016
FXUS61 KOKX 150227
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1027 PM EDT Tue May 14 2024

.SYNOPSIS...
Low pressure develops along a frontal boundary tonight and
moves towards the region on Wednesday. The low will move south
of long Island Wednesday evening and becomes nearly stationary
Wednesday night into Thursday morning before starting to move
away from the region late Thursday. Weak high pressure on Friday
will be followed by another frontal system and potential wave
of low pressure over the weekend. High pressure then builds in
for early next week.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
With light rain showers across portions of western Suffolk
county have increased probabilities farther east into late
tonight, as pockets of light rain continue across western LI,
NYC, NE NJ, and the Lower Hudson Valley. This area moves little
the first half of the night, trying to overcome dry low-levels.
The column is expected to moisten up overnight as an upper level
shortwave approaches and surface low pressure develops south of
the region. This low will slowly move towards the region
overnight. Will not mention any thunderstorms in the forecast
with the environment becoming more stable. The best chances for
showers overnight will remain across NYC and points west.
Overnight lows fall into the 50s.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
As low pressure continues to approaches from the south on
Wednesday, and eventually moves south of Long Island Wednesday
evening. The low will become nearly stationary or meander south
of the area into early Thursday morning, before finally moving
away from the region Thursday afternoon.

This is a change from the 00z guidance. The 00z NAM forecast
had showed the area mainly dry with low pressure passing further
south. The new 12z NAN has the low further north, resulting in
a rather wet period Wednesday into early Thursday. Forecast will
now reflect this trend, with likely POPs overspreading the area
on Wednesday and remains likely into early Thursday, before
slowly tapering off Thursday as the low slowly starts to move
further away from the region.

As the low approaches on Wednesday, expect most of the shower
activity to becomes more of a stratiform rain and continue into
Thursday. The rain appears to be mainly light but over a 24-36
hour period, rainfall amounts are expected to range between a
quarter and three quarters of an inch.

With cloud cover and rain expected expect less of a diurnal
temperature range with a more maritime airmass developing. Highs
Wednesday and Thursday mostly in the 60s while lows each night
are mostly in the 50s.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Another system very much like the one preceding it midweek will
potentially impact the area over the weekend. However, there is
quite a bit of spread in the globals with the southern branch
closed low as it moves near the Mid Atlantic coast at the end of
the weekend and offshore early next week. This seems partly due
to the interaction of a northern stream shortwave trough
lifting across the Great Lakes Friday and into eastern Canada
over the weekend. While the two streams remain separate, their
influence on one another will determine the placement of the
upper low. The 12Z ECMWF takes the upper low and shears it off
with the bulk of the energy moving into the Southeast U.S. The
GFS and Canadian have the low track much farther north with the
potential for the area to get into the better forcing just north
of its track. The ECMWF is a mainly dry forecast with surface
ridging remaining in place. Thus, the NBM was followed with some
adjustments based on the aforementioned operational run and the
latest consensus forecast. This gives the area increasing
chances of rain late Friday night into Saturday night before
lowering on Sunday. On the front and back ends of the forecast,
Friday and Monday, expect high pressure. Thus, there is quite a
bit of uncertainty in the forecast over the weekend. There is
good reason to expect changes in the forecast with subsequent
issuances.

Highs during the period will be closer to normal Friday and Monday,
but several degrees below over the weekend due to the chances of
rain. This could very well change due to the differences previously
mentioned in the low track. Lows will be on the mild side due to a
prolonged period of cloud cover forecast.

&&

.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
A low develops along a warm front off the North Carolina tonight
and then slowly deepens and moves northward, to near the
Delmarva by Wednesday evening.

Low confidence forecast with timing of lowering conditions
through the overnight. Also uncertain of ceiling heights.

Generally VFR with lowering conditions to MVFR overnight and
IFR late overnight into Wednesday morning. Scattered showers
continue mainly at the NYC metro terminals and north and west.
Showers become more likely overnight and continue through
Wednesday. KGON will remain VFR into Wednesday morning then
lower to MVFR with rain developing around midday.

Light southerly flow becomes light and variable before becoming
SE Wednesday morning and increasing to around 10 kt. Winds
continue to back to the E and then NE through the day, and
increasing to around 15kt, mainly along the coast.


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

Amendments possible as cigs lower tonight and Wednesday. Low
confidence in timing of IFR cigs late tonight into Wednesday.


OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY...

Wednesday night: IFR to LIFR in rain, fog, and stratus.


Thursday: MVFR, possibly improving to VFR late in the day. A
chance of showers. NE winds G20kt.

Friday: VFR. Slight chance of a shower late.

Saturday and Sunday: IFR/MVFR possible. Chance of showers. SE
winds G15-20kt.


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

&&

.MARINE...
Conditions are forecast to remain below SCA thresholds on all
waters through Wednesday. For Wednesday night and Thursday, SCA
conditions become likely on the ocean waters as well as NY
Harbor and the South Shore Bays. For the ocean, expect winds and
seas to build to SCA levels. For the Harbor and south Shore
bays, expecting gusts to at least reach 2 5 kt for part of this
period. Lesser confidence of reaching SCA levels on the
remainder of the other waters, so no headlines expected there at
this time.

A weakening easterly flow Thursday night into Friday will
result in diminishing winds and seas. There is the potential for
marginal SCA gusts near 25kt on the ocean Thursday night. SCA
seas on the ocean are likely to linger into Saturday and
possibly longer depending on the track of low pressure over the
weekend. The non-ocean waters are forecast to remain below SCA
through the period.

&&

.HYDROLOGY...
No hydrologic problems are expected through the beginning of
next week.

Rainfall in the Wednesday-Thursday time frame will generally remain
fairly light with amounts on average between 0.25 and 0.75 inches.
Can not rule out a few isolated higher amounts with Long Island
being the best spot to see those higher values.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 6 PM Wednesday to 6 PM EDT Thursday
     for ANZ338-345-350-353-355.

&&

$$

SYNOPSIS...BC/DW
NEAR TERM...BC/MET/DW
SHORT TERM...BC
LONG TERM...DW
AVIATION...MET
MARINE...BC/MET/DW
HYDROLOGY...BC/DW