000
FXUS61 KOKX 201006
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
606 AM EDT Mon Aug 20 2018

.SYNOPSIS...
High pressure from the Canadian Maritimes will move slowly
farther northeast through early Tuesday. Low pressure moving
northeast across the upper Great Lakes into Ontario and Quebec
will send a warm front toward the area late Tuesday, followed by
a cold frontal passage on Wednesday. High pressure will then
settle over the area late this week and start to weaken late in
the weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
An upper level disturbance in the form of a 500mb vorticity
vorticity maximum will be moving slowly northeast of the region
today.

Models are in general agreement with some very light QPF today
along the coast as clouds linger there. The NE flow at around 10
to 20 mph will continue to provide more stable low level flow,
relatively cooler and a little less humid.

A lingering trough axis near the surface and the moisture rich
boundary layer with NE flow will enable some light rain or
drizzle along the coast where there will be a little more
convergence.

Initially mainly dry conditions are anticipated but POPs
increase in the afternoon with the high pressure area weakening
and translating farther northeast away from the local region.

High temperatures forecast today are mainly in the mid to upper
70s.

There is a moderate risk of rip currents at the Atlantic Ocean
beaches for today.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
A lingering slight chance of light rain or drizzle along the
coast is forecast tonight but without much forcing present,
think this will be brief and POPs are below chance (slight
chance). Left late evening and overnight dry going into
Tuesday.

A larger amplitude trough moves closer Tuesday and this will
eventually bring higher POPs for showers into the region. A
warm front will approach the region at the surface. Its surface
parent low will move from the Great Lakes into Quebec. Went with
slightly cooler high temperatures compared to the previous day.
Models are not conveying much diurnal instability so left out
thunder.

For Tuesday, the risk for rip currents at Atlantic Ocean beaches
will be moderate with winds becoming more E-SE and easterly
swell.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Low pressure over the Great Lakes continues to lift northward into
Canada. Meanwhile. an upper level trough approaches from the west. A
warm front should be over or just about to move into the region
around the time the long term period starts. As a result, shower
coverage should increase, with a few heavier showers and
thunderstorms possible late Tuesday night. A cold front will then
move across the region on Wednesday at least for NYC metro and
points west, but the front could progress slowly enough to allow for
instability to build over eastern CT/Long Island and spark another
round of showers/tstms mainly in the late morning and early
afternoon.

Drier weather is then expected Wednesday night, as high pressure
starts to build into the region. Expect a period seasonably warm and
less humid days coming up for Thursday-Saturday.

The high begins to weaken and slide east Saturday night and Sunday.
meanwhile, a weak upper level shortwave will pass north of the
region. This may set off a few showers late this weekend.

&&

.AVIATION /10Z MONDAY THROUGH FRIDAY/...
A weak frontal boundary will remain stationary across the Mid
Atlantic states through today, meanwhile, high pressure noses
in from the north. The high retreats tonight as a warm front
begins to approach from the south.

VFR to scattered MVFR ceilings will become more widespread
MVFR into early this morning, from the east to west, at KGON,
KISP, and KBDR. MVFR ceilings may move into the NYC metro before
13Z and continue to indicate this with a tempo.

VFR is expected after 12Z, except MVFR remaining at KBDR, KISP,
and KGON. Here ceilings may briefly improve to VFR in the
afternoon before lowering once again. Amendments will be likely
at these terminals Monday.

An east to northeast flow is forecast through the TAF period
with winds increasing to 10 to 14 KT.

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

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

KJFK TAF Comments: MVFR ceilings are possible before 13Z. There
is uncertainty of this occurring and indicate with a tempo.
MVFR ceilings return this evening.

The afternoon KJFK haze potential forecast is YELLOW, which
implies slant range visibility 4-6SM outside of cloud.

KLGA TAF Comments: MVFR ceilings are possible before 13Z. There
is uncertainty of this occurring and indicate with a tempo.
MVFR ceilings return this evening.

The afternoon KLGA haze potential forecast is GREEN, which implies
slant range visibility P6SM outside of cloud.

KEWR TAF Comments: MVFR ceilings are possible before 13Z. There
is uncertainty of this occurring and indicate with a tempo.
MVFR ceilings return this evening.

The afternoon KEWR haze potential forecast is GREEN, which implies
slant range visibility P6SM outside of cloud.

KTEB TAF Comments: MVFR ceilings are possible before 13Z. There
is uncertainty of this occurring and indicate with a tempo.
MVFR ceilings return early this evening.

KHPN TAF Comments: MVFR ceilings are possible before 13Z. There
is uncertainty of this occurring and indicate with a tempo.
MVFR ceilings return this evening.

KISP TAF Comments: There is uncertainty if MVFR ceilings will
develop and then remain into this morning. There is a low chance
that this occurs. VFR is more likely. Amendments for ceilings
possible today.


.OUTLOOK FOR 06Z TUESDAY THROUGH THURSDAY...
.Mon night...MVFR with areas of drizzle and fog. Local IFR.
.Tue...Becoming VFR in the morning.
.Tue Night-Wed...Shower/tstm likely with MVFR conditions.
.Thu-Fri...VFR.

&&

.MARINE...
Wave heights overall on the ocean have been running a little
less than forecast. Did not want to take down any part of SCA
or change end time of it yet until a steady below SCA trend is
seen with ocean buoys. Expecting SCA gusts and ocean waves
today, mainly for the eastern ocean zones. For tonight and
Tuesday, mainly below SCA conditions are forecast.

Ocean seas will likely build to SCA levels late Tue night into Wed
as SW flow increases to around 20 kt. These elevated seas may linger
out east into Wed night. Otherwise, conditions should remain below
small craft levels.

&&

.HYDROLOGY...
No hydrologic impacts are expected through Tue.

Showers and thunderstorms, some with heavy rain, may be possible
Tuesday night into Wednesday morning with a passing of a frontal
system. PWATs increase to over 2 inches and deep layer SW flow,
could result in the potential for urban and poor drainage flooding
from NYC north/west. Flash flood potential is not out of the
question with low FFG values especially over NE NJ, but does not
look widespread.

&&

.EQUIPMENT...
NYC NOAA Weather Radio Station KWO-35 (162.55 MHz) remains off
the air for an extended period of time.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ350-
     353-355.

&&

$$
SYNOPSIS...BC/JM
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...BC
AVIATION...MET
MARINE...BC/JM
HYDROLOGY...BC/JM
EQUIPMENT...

NWS OKX Office Area Forecast Discussion