398
FXUS61 KOKX 081954
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
354 PM EDT Wed May 8 2024

.SYNOPSIS...
A cold front stalls south of the area tonight before a low pressure
approaches the area from the west on Thursday. The low lingers over
the area through Friday night. A series of lows move through the
vicinity of the region this weekend. High pressure builds
offshore for early next week before another low potentially
moves in for the middle of next week.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
The area remains in a warm sector with a fair amount of
instability. Though forcing remains well to the north, some
thunderstorms developing in Western Massachusetts may approach
the extreme northern portions of the CWA later this afternoon. The
best chance to see any thunderstorms will be northern portions of
the area, though northeastern areas remain in a more stable airmass
than northwestern locations. If any storms develop, some may be
strong with damaging wind gusts and large hail.

Any storms come to an end this evening with a cold front moving
through. The cold front will dry out the airmass, though eastern
areas may remain moist enough to result in some patchy fog,
especially earlier in the night. Lows tonight will be generally in
the 50s, with the warmest spots in the west.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
Mid-level energy upstream will force a surface low pressure system
to move across the Ohio Valley and approach the area into Thursday.
Showers may approach the area during the morning but will become
gradually more likely into the afternoon. The latest model guidance
has trended much of the shower activity with this system to the
south, which may hold off much of the shower activity off until the
late afternoon or evening, especially for areas north and east.
Highs Thursday will be fairly seasonable with temperatures in the
middle 60s to low 70s.

As the center of the low pressure moves into the area Thursday
night, shower activity will increase substantially so that much of
Thursday night through Friday morning will have widespread showers,
some of which may be locally heavy with some embedded convective
elements possible, though thunder is not likely.

Though there is some uncertainty as to the exact placement of the
low on Friday, it looks to meander in the general area as an upper
level trough moves overhead, the surface low will spin over the
area on Friday resulting in additional shower activity during much
of the day. As such, temperatures will be below average with
highs only in the middle 50s. The shower activity should begin to
wind down from west to east overnight Friday and into early morning
Saturday.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
From analysis of large scale deterministic weather prediction models
of the GFS, ECMWF, and the Canadian models, the following features
were noted from the lower to upper levels.

The upper level jet is shown to remain south of the region this
weekend and then with more ridging next week, parts of the upper
level jet traverse the local area.

Mid level trough south of region Saturday morning, then shifts east
during the day with brief ridging as the local area will be in
between shortwaves.

Next shortwave moves in Saturday night with another moving south of
the region Sunday. The larger trough encompassing these shortwaves
and periodic positive vort maxima will be lingering across the
region through Sunday. This trough then moves east of the region
Sunday night.

Overall the larger scales convey a mid level ridging trend taking
place for early into middle of next week for the local area. For
Monday night into early Tuesday next week, a subtle small shortwave
embedded within the ridge is forecast to move across. By Wednesday,
especially late day into Wednesday night, next trough could be
potentially moving in from the west.

At the surface, low pressure moves south and eventually southeast of
the region Saturday. Weak pressure gradient follows across the local
region. This weak high pressure will be brief as low pressure
approaches Saturday night and moves near to south of the area early
Sunday. Low pressure passes southeast of the region Sunday into
Sunday night.

Offshore high pressure briefly builds in late Sunday night into
early Monday and then moves farther offshore as another wave of low
pressure approaches Monday afternoon into Monday night. This low
pressure will be weak and will traverse the local area late Monday
night into early Tuesday. Another low may approach the area next
Wednesday.

Chances of rain showers are forecast much of this weekend and for
Sunday when relatively the coldest air aloft moves across, put in a
slight chance of thunderstorms for the mid afternoon into early
evening hours.

Mainly dry conditions are forecast Sunday night through early
Tuesday. Then, next chance of rain showers is forecast Tuesday
afternoon into the midweek timeframe.

Temperatures for the weekend exhibit less of a diurnal trend, and
generally expected to be below normal for daytime hours and then
near to above normal for next week.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
A cold front approaches from the NW late this afternoon and passes
across the area this evening.

This will mainly be a VFR forecast with the exception of KGON that
will contend with occasional IFR ceilings through early this
evening.

Isolated showers and maybe a thunderstorm will be possible late this
afternoon into the early evening, with the best chance at KGON.
Confidence is too low to mention elsewhere.

Winds will continue to veer around to the WSW for the NYC and Lower
Hudson terminals, but will be slower to do so for the eastern
terminals due to a maritime influence. For those locations that
become WSW, winds will increase to around 15 kt with G20-25t. A few
30 kt gusts are possible. Gusts diminish this evening with winds
becoming WNW at 10 kt or less following a cold frontal passage.
Winds will continue to veer around to the NE Thursday morning. An
afternoon seabreeze is possible, but confidence is low.

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

Gusts may linger for 1-3 hours after 00Z.

OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY...

Thursday Afternoon/Night: Mainly VFR with a chance of showers in the
afternoon, then MVFR or lower developing at night with a continued
chance of showers.

Friday: MVFR or lower with showers likely.

Saturday and Sunday: Chance of MVFR or lower in showers.

Monday: Mainly VFR. Isolated showers possible at KSWF.

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

&&

.MARINE...
Winds and seas are expected to remain below SCA conditions
through Thursday. Seas and winds may approach SCA criteria with
winds near 20 kt and seas approaching 5 feet. Any marginal SCA
conditions diminish once again into Friday and stay below SCA
through at least Friday night.

For the long term period of Saturday through Monday night, SCA
conditions are probable on the ocean, due to mainly seas, for much
of the timeframe. Wind gusts stay mainly below SCA thresholds. Sub-
SCA conditions are forecast for non-ocean zones.

&&

.HYDROLOGY...
Upwards of 0.5" to 1" of rainfall is possible for western
portions of the area Thursday night through Friday but are not
expected to result in any hydrologic impacts. No hydrologic
impacts are expected during the long- term forecast period.

&&

.TIDES/COASTAL FLOODING...
Astronomical tides run high the next few days with the new moon from
last night.

Minor flood benchmarks are likely to be exceeded during the evening
high tide cycles tonight through Friday night for southern
Nassau, southern Queens, and Fairfield and Westchester counties
with inundation up to a foot. Coastal flood statements will be
in place for tonight`s high tide for Newark Bay in Hudson county
and southern Queens with water levels perhaps just touching
minor benchmarks. Localized moderate flooding is possible during
Fri evening`s high tides in the most vulnerable spots of
southern Nassau, with advisories and statements likely in
similar locations tonight, and perhaps including SW Suffolk and
portions of the north shore of Long Island in subsequent
evening high tide cycles through Friday. Statements may also be
needed for Thursday and Friday evening for portions of coastal
NE NJ and Staten Island.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Coastal Flood Advisory from 11 PM this evening to 2 AM EDT
     Thursday for CTZ009.
NY...Coastal Flood Advisory from 11 PM this evening to 2 AM EDT
     Thursday for NYZ071.
     Coastal Flood Advisory from 8 PM to 11 PM EDT this evening for
     NYZ179.
NJ...None.
MARINE...None.

&&

$$

SYNOPSIS...JM/MW
NEAR TERM...MW
SHORT TERM...MW
LONG TERM...JM
AVIATION...DW
MARINE...JM/MW
HYDROLOGY...JM/MW
TIDES/COASTAL FLOODING...