additional 0.25"-0.75" of rainfall is
possible through tonight. No hydrologic impacts are expected
Tue-Sat.

&&

.TIDES/COASTAL FLOODING...
Tides will be running high astronomically, through tonight,
with a new moon phase. With an increased and persistent onshore
flow, there is the chance that a few locations for the Western
Sound Shore in CT and the more western south shore bays will
approach, or touch, their minor coastal flood benchmarks with
the high tide cycles today and tonight.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 2 PM EDT this afternoon for ANZ331-
     335-338.
     Small Craft Advisory until 6 PM EDT this evening for ANZ332-
     340-345.
     Small Craft Advisory until 8 AM EDT Tuesday for ANZ350-353-355.

&&

$$
SYNOPSIS...JMC/MW
NEAR TERM...MW
SHORT TERM...MW
LONG TERM...JMC
AVIATION...JP
MARINE...JMC/JP
HYDROLOGY...MW
TIDES/COASTAL FLOODING...