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fxus61 kokx 232337 

Area forecast discussion
National Weather Service New York New York
737 PM EDT Fri Jun 23 2017

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/...
a severe tstm watch has been issued for nern New Jersey until 10pm with
a primary threat of damaging winds.

Made minor update to temps and dewpoints to reflect current
observations. Otherwise, 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.


Short term /6 am Saturday morning through Saturday night/...
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 New Jersey 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

A moderate risk of rip currents is forecast for Saturday.


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 /00z Saturday through Wednesday/...
a cold front approaches this evening, then slowly moves through
the terminals by around 12 to 16z tomorrow morning. Initial area
of thunderstorms will gradually decrease in intensity as they
approach the western-most terminals this evening - including the
NYC Metro area. Additional showers and thunderstorms are
expected overnight with the approach of the cold front, with
heavy rain and reduced visibility possible at times.

Winds for most of the night will be from the south-southwest
with occasional gusts to around 20 kt possible. A low level jet
will move up the coast, with a brief period of low level wind shear possible
primarily at LGA/JFK/isp and to a lesser extent elsewhere.
Following the front tomorrow morning, winds will shift to west-
northwest with increasing gusts through the day and decreasing
cloud cover.

New York 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: amendments possible for showers and
thunderstorms. Wind gusts may be stronger than forecast for

Klga taf comments: amendments possible for showers and
thunderstorms. Wind gusts may be stronger than forecast for

Kewr taf comments: amendments possible for showers and
thunderstorms. Wind gusts may be stronger than forecast for

Kteb taf comments: amendments possible for showers and
thunderstorms. Wind gusts may be stronger than forecast for

Khpn taf comments: amendments possible for showers and
thunderstorms. Wind gusts may be stronger than forecast for

Kisp taf comments: amendments possible for showers and
thunderstorms. Low chance of IFR conditions developing
overnight. Wind gusts may be stronger than forecast for

Outlook for 00z Sunday through Wednesday...
Saturday night-Sunday night...VFR. Gusty west-northwest flow diminishing
in the evening.
Monday-Tuesday...VFR. A chance of shra/tsra Monday afternoon into


conditions on the waters are becoming more rough. Sub Small Craft Advisory winds
on non-ocean waters are expected through Saturday night. Ocean
stays in Small Craft Advisory through much of Saturday night. Less Small Craft Advisory 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


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.


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.


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


Okx watches/warnings/advisories...
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 2 am EDT Sunday for anz355.
Small Craft Advisory until 6 am EDT Sunday for anz350-353.


near term...jmc/jm
long term...fig

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