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901
FXUS61 KOKX 141815
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
115 PM EST Fri Dec 14 2018

.SYNOPSIS...
High pressure weakens over the region today as a broad area of low
pressure approaches from the southwest. This storm system will
remain to centered our south as it tracks off the Mid-Atlantic
Coast on Sunday. High pressure builds to start the week.
Another system looks to impact the region towards the end of
next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Updated the forecast to raise high temperatures across portions
of Long Island and coastal Connecticut, where warm advection has
been stronger than previously expected.

High pressure weakens through the day, however low level moisture,
primarily below 900mb, will remain trapped beneath an inversion and
keep us cloudy all day. Some mid-level lift eventually arrives with
a passing shortwave this afternoon, but even before this, models are
in pretty good agreement with some isentropic/low level lift.
Thinking is that this will result in areas of drizzle or even
light rain with minimal accumulation. Best overall chances
appear to be in the vicinity of NYC and points north and west,
where light returns are beginning to show on radar.

Highs around 50 for coastal areas with mid and upper 40s
inland.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
Models agree that low level moisture and lift diminish this
evening, but is replaced with increasing mid and upper level
moisture. It`s not until the late night hours where low level
moisture increases again, in response to low pressure approaching
from the SW. Will go with increasing PoPs as the night progresses.
The lack of deep moisture through the column should preclude heavy
rainfall, but it could still fall moderately late at night.

The low pressure system shifts east on Saturday, and high pressure
will start to build in from the north at the same time. This will
have the northern extent of rainfall shifting south across the area
through the day. Most of the rain probably falls by noontime, but
still have chc PoPs during the afternoon hours. Both low and high
temperatures tonight and Saturday will be above normal.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
The long term continues with unsettled weather as a closed low
slowly moves off the Mid-Atlantic coast into Sunday reintroducing
rain into the forecast. Additional rainfall amounts will range
between 0.5 to 0.75 inches. Currently, the temperatures look to
remain above freezing, and therefore expecting rain. The cold air
doesn`t seem to infiltrate the region until after the bulk of the
precip has ended. However, as the low pulls away to the northeast on
Monday, there is a chance for a few light showers/snow showers.

High pressure then builds in from the west into early next week
bringing a period of dry weather. A cold front will sweep through
the northeast late Monday bringing in cooler temperatures for
Tuesday and Wednesday.

Another low pressure and associated frontal system looks to impact
the region towards the end of next week.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
High pressure continues to drift away from New England this
afternoon, while low pressure then approaches the Mid Atlantic
states tonight. This low then tracks well south of the region on
Saturday.

MVFR conditions expected for all but KGON through this
afternoon as moisture remains trapped under inversion. Window
for improvement to VFR for evening push as daytime instability
wanes. Conditions expected to fall back to MVFR tonight and
continue through Sat morning push, with northern edge of light
rain shield working through the region. If the rain shield works
farther north than anticipated, IFR conds are possible, but low
probability at this time. Gradual improvement to VFR expected
in wake of low pressure late Sat morning into Sat afternoon.

Light E/SE at less than 10 kt, with light and variable winds
tonight. N/NE winds develop late Sat morning into Sat
afternoon, with a period of 15 to 20 kt gusts possible for
NYC/NJ metro terminals.

     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: MVFR cigs likely through this afternoon,
with potential for VFR developing towards 00z. MVFR conds
likely re-develop after 06z in light rain and continue for Sat
morning push, with low prob for IFR.

KLGA TAF Comments: NE winds likely shift to SE between 19 and
22z, but may remain NE into evening push but weakening. MVFR
cigs likely through this afternoon, with potential for VFR
developing towards 00z. MVFR conds likely re-develop after 06z
in light rain and continue for Sat morning push, with low prob
for IFR.

KEWR TAF Comments: MVFR cigs likely through this afternoon,
with potential for VFR developing towards 00z. MVFR conds
likely re-develop after 06z in light rain and continue for Sat
morning push, with low prob for IFR.

KTEB TAF Comments: MVFR cigs likely through this afternoon,
with potential for VFR developing towards 00z. MVFR conds
likely re-develop after 06z in light rain and continue for Sat
morning push, with low prob for IFR.

KHPN TAF Comments: MVFR cigs likely through this afternoon,
with potential for VFR developing towards 00z. MVFR conds
likely re-develop after 06z in light rain and continue for Sat
morning push, with moderate prob for IFR.

KISP TAF Comments: MVFR cigs likely through this afternoon,
with potential for VFR developing towards 00z. MVFR conds
likely re-develop after 06z in light rain and continue for Sat
morning push, with low prob for IFR.

.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
.Saturday Afternoon...Improvement to VFR. N/NE gusts 15 to 20 kt
possible.
.Saturday Night and Monday...MVFR/IFR in rain likely. Potential
for wintry mix across interior terminals Sunday Night into
Monday AM. Improving conds Sun Aft. Potential NE G20-25kt Sat
Night/Sun becoming NW Sun NIght/Mon.
.Monday Night into Tuesday...VFR. NW Wind G20-30kt possible.
.Tuesday Night into Wednesday...VFR. NW Wind G15-20kt possible.

&&

.MARINE...
Seas on the ocean should start just below 5 ft, then subside through
the day as winds and swell diminish. Sub-advisory conditions for all
waters then continue tonight and Saturday with relatively light
winds for most of the time, however winds should increase Saturday
afternoon with gusts perhaps getting close to 25 kt towards
evening.

Small craft conditions are likely Saturday night into Sunday as low
pressure moves off the Mid-Atlantic Coast across the ocean waters,
southern and eastern bays and possibly New York Harbor.

Ocean seas will build to SCA levels Saturday night and remain
elevated into Wednesday.

&&

.HYDROLOGY...
Between 0.50" and 1.25" of rainfall is expected tonight through
Sunday night. The highest rainfall amounts are currently expected
across portions of northeastern New Jersey, NYC, and Long Island. No
widespread flooding is expected due to antecedent dry conditions in
addition to the potential of a long break in any rainfall during the
Saturday afternoon/evening time frame.

&&

.EQUIPMENT...
NYC Central Park winds are out of service until further notice.
Loss of data is due to a severed cable. Parts are on order.

NYC NOAA Weather Radio Station KWO35 (162.55 MHz) will remain off
the air for an extended period of time.

&&

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

&&

$$
SYNOPSIS...CB/JC
NEAR TERM...JC/MD
SHORT TERM...JC
LONG TERM...CB
AVIATION...NV
MARINE...CB/JC
HYDROLOGY...CB/JC
EQUIPMENT...