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000
FXUS61 KOKX 170607
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
207 AM EDT Wed Apr 17 2024

.SYNOPSIS...
High pressure builds in overnight. A slow moving warm front then
approaches from the southwest tomorrow and moves through the area
into Thursday. High pressure briefly builds in for Friday before
a cold front passes through Friday night into Saturday morning.
High pressure then follows from Saturday afternoon through
early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
The forecast is on track with minor changes needed. Temperatures
in outlying areas were colder than forecast, so adjusted
temperatures down in those areas. High clouds will stream in
from the west, and this looks like it will allow temperatures to
remain steady or rise later tonight.

Upper level ridging upstream is allowing for a surface high pressure
to build into the area overnight. This will result in fairly
clear skies with a light northerly flow. Only some cirrus clouds
are spilling down the ridge out of the NW. Any location that is
able to relax the wind a bit more, mainly outlying and inland
areas, may cool more than forecast with skies mainly clear
during much of the night. Cooler spots may drop into the upper
30s, but much of the area should remain in the 40s with NYC near
50.

&&

.SHORT TERM /THURSDAY/...
The upper level ridge shifts overhead as the surface high
pressure shifts to the east tomorrow. A mid-level shortwave
moving over the Great Lakes allows a weakening surface low to
move into Southern Canada. The associated warm front approaches
the area from the southwest into the afternoon and evening and
will allow rain chances to increase due to deep-layer warm air
advection. While rain should be fairly widespread, especially
into the evening and overnight, much of the area should see
anywhere from 0.25" to 0.75" of rainfall, most of which should
fall tomorrow night and into early Thursday. While the rainfall
doesn`t appear to be convective in nature, some isolated
convective elements will be possible along with the low chance
of thunder, especially for southwestern areas into the evening
and overnight.

The rainfall will lighten up and showers should become more
widely scattered as the main area of forcing shifts south into
Thursday. Moisture will still be present and despite a lack of widespread
forcing, shower activity may continue into the day on Thursday,
progressively becoming lighter and less likely through the day.

An easterly flow and chances of rain will drop highs tomorrow about
5 to 10 degrees cooler than today, and this trend continues
into Thursday. East winds ramp up tomorrow night into Thursday
as the pressure gradient strengthens between the departing high
and the warm front. Gusts potential is 20 to 30 mph, highest
along the coast. A frontal wave developing along the warm front
pushes off the Mid Atlantic coast on Thursday.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
An inverted trough extending north from low pressure to our south
will linger near the forecast area Thursday night through Friday.
Moisture will be shallow during this time, but there could be just
enough isentropic lift in the vicinity of the trough for some
drizzle. Cloudy otherwise, with high temperatures in the middle to
upper 50s on Friday.

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 and Monday.

A 500mb trough then shifts through the Great Lakes on Tuesday with
an associated weak surface low. 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.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
High pressure over the terminals weakens on Wednesday as a warm
front slowly approaches from the southwest.

VFR through most of Wednesday. 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 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 will be light and variable overnight. Winds increase
around daybreak with speeds between 08-12kt taking in more of an
easterly component. 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 wind changes overnight into Wednesday morning is
uncertain and depends on the how quickly high pressure weakens
and the speed of the warm front approach. Timing of the onset of
light rain and MVFR conditions late Wednesday may be off by 1-2
hrs.

OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...

Wed night through Thu night: IFR conditions and possibly LIFR at
times with showers Wednesday night through Thursday. Showers end
with slowly improving conditions Thursday night. Winds Thursday
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...
Wind and seas are forecast to remain below SCA as high pressure
builds in from the NW through overnight. A warm front approaches
on Wednesday with a tightening pressure gradient between the
front and departing high. There is the potential for SCA
conditions in an easterly flow late Wednesday night into
Thursday. Gusts of 25 to 30 kt will be possible with seas on the
ocean of 4 to 7 ft.

Winds diminish Thursday night into Friday, however a lingering swell
with onshore flow may keep ocean seas above 5 ft through at least
Friday morning. Otherwise, sub-advisory conditions on all
waters Friday afternoon through Sunday.

&&

.HYDROLOGY...
There is the potential for 0.25" to 0.75" of rainfall from
late Wednesday afternoon through Thursday afternoon. No
hydrologic impacts are expected with this event.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$

SYNOPSIS...JC/MW
NEAR TERM...JP/MW
SHORT TERM...MW
LONG TERM...JC
AVIATION...BC
MARINE...JC/MW
HYDROLOGY...JC/MW