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000
FXUS61 KOKX 171822
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
Issued by National Weather Service Mount Holly NJ
222 PM EDT Wed Apr 17 2024

.SYNOPSIS...
A slow moving warm front approaches from the southwest today
and moves through the area into Thursday. High pressure briefly
builds in for Thursday night into Friday before a cold front
passes through Friday night into Saturday morning. High pressure
then follows from Saturday afternoon through early next week. A
weak frontal system will impact the region mid week.

&&

.NEAR TERM /THROUGH TONIGHT/...
A high amplitude upper level ridge over southeastern Canada and
western New England will continue to shift east today and and
will start to deamplify over the Mid Atlantic this evening.
As this occurs, a weakening stacked low over the Great Lakes
region will eventually lift a surface warm front associated
with this low will approach from the southwest today.

The warm front will lead to isentropic lift in association with
overrunning moisture thus bringing rain showers into the region
during the late afternoon and evening. Instability will continue
to be the challenge with the overall thunder potential but given
that there has been some lightning upstream the forecast now
includes a slight chance of some embedded thunderstorms.
Confidence is low (15%) on the likelihood of widespread mention
of thunder especially with a modest low level inversion keeping
much of the area stable. The 12z suite of CAMs still indicated
the potential for some short lived embedded heavier showers
moving through southwestern portions of the forecast area
overnight tonight within the New York City metro area.

During the overnight expect the shower coverage to increase
although decrease in intensity. As the WAA lift decreases,
showers will transition from potentially heavy at times to more
of a steady light rain.

Temperatures are expected to be near normal for this time of year.



&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
Shower coverage looks to lower Thursday as isentropic lift
weakens over the area and high pressure building in from the
northeast brings in a cooler and drier air mass in the lower
levels.

The high building in with the weak low to our south will mean a
strengthening easterly flow develops across the area that
starts to increase late tonight. It does not look to be overly
windy, with sustained winds of 15 to 20 mph and gusts to 25 mph
by Thursday morning. Winds start to decrease Thursday afternoon
as the high continues to nose into the region, with the weak low
well out to sea by this point.

The easterly flow will also mean cooler than normal temperatures for
Thursday, with highs only in the upper 40s to lower 50s.

Mainly dry conditions from Thursday night (except perhaps some
lingering showers for eastern areas) through Friday morning with
high pressure over the region. The chances for showers increase
Friday afternoon and Friday night as the associated cold front
approaches and begins to move through late Friday night.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Little change in the long term and stuck fairly close to the
previous forecast/NBM.

A cold front approaches and passes through Friday night into
Saturday morning. Moisture will deepen along with a chance of
showers with its passage. High pressure then builds in behind the
front with dry weather for Saturday afternoon. The high will
continue to build into the region through the rest of the weekend
and remain in control of the weather through Monday. High
temperatures near normal on Saturday, but cooling off slightly for
Sunday. Temperatures rebound a few degrees on Monday.

A 500mb trough then shifts through the Great Lakes on Tuesday with
an associated weak surface low and cold front. It appears that we
should by dry through the day, but cannot rule out a shower for
western zones by the end of the day. Rain chances increase Tuesday
night into Wednesday. Temperatures remain in the lower and middle
60s.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
High pressure over the terminals weakens today as a warm front
slowly approaches from the southwest.

VFR through most of the day. Showers/rain become likely around 22z,
however there is a chance that some light precip starts at early as
20z. Most of the precip though 23-00z should remain VFR,
however can not rule out a brief period of MVFR conditions with
the rain. MVFR conditions become more likely towards 00z, then
dropping to IFR around 02-04z as the light rain become more
steady.

Winds should be generally easeterly thorugh the rest of the
afternooon between 08-12kt with occasional gusts mixing to the
surface up to 20kt. Wind direction will generally be between
080-120 for much of the TAF period.

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

Timing of the onset of light rain and MVFR conditions late
this afternoon may be off by 1-2 hrs.


OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...

Thu and Thu night: IFR conditions and possibly LIFR at times
Thursday. Showers end with slowly improving conditions Thursday
night. Winds will be from the east around 15kt with gusts
20-25kt, highest along the coast.

Fri: VFR early, then MVFR late day and at night with a chance of
showers.

Sat: MVFR with showers ending in the morning, becoming VFR.

Sun: VFR.

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

&&

.MARINE...
Winds and seas remain below SCA criteria throught this afternoon
and early evening. However, easterly winds will increase
tonight as strengthening high pressure builds in, and by late
tonight will likely reach 25 kt on the ocean waters and the
entrance to the harbor. A few hours later, all waters will see
SCA wind gusts. A SCA is in effect for all waters from late
tonight through the day on Thursday.

Winds gusts diminish Thursday night as the high continues to
build in over the area. Non ocean waters will likely drop below
25 kt early Thursday night. The ocean waters will likely have
SCA gusts hang on for the first few hours of Thursday night
before they also come down below 25 kt.

Seas build to 4 to 7 ft on the ocean by Thursday morning into
the afternoon, diminishing thereafter. However, they remain
above or right around 5 ft Thursday night, so an extension to
the SCA over the ocean may be needed for Thursday night and
perhaps into Friday with a persistent, though slowly weakening
easterly flow. Waves finally drop below 5 ft on the ocean by
Friday night.

High pressure building over the area waters Saturday through the
first part of next week should keep conditions sub-advisory waters
through at least Tuesday night. Conditions may build back to SCA
levels for Wednesday with the next low pressure and associated cold
front to approach.

&&

.HYDROLOGY...
There is the potential for 0.25" to 0.75" of rainfall from
late this afternoon through Thursday afternoon. Although a
brief heavy showers is possible, no hydrologic impacts are
expected with this event and thereafter through the first half
of next week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 6 AM to 6 PM EDT Thursday for ANZ331-
     332-335-340-345.
     Small Craft Advisory from 2 AM to 6 PM EDT Thursday for ANZ338-
     350-353-355.

&&

$$

SYNOPSIS...OKX
NEAR TERM...99
SHORT TERM...OKX
LONG TERM...OKX
AVIATION...99/OKX
MARINE...99/OKX
HYDROLOGY...OKX