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-- Discussion containing changed information from previous version are highlighted. --
986
FXUS61 KOKX 300501
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
101 AM EDT Fri Sep 30 2016

.SYNOPSIS...
High pressure over southern Quebec will maintain a moist northeast
flow off the Atlantic Ocean into the weekend as low pressure
spins over the Ohio Valley. The unsettled weather may continue
into early next week before high pressure begins to exert its
influence from the north for mid week.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Some rain showers have moved onshore from the Atlantic. The
intensity remains light and coverage remains scattered. The HRRR
continues to have a reasonable handle on the situation, which
shows some of the heavier rain moving in mainly after 07Z for Long
Island. Otherwise, only minor changes made to the forecast.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
Followed the 29/12Z ECMWF deterministic run.

The uncertainty remains on the intensity of the rain. With the 15Z
SREF supporting rain through the period, categorical POP should
work out. Not a very nice day for most!

Winds will gust as high as 40 mph along the coast.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
Stagnant and unsettled weather pattern continues into this weekend
with stacked cutoff low pressure sitting over the Ohio valley...as
western Atlantic ridging holds firm. Models indicating that the
upper ridge gradually weakens and shifts south enough early next
week to allow the upper low to finally start moving northeast early
next week.

At the surface, stacked low pressure sits over the Ohio
Valley, with a stationary front running northeast from the Mid
Atlantic and southeast of Long Island through the weekend. A
series of weak waves running along this front will produce periods
of rain this weekend. Then as the stacked low finally begins to
lift northeast early next week, expect the the main moisture/lift
axis to also weaken and lift NE. Lingering scattered showers could
continue through early next week via cold pool instability
interacting with the maritime air mass.

Thereafter, potential for deep layered ridging developing for mid
week as the region lies under ridging of an omega blocked pattern.
The dry ridged pattern may continue into late week, but will have
to monitor the evolution of Hurricane Matthew. Please refer to
the National Hurricane Center forecasts for further information.

Temps will likely be several degrees below seasonable Sat and
possibly Sunday with cool air damming, clouds, and rainfall, then
should return to near seasonable for early next week.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
Terminal area will be in between high pressure to the northeast
and low pressure to the southwest into Friday afternoon.

MVFR ceilings overnight. Spotty rain and drizzle will arrive
shortly after midnight with patchy areas of moderate rain
developing by mid-late morning Friday. The exception is at KGON,
where light rain should hold off until early morning on Friday.

NE-E winds through the TAF period, gusting to 25-35kt at
city/coastal terminals and 15-25kt at inland terminals.

     NY Metro Enhanced Aviation Weather Support...

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

KJFK TAF Comments: Peak gusts could be 5kt or so higher than
those in TAFs.

KLGA TAF Comments: Peak gusts could be 5kt or so higher than
those in TAFs.

KEWR TAF Comments: Peak gusts could be 5kt or so higher than
those in TAFs.

KTEB TAF Comments: Peak gusts could be 5kt or so higher than
those in TAFs.

KHPN TAF Comments: Variable ceilings between VFR and MVFR possible
into this evening. Peak gusts could be 5kt or so higher than those
in TAFs.

KISP TAF Comments: Peak gusts could be 5kt or so higher than
those in TAFs.

.Outlook for 18Z Friday through Monday...
.Friday Afternoon-Saturday...IFR/MVFR in rain. NE winds g25-35 kt
Friday afternoon/evening.
.Saturday Night-Sunday Night...MVFR or lower possible with showers.
.Monday-Tuesday...VFR with isolated to scattered showers possible.

&&

.MARINE...
Winds increase slightly overnight into Friday Morning, thus have
issued a gale warning for all waters except NY Harbor.

SCA conditions expected Friday night into Saturday for the Ocean
and possibly all waters, but should begin to relent Sat night
into early Sunday as easterly flow weakens. Ocean seas should
follow suit as well.

Sub SCA conditions likely for early next week under a weak
pressure gradient.

&&

.HYDROLOGY...
There is a high degree of uncertainty on the amount of rainfall
through Friday. Moderate rainfall late tonight into Friday
morning for western sections and the NY Metro is possible, with
1/2 to 1 inch QPF possible.

Overall, totals should range in the 1-2 inch range through
Saturday night. The prolonged nature of the rain event should
preclude any hydrologic issues.

No significant rainfall for early to mid next week.

&&

.TIDES/COASTAL FLOODING...
With slight strengthening of ENE gales into the Friday morning
high tide cycle, would expect surge to at least match or even
slightly exceed that of tonight. With a slightly higher
astronomical high tide, this should result in widespread minor
coastal flooding for the above mentioned areas. NOTE: The flooding
could be exacerbated if high tide coincides with heavy rain Friday
morning, during the Fri morning rush.

Along western Long Island sound and the eastern bays of Long
Island, wind fields will be slightly weaker the next 24 hours,
and may be falling off by high tide times Fri late morning, but
can`t rule out localized minor coastal flooding or wave splashover
in the most vulnerable northeast and east facing spots during high
tide.

Although wind fields weaken for Fri Evening high tide, localized
minor flooding still may be a concern for the south shore of Long
Island.

Additionally, a persistent easterly sweep of 6 to 10 ft surf
through Friday will likely result in minor to moderate beach
erosion issues at the the ocean beachfront.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Coastal Flood Advisory from 6 AM to 11 AM EDT this morning for
     NYZ074-075-080-178-179.
NJ...Coastal Flood Advisory from 6 AM to 11 AM EDT this morning for
     NJZ006-106-108.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ338.
     Gale Warning until 6 PM EDT this evening for ANZ330-335-340-
     345-350-353-355.

&&

$$
SYNOPSIS...Goodman/Tongue
NEAR TERM...JP
SHORT TERM...Tongue
LONG TERM...NV
AVIATION...IRD
MARINE...Goodman/Tongue/NV
HYDROLOGY...Goodman/Tongue/NV
TIDES/COASTAL FLOODING...