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000
FXUS61 KOKX 191339
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
939 AM EDT Wed Sep 19 2018

.SYNOPSIS...
High pressure builds down from the Canadian Maritime Provinces
through Thursday. A warm front passes to the northwest Thursday
night, followed by a cold front crossing the Tri-State late
Friday night and Saturday morning. The front settles to the
south into early next week as high pressure builds to the north.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Deep layered ridging builds in from the southwest today. There
should be sufficient subsidence as a result to keep things dry.

Forecast is generally on track with previous thinking to cloud
forecast today. Have made some adjustments to sky mainly for
the first half of the day based on latest sat imagery. Unclear
how far west the stratus deck over eastern areas will make it,
which also makes the temp forecast challenging. Western areas
should be warmer than eastern and tried to reflect that in the
MaxT forecast. A blend of the CMCReg (which was also the
starting point for the cloud forecast) and the BCCONSRaw was
used for highs, although MaxT forecast has high bust potential.

There is a moderate risk for the meteorological enhancement of
rip current formation at Atlantic Ocean Beaches Today.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
Deep layered ridging continues to build in from the SW through
Thursday. Continue to believe that subsidence under the
building ridging should keep things dry. However, associated
subsidence inversion should keep low clouds that moved in today
around through tonight and quite possibly into Thursday morning.
It appears that enough dry air should be transported down from
aloft (due to the subsidence under the ridge) that the clouds
should abate (to at least partly vice mostly cloudy) by around
mid morning, except for possibly over far western zones, where
elevation could help keep things mostly cloudy through the day
(harder to scourer out lo level moisture once outside of the
coastal plain and into foot hills/ridge and valley regime).

For lows tonight, weighed towards warmest guidance due to cloud
cover. For now used a blended approach for highs on Thursday.
However, if the cloud cover does not dissipate, could end up 5
or so degrees cooler than forecast.

There is a moderate risk for the meteorological enhancement of
rip current formation at Atlantic Ocean Beaches through Thursday.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Upper level ridge axis shift to the east Fri morning as a
shortwave trough over the upper Midwest dampens while tracking
through New England Fri night. Quasi zonal flow then remains
through the weekend with the H5 flow amplifying across the CONUS
early next week, although differences in timing and amplitude
are noted.

At the sfc, a warm front associated with strengthening low pres
over the upper Midwest, will pass to the NW Thu night as the low
lifts into southern Ontario. The low will continue to track NE
with it`s attending cold front passing through late Fri
night/Sat morning. The best upper dynamics pass to the north so
expecting a weakening trend as it moves through, thus no more
than 30-40 PoPs are warranted.

How far south the front pushes remains uncertain with the flow
aloft becoming nearly parallel to it. Latest trends in the EC
push it into the Mid Atlantic region, while the GFS is much
closer to the local area. If the GFS ends up verifying, southern
portions of the forecast area, could see some rain Sat night
into Sun as a wave of low pressure tracks along the boundary.
Have kept the forecast dry for now. Strong Canadian high pres
builds in from the N into early next week, shifting into the
Canadian Maritimes Mon night/Tue. Meanwhile, the old frontal
boundary to the south will begin to lift back to the N passing
through the local area on Tue.

Temperatures vary through the period. Temps are expected to be a
few degrees above normal on Fri as the area sits in the warm
sector. Once the cold front passes, temps likely fall back to
near normal Sat, below normal Sun and Mon, then back to near
normal on Tue.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
High pressure builds towards the region today, and over the
area on Thursday.

Increasing clouds from the NE thru the day. Heights generally
in the 3-4k ft range, with the lowest cigs ne of NYC. As a
result, mainly VFR in the city, but mvfr developing elsewhere.
The clouds are expected to linger thru the entire TAF period,
with perhaps improvement to SCT at times.

Winds veer to the NE today. Some gusts to 15 kt possible aft
15z, then speeds in general decrease aft 20-22z.

     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: There is a chc that 3000 ft cigs develop
today.

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

KLGA TAF Comments: There is a chc that 3000 ft cigs develop
today.

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

KEWR TAF Comments: There is a chc that 3000 ft cigs develop
today.

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

KTEB TAF Comments: There is a chc that 3000 ft cigs develop
today.

KHPN TAF Comments: Amendments possible for timing of cigs.

KISP TAF Comments: Amendments likely for timing of cigs.


.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
.Thursday...VFR.
.Thursday night...Slight chance of showers with MVFR possible.
.Friday-Friday night...VFR during the day, then a chance of
showers and thunderstorms with MVFR at night.
.Saturday-Sunday...An early shower Saturday, then VFR through
the weekend.

&&

.MARINE...
Seas over the coastal ocean waters west of Fire Island Inlet
have fallen below 5 ft, so have cancelled the Small Craft
Advisory (SCA) there. East of Fire Island Inlet, there could
be a few hours of seas below 5 ft, mainly this morning, before
seas build back on strengthening NE winds. Expect seas to build
back to 5 ft west of Fire Island Inlet by this evening. As a
result, have extended the SCA on the coastal ocean zones east of
Fire Island Inlet through tonight and issued a new SCA for the
coastal ocean waters west of Fire Island Inlet for tonight.

On Thursday, the seas around 5 ft should continue on the
coastal ocean waters, but am not quite at the required 80
percent confidence in this to extend the SCA through then.

Sub-SCA conditions are expected on the non-ocean waters through
Thursday, and on all waters Thursday night.

A tightening pres gradient ahead of an approaching cold front is
expected to produce SCA conds on most of the local waters late
Fri/Fri night. Winds should diminish by Sat morning, although seas
on the ocean will likely linger a bit longer. Sub Small Craft
Advisory conditions are then expected on all waters through the
weekend.

&&

.HYDROLOGY...
No significant hydrologic impacts are expected through Tuesday
of next week.

&&

.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 from 6 PM this evening to 6 AM EDT
     Thursday for ANZ355.
     Small Craft Advisory until 6 AM EDT Thursday for ANZ350-353.

&&

$$
SYNOPSIS...24/Maloit
NEAR TERM...BC/Maloit
SHORT TERM...Maloit
LONG TERM...24
AVIATION...JMC/IRD
MARINE...24/Maloit
HYDROLOGY...24/Maloit
EQUIPMENT...