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000
FXUS61 KOKX 201127
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
727 AM EDT Wed Mar 20 2019

.SYNOPSIS...
High pressure will slide offshore today. A frontal system then
impacts the area Thursday into Thursday night. Deepening low
pressure lifts well to the north Friday into Saturday as high
pressure builds Sunday. The high will give way to a cold front
Monday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Light southerly flow has developed as high pressure slides to
the east. With plenty of sunshine, highs will rise into the
upper 40s to lower 50s, near normal for this time of year.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
With a frontal system approaching from the west and a surface
low developing along the southeast coast, clouds will gradually
increase this evening, although the majority of the overnight
hours are expected to remain dry.

Rain chances begin to increase towards daybreak for areas west
of the city, with much of the region from New York City to the
east remaining dry until after sunrise. Precipitation then
gradually overspreads the area from southwest to northeast
through the day on Thursday and continues into Thursday night
before tapering off after midnight. While the vast majority of
the precipitation is expected to fall as rain, the potential
does exist for a rain/snow mix for a few hours well north and
west of New York City Thursday morning if precipitation is able
to move in fast enough. Any snow that does fall in this area is
not expected to accumulate.

Models are in generally good agreement with the track of the
southeastern low, taking it near or just east of New York City
Thursday night before continuing off to the northeast Friday
morning. While timing differences still remain, the overall
trend with this system over the past 24 hours has been for slower
precipitation onset Thursday morning and a westward shift in the
axis of heaviest precipitation. Rainfall amounts are expected to
generally be around an inch from Thursday morning through Friday
morning, with the highest totals across northeastern New Jersey,
New York City and into southwestern Connecticut.

With plenty of cloud cover, temperatures both Wednesday night
and Thursday night are expected to be several degrees above
normal, generally in the mid 30s to lower 40s. Highs on Thursday
are expected to be near normal, in the upper 40s to lower 50s.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Two separate shortwaves pivoting around the main trough will
consolidate into a closed low over the northeast Friday that will be
slow to lift. As this develops, the sfc low that is passing across
eastern sections of the CWA early Friday will move northward in
time, deepening rapidly as it does so. As the shortwave dives out of
SE Canada, forming the closed low, additional showers will likely
move across portions of the area Friday afternoon and into the
evening before lifting northward. Cyclonic flow will result in
additional and persistent clouds Friday night into Saturday, but
drier conditions are ushered in thanks to westerly downslope flow.

As this low lifts northeast, brief ridging this weekend flattens,
then heights fall once again early next week as shortwave dives out
of Canada, lowering heights across the northeast.

Before high pressure builds Sat night and Sunday, strong W/NW winds
are expected behind the deepening low, increasing later Friday, and
remaining quite strong Friday night and Saturday before diminishing
Sat night.

The high passes south and east Sunday, and a cold front will
approach from the northwest Monday, passing Monday night. High
pressure builds behind this front.

Latest ECMWF is now indicating a dry frontal passage Monday, while
GFS is much wetter tapping moisture from the south as it advects
northeast along the front. Differences are noted in the upper levels
as GFS progs a slightly more amplified trough as it moves across the
northeast when compared to ECMWF. Both the ECMWF and Canadian global
prog a stronger shortwave across the midwest during the Monday-
Tuesday time frame. Will maintain chance pops for now on Monday.

As for temps, near normal readings Friday will lower to below normal
as colder air advects in Friday night-Saturday. Westerly flow
Sun along with rising heights will result in a warming trend for
Sunday- Monday (although Monday may be tricky depending on
speed of front). Temps fall back below average on Tue as colder
air settles in behind the front.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
High pressure gradually shifts offshore through tonight. Low
pressure develops along the southeast coast late tonight and tracks
north towards the terminals Thursday morning.

Light SW flow increases this morning under 10 kt, gradually backing
to the S-SE in the afternoon 10-12 kt. SE winds diminish after 23z
before backing towards the E and increasing late tonight and
Thursday morning.

VFR through much of the TAF period with conditions beginning to
lower to MVFR in developing -RA Thursday morning.

  ...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: Winds could shift to the SE 1-2 hours sooner than
forecast this afternoon.

The afternoon KJFK haze potential forecast is GREEN...which implies
slant range visibility 7SM or greater outside of cloud.

KLGA TAF Comments: Winds could shift to the SE 1-2 hours sooner than
forecast this afternoon.

KEWR TAF Comments: Winds could shift to the SE 1-2 hours sooner than
forecast this afternoon. An occasional gust 15 to 18 kt possible
around 19-22z.

The afternoon KEWR haze potential forecast is GREEN...which implies
slant range visibility 7SM or greater outside of cloud.

KTEB TAF Comments: Winds could shift to the SE 1-2 hours sooner than
forecast this afternoon.

KHPN TAF Comments: No unscheduled amendments expected.

KISP TAF Comments: No unscheduled amendments expected.

.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
.Thursday...MVFR/IFR in rain. SE G20-25kt. Chance of LLWS in the
evening.
.Friday...Mainly VFR, chance of rain/snow showers inland and rain
showers near coast. W-NW G25-30kt.
.Saturday...VFR. NW G25-35kt
.Sunday...VFR.

&&

.MARINE...
Quiet conditions are expected on the waters through tonight as
high pressure slides offshore. Winds and waves will then
increase through the day on Thursday in response to an
approaching area of low pressure, likely reaching SCA criteria
on the ocean waters by Thursday afternoon. Winds and seas then
remain elevated through Thursday night.

As low pressure passes through early Friday, then deepens as it
moves northward, westerly winds will increase, and seas will build
or remain elevated.

These windy conditions will continue Friday night and Saturday as
the deep low is slow to depart to the northeast. High pressure
builds Sunday, and winds will diminish, allowing seas to
subside.

&&

.HYDROLOGY...
No hydrologic impacts are expected through tonight. Around an
inch of rain is possible Thursday morning through Friday
morning, which could result in some minor poor drainage
flooding. Thereafter, no hydrologic impacts are expected through
Tuesday.

&&

.TIDES/COASTAL FLOODING...
Astronomical tides will be rather high due to the full moon, and
minor coastal flooding is possible beginning Thursday. At this time,
it appears that the Thursday night high tide cycle will be the most
vulnerable. Would expect widespread minor to perhaps locally
moderate flooding during that tide cycle.

Otherwise, local minor is possible during the daytime high tide
cycle Thursday, and possibly Friday as well.

&&

.EQUIPMENT...
NYC NOAA Weather Radio Station KWO35 (162.55 MHz) remains off
the air.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$
SYNOPSIS...FEB/PW
NEAR TERM...FEB/PW
SHORT TERM...FEB
LONG TERM...PW
AVIATION...DS
MARINE...FEB/PW
HYDROLOGY...FEB/PW
TIDES/COASTAL FLOODING...
EQUIPMENT...