Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 292211
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
611 PM EDT Thu Sep 29 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 FRIDAY MORNING/...
The problem in the near term is the rain pushing north out of
south and central Jersey. Believe the 12Z ECMWF has a good handle
on this. But confidence is low since latest RAP and HRRR keep us
basically dry overnight. The rain is in response to the strong
over-running of the coastal front to the south.

Have followed the deterministic ECMWF for POPs and QPF - which
again may be way too high, but current RADAR trends are hard to
ignore.

Also, the cloud cover forecast over CT is a problem. Would suspect that
this fills in quickly this evening, but is may be later rather
than sooner.

NOTE: We have ended our Surf Zone Forecasts for the Long Island
Beaches. With seas up to 6 ft in the surf zone and strong long
shore currents - even experienced surfers should exercise extreme
caution.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Following the ECMWF 12Z deterministic run for tomorrow.

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

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

&&

.LONG TERM /SATURDAY 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 its warm front remaining stationary running northeast
from the Mid Atlantic and southeast of Long Island through the
weekend. A series of weak waves running along this front will result
in 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 weaken and lift NE of the region. Lingering
scattered shower activity possibly continues through early next week
with cold pool instability interacting with the maritime airmass.

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. Refer to the National
Hurricane center forecasts for the latest information.

Temps likely several degrees below seasonable Sat and possibly Sun
with cold air damming...clouds and rainfall. Near seasonable temps
likely for early next week.

&&

.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
Terminal area will be in between high pressure to the northeast and
low pressure to the southwest into Friday afternoon.

MVFR ceilings return overnight to all but KSWF and KGON where it
should develop Friday morning. Light rain looks to start towards
sunrise Friday, with moderate rain developing by mid-late Friday.
The exception is at KGON, where light rain should hold off until
around midday on Friday.

NE-E winds through the TAF period, gusting to 25-35kt at
city/coastal terminals and 15-25kt at inland terminals. Gusts could
be intermittent at times into this evening.

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

KEWR TAF Comments: A chance of VFR this evening. Peak gusts could
be 5kt or so higher than those in TAFs.

KTEB TAF Comments: Variable ceilings between VFR and MVFR possible
into this evening. 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...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 weak pressure
gradient.

&&

.HYDROLOGY...
There is a high degree of uncertainty on the amount of rainfall
through Friday. Moderate rainfall overnight into Friday morning
for western sections and the NY Metro is possible with up to an
inch of QPF possible.

Overall, totals should range in the 1-2" range through Saturday
night, though this may be on the high end depending on how things
evolve overnight into Friday Morning.

Regardless, the prolonged nature of the rain event should
preclude any hydrologic issues.

No significant rainfall for early to mid next week.

&&

.TIDES/COASTAL FLOODING...
A persistent moderate northeast flow through Friday will keep persistent
elevated water levels.

Water levels across the Atlantic Ocean facing south shore bays in
Nassau will reach minor tidal flooding benchmarks again tonight -
a few inches higher than this morning.

Latest data does not support expansion of the minor flooding on
Friday - with just the bays of southern Nassau reaching minor
benchmarks.

An advisory has been issued for this evening`s and tomorrow`s high
tide. Another advisory will likely be needed for Friday evening`s
high tide.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Coastal Flood Advisory until 10 PM EDT this evening for NYZ179.
     Coastal Flood Advisory from 6 AM to 9 AM EDT Friday for NYZ179.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT Friday for ANZ338.
     Gale Warning until 6 PM EDT Friday for ANZ330-335-340-345-350-
     353-355.

&&

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


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