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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 232105
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
505 PM EDT Fri Jun 23 2017

.SYNOPSIS...
A cold front will slowly approach tonight, eventually moving
across Saturday morning into Saturday afternoon. A secondary
cold front moves across Saturday night. High pressure builds to
our southwest Sunday into Monday. A weak cold front will move
through our area later Monday. High pressure builds towards the
Mid Atlantic coast Tuesday and Wednesday, before moving offshore
Thursday. Unsettled weather return for the end of the week.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
-- Changed Discussion --
The main forecast concern tonight into early Saturday will be the
heavy rain associated with any showers and thunderstorms ahead of an
approaching cold front. There is more instability this evening
with less overnight. More details on this in the hydrology
section but there will essentially be a low chance of flooding
because of the heavy rain potential. This is from the remnant low
of Cindy that will be traveling along the cold front and this
moves in by early Saturday. Elevated instability as diagnosed from
Showalter indices only slightly negative so have lowered coverage
of thunderstorms overnight to isolated in forecast overnight.
Shear further increases with low level jet tonight as SW winds
increase to 45-55 kt between 3 and 4 kft, so any thunderstorm that
develops could be strong with gusty winds with a marginal threat
that thunderstorms could be severe.

Lows tonight were a blend of NAM12/GMOS and adjusted slightly
higher. Overall, temperatures will not drop much from this
evening through the night. Boundary layer moistens overnight
with patchy fog developing, especially in areas that are outside
the rain showers.

The moderate risk of rip current development continues through
this afternoon, due to building southerly winds waves and a 2
ft long period SE swell.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
-- Changed Discussion --
Starting out Saturday morning, the remnant low of Cindy with
the showers and thunderstorms will be near to just southwest of
the region. Heavy rain threat remains early in the morning with
patchy fog early especially in areas outside of rain showers. It
moves south of Long Island Saturday afternoon as the cold front
moves across. The showers and thunderstorms move offshore in
the afternoon as winds become more westerly. Depending on how
fast clouds decrease, the surface temperatures could warm up
quickly. Expecting an above normal day regarding temperatures
with boundary layer mixing giving highs mid to upper 80s most
places with some lower 90s in Northeast NJ using GMOS with
slight adjustments.

For Saturday night, a secondary cold front moves across which
will result in winds becoming more northerly late Saturday night
after its passage. Dry conditions, light winds and continued
mostly clear conditions will result in radiational cooling. A
vast range of lows will be seen in the region from upper 50s in
rural inland sections to lower 70s in parts of NYC from the MET
guidance.

A moderate risk of rip currents is forecast for Saturday.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Dry conditions expected on Sunday as a ridge of high pressure builds
towards the Mid Atlantic coast. Expect high temperatures to be in
the low to mid 80s on Sunday. A weak surface cold front will affect
the local area Monday afternoon into Tuesday. The system will not
have a great deal of moisture associated with it, but cooler
temperatures aloft may  spark off a shower or t-storm late Monday
into early Tuesday. High temperatures on Monday and Tuesday are
expected to be in the mid to upper 70s to lower 80s.

High pressure continues to build towards the area on Wednesday and
slowly moves offshore on Friday. A few showers are possible Friday
afternoon. Temperatures will start out in the upper 70s to near 80
on Wednesday then slowly increase to mid to upper 80s by Friday.

&&

.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
Low pressure tracks through eastern Canada this afternoon into
Saturday morning with an associated cold front approaching this
evening and moving through the terminals 12Z to 16Z Saturday.

Winds will be generally from the southwest 220 true, with gusts to
around 20 kt. Sea breeze influence will keep the winds more
southerly along the coastal areas this afternoon. With the passage
of the cold front winds shift to west to northwest, to the left of
310 true, and become gusty Saturday morning.

Generally VFR with occasional MVFR ceilings this afternoon.
Restrictions in fog and showers develops after 06Z, isolated to
scattered thunder is possible late this afternoon and this evening.
Another round of showers develops late tonight with the chance of
heavy rain and IFR visibilities.


     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: Occasional MVFR conditions possible through
23Z. Amendments possible late this afternoon and this evening
for developing thunderstorms.

KLGA TAF Comments: Gusts may be occasional this evening.
OccasionalMVFR conditions possible through 23Z. Amendments
possible late this afternoon and this evening for developing
thunderstorms.

KEWR TAF Comments: Gusts may be occasional this evening.
OccasionalMVFR conditions possible through 23Z. Amendments
possible late this afternoon and this evening for developing
thunderstorms.

KTEB TAF Comments: Gusts may be occasional this evening.
OccasionalMVFR conditions possible through 23Z. Amendments
possible late this afternoon and this evening for developing
thunderstorms.

KHPN TAF Comments: Amendments possible late this afternoon and this
evening for developing thunderstorms.

KISP TAF Comments: Amendments possible late this afternoon and this
evening for developing thunderstorms. The chance of thunder is less
likely east of the NYC terminals.


.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
.Saturday...VFR. WNW winds gusting around 20 kt.
.Saturday night-Sunday Night...VFR.
.Monday-Tuesday...VFR. A chance of shra/tsra Monday afternoon into
Tuesday.
.Wednesday...VFR.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
Conditions on the waters are becoming more rough. Sub SCA winds
on non-ocean waters are expected through Saturday night. Ocean
stays in SCA through much of Saturday night. Less SCA winds
Saturday night with an overall weak pressure gradient with
residual higher seas.

Conditions across the area waters are expected to remain below
small craft advisory levels Sunday through the middle of the
week.
-- End Changed Discussion --

&&

.HYDROLOGY...
-- Changed Discussion --
The potential for minor urban and poor drainage flooding with
localized possible flash flooding will remain with the showers
and thunderstorms forecast through early Saturday. Total rain
expected is 0.5 to 1 inch with locally higher amounts. The
precipitable waters increase to near 2.3 to 2.4 inches early
Saturday with tropical moisture from the remnants of Cindy
getting entrained along the front.

There is a threat for flash flooding late tonight through
Saturday morning from a likely complex of showers and
thunderstorm associated with a frontal wave (remnants of Cindy)
moving through the areas. Uncertainty exists on the
exact track of this wave...which could be from the Northern Mid-
Atlantic to Southern New England.

There are no hydrologic impacts expected Sunday and through the
end of the week.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
Astronomical tides are running very high, especially during the
evening high tide cycles tonight and Saturday.

Less than 1 ft of surge is needed during these evening high tide
cycles for minor flooding, and in some cases less then 1/2 ft.
The expected S/SW flow is not favorable for surge, but a
background anomaly will likely be enough for minor coastal
flooding of the most vulnerable coastal locales along the south
shore bays of Western Long Island, along Jamaica Bay, and along
western Long Island Sound during this time.

&&

.EQUIPMENT...
KOKX weather radar is scheduled for maintenance starting today June
23rd for a period of 3 days.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 2 AM EDT Sunday for ANZ355.
     Small Craft Advisory until 6 AM EDT Sunday for ANZ350-353.

&&

$$
SYNOPSIS...Fig/JM
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...Fig
AVIATION...MET
MARINE...Fig/JM
HYDROLOGY...Fig/JM
TIDES/COASTAL FLOODING...
EQUIPMENT...