FXUS61 KOKX 091156

Area Forecast Discussion
National Weather Service New York NY
756 AM EDT Thu Jul 9 2020

Weak high pressure will remain over the area today. Low pressure
will then approach from the south tonight into Friday night,
followed by a series of weak fronts moving through Saturday into
early next week. High pressure builds in for the middle
of the week.


Forecast on track this morning. Some early morning fog/low
stratus should dissipate rather quickly after sunrise. Did issue
an SPS for some patchy dense fog which ends at 12z.

We are generally looking at another warm and humid day today as the
flow becomes more S-SE by afternoon. A mid level ridge, should help
reduce the amount of any convection today, however still can not
rule out a few isolated storms, so will continue to mention the
slight chance of a storm well north and west of NYC. Any storms that
do develop should end quickly this evening with the loss of any
daytime heating.

With respect to heat and headlines today, have decide to keep the
Advisory going for Urban NE NJ, where the best chance of 95
degree heat index values will be reached, but have decided to
drop the advisory for NYC. While a few heat indices may reach
95, it wont be widespread, and we wont hit the two day criteria
of 95 or greater.

Temperatures today are expected to reach the 80s and lower 90s. With
dew points in the upper 60s and lower 70s, heat index values will
be in the 90s just about everywhere (with the exception of the
south fork of Long Island and coastal New London county).

A moderate risk of rip current development will continue for the
ocean beaches via long period S swell.


An upper level ridge axis will move east, allowing a coastal
low pressure system to approach from the south. This low is
expected to become better organized and The National Hurricane
Center has increased the probability of this system becoming
tropical or a sub-tropical cyclone to 80 percent.

While all the forecast models bring the low up the coast, the
models really start to differ as the low approaches the local
region. The The 00z GFS remains furthest west with the low
track, taking the low over NJ into the Lower Hudson valley,
while the ECMWF, takes the low south of Long Island, then
passing just east of Montauk. The NAM, is in the middle with the
low passing over Long Island and up into Connecticut.

Either way, with the low approaching, rain chances increase early
Friday morning as it taps into subtropical moisture as it moves up
the coast. Rain chance will become likely for much of the day and
continue into Friday night.

A low confidence forecast continues for where the heaviest axis of
rain will fall, since this will be dependent on where the low
actually tracks. Either way, expect a wet period from Friday
into Friday night, with rainfall amounts 1 and 2 inches expected,
with locally higher amounts possible. PWATs values will range
between 2 and 2.5 inches, so expect the rain to be heavy at

In addition to the heavy rainfall, a few strong to severe
thunderstorms will be possible.

The low should move out of the area late Friday night into early
Saturday morning, with POPs gradually lowering late Friday night.

With continued onshore flow, tonight lows will remain mild, in
the upper 60s and lower 70s. Cloud cover and rainfall should
keep temperatures down a bit on Friday, with highs only in the
upper 70s and lower 80s.

High rip current risk is expected for Friday especially in the


An upper-level trough and its associated cold front will move
into the area Saturday, resulting in hot and humid conditions
and the increase chance for showers and thunderstorms on
Saturday and Sunday. The cold front will move off to the east
Monday, but the upper-level trough will remain overhead bringing
a potential for diurnal convection as well as a gradual trend
to a more seasonable airmass through early next week. High
pressure builds back across the area for the middle of the week.

Temperatures during the long term period will be in the upper
80s to near 90 with overnight lows in the upper 60s to mid 70s.


Weak high pressure will remain in control today. The effects of
low pressure to the south will begin to be felt along the coast
late tonight.

Low stratus with IFR conds has briefly intruded from the SW
into the NYC metros, and continues most elsewhere, with LIFR at
KSWF. These lower cigs should scatter by about 14Z, with VFR
for the rest of today. Light SSW winds winds back SE 5-10 kt by
afternoon, the back E and diminish most of tonight before
increasing toward daybreak Fri.

MVFR cond should arrive after midnight tonight, with IFR
possible at some of the coastal terminals, most likely KGON.

...NY Metro Enhanced Aviation Weather Support...

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

KJFK TAF Comments: Unscheduled AMD possible if lower cigs last
longer than fcst this AM. The afternoon haze potential forecast
is GREEN, which implies slant range visibility P6SM outside of

KLGA TAF Comments: The afternoon haze potential forecast is
GREEN, which implies slant range visibility P6SM outside of

KEWR TAF Comments: Unscheduled AMD possible if lower cigs last
longer than fcst this AM. The afternoon haze potential forecast
is GREEN, which implies slant range visibility P6SM outside of

KTEB TAF Comments: Unscheduled AMD possible if lower cigs last
longer than fcst this AM.

KHPN TAF Comments: No unscheduled AMD.

KISP TAF Comments: Unscheduled AMD possible if lower cigs last
longer than fcst this AM.

.Friday...MVFR or lower conds. Rain possibly heavy at times with
chance TSRA. E winds 15G20kt, backing SE in the evening, then
backing S and diminishing overnight.
.Saturday...MVFR or lower cond likely in SHRA/TSRA, especially in
the afternoon.
.Sunday and Monday...Continued chance mainly afternoon SHRA/TSRA,
with MVFR or lower cond possible.


The pressure gradient will remain relatively weak through
Thursday night. Conditions on the forecast waters will remain
below SCA thresholds.

A Small Craft Advisory is now in effect for Friday as low
pressure approaches from the south. Winds and seas are expected
to increase with gusts to 25 kt and seas building to 4-7 ft.
Expect the seas to remain elevated through Saturday, then
subside slightly on Sunday. Conditions will remain above SCA
conditions into early next week.


Urban and poor drainage flood threat exists with any
thunderstorm activity today. Main reason being a lack of steering
flow so thunderstorms will be slow moving. Convective coverage will
be more isolated today.

There is increasing potential for a moderate to heavy rainfall
event Friday into Saturday as a coastal system moves up the Mid-
Atlantic coast. Exact timing and track are still uncertain, but
this system has the potential to produce at least 1 to 2 inches
of rain with higher amounts possible with heavier bands.


NYC NOAA Weather Radio Station KWO35 (162.55 MHz) is undergoing
its final stages of testing, and is operating at full power.


NY...High Rip Current Risk from Friday morning through Friday
     evening for NYZ075-080-081-178-179.
NJ...Heat Advisory until 6 PM EDT this evening for NJZ004-006-
MARINE...Small Craft Advisory from 6 AM to 6 PM EDT Friday for ANZ350-



NWS OKX Office Area Forecast Discussion