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000
FXUS61 KOKX 211756
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
156 PM EDT Wed Oct 21 2020

.SYNOPSIS...
The front that stalled northwest of the region will move farther
north as a warm front today. A cold front will be approaching
from the west tonight and move through the region early
Thursday. High pressure builds in thereafter but the center of
it will stay to the north through Thursday night. High pressure
will be sliding across New England Thursday night into Friday.
Another cold front will approach on Saturday, and push through
Sunday. High pressure briefly moves through on Sunday, before a
slow moving frontal system affects the region for early next
week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A stalled front will move farther northeast today, which may
provide some weak lift for showers that will move across eastern
Long Island and southeastern Connecticut. However, coverage
will be sparse, so only a slight chance for showers is expected
through early to mid afternoon. The local region will be in the
warm sector with another developing frontal system in Quebec.
850mb temperatures increase by about a degree C compared to the
previous day. More southerly flow will keep coastal locations
across Southern Connecticut and Long Island a few degrees
cooler. Max temperatures are mainly in the lower 70s.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
There will be a cold front approaching the region tonight and
eventually moving into and through the region by early Thursday.
There will be some extra clouds tonight from this feature but
weather is expected to remain dry. Low levels are expected to
become saturated again so another round of fog could very well
be in store for the area. Lows were a blend of MOS consensus and
NBM, ranging from the mid 50s to mid 60s.

For Thursday, the front will move across early in the day, with
a switch to more westerly low level flow. The pressure gradient
is weak so the wind speed will be light. High pressure will
start building in from the north. More of a northwest flow
stays across the interior while the coast will have more
variability in the wind direction. Drier conditions and more
sunshine will lead to a warmer day. Highs forecast are in the
low to upper 70s.

For Thursday night, high pressure moves to more northeast of the
region, with the center of high pressure moving from Northern
New England into the Canadian Maritimes. More of a southeast
flow will develop across the region. Some weak convergence is
indicated by multiple numerical weather prediction models, so a
slight chance of showers was added to the forecast. Once again,
low levels look to become nearly saturated so patchy fog and
patchy drizzle was added to the Thursday night forecast. Lows
forecast are in the mid 50s to lower 60s.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Models continue good agreement with the region remaining under
the influence of western Atlantic ridging for late week, as
longwave troughing dominates the northern half of the western
and central US. The ridging gets suppressed this weekend as an
energetic shortwave slides through southern Ontario and Quebec
Friday Night into Saturday night allowing the eastern flank of
the upper trough to slide a bit farther east, with a fast
cross-CONUS SW flow developing aloft. This upper flow will help
deflect Hurricane Epsilon NE away from the coast heading into
this weekend, eventually shearing into this flow east of the
Canadian Maritimes.

A transition to a maritime airmass expected Thu Night into
Friday, with gusty E flow between high pressure sliding off the
Canadian maritimes and Epsilon making its closest approach.
Long period energetic swells from Epsilon will be building to
the shoreline as well Thu night into Friday, lingering through
the weekend.

The next chance of a few showers looks to be late Saturday into Sat
Night as a somewhat stronger cold front sags into the region. The
front may briefly clear the region Sunday, before returning as a
warm front Sunday Night into Monday. Then increasing potential for
an extended period of unsettled weather Mon into Wed as the longwave
trough amplifies across the western US, and northern and southern
stream phase heading into early/mid next week, orientating a fast
upper flow over the area. This will have an approaching cold front
only slowly sliding through the area Mon into Wed, with several
waves of low pressure and resultant periods of showers (and even
some embedded thunder) tracking along it. Low predictability on
rainfall amounts this far out, but overall an unseasonably mild and
very moist airmass will be in place for late October early next
week.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A cold front passes late tngt, then stalls near the region on
Thu.

Gradual improvement will continue this aftn. VFR is still
expected by 19-20Z for most areas. MVFR and lower is likely to
develop again tngt. LIFR is possible especially E of the NYC
arpts. Improvement to VFR is expected on Thu, however, if the
front stalls too close to the area MVFR or lower will linger
thru the day.

 ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

Exact timing of improvement today uncertain. There is the
potential that 1/4sm FG develops at some of the arpts tngt,
including JFK. Confidence was too low to included in the TAFs
attm. There is the potential for MVFR or lower to linger thru
much of Thu if the front does not pass far enough S of the area.

.OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY...
.Rest of Thu...Mainly VFR in the aftn. MVFR or lower possible
Thu ngt, especially E of NYC terminals.
.Fri...MVFR or lower possible. Lgt S flow.
.Sat...Becoming VFR. Winds becoming NW less than 25kt.
.Sun...VFR with lgt N flow.
.Mon...MVFR or lower possible. Strong SW flow possible.

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

&&

.MARINE...
Visibilities have improved across the coastal waters and the
Dense Fog Advisory that was in effect has been cancelled.
Visibilities may become patchy dense at times, through early
afternoon.

Otherwise, sub-SCA conditions will continue across all
waters through early Thursday morning. Then, long period swell
from distant Hurricane Epsilon will build ocean seas to 5 ft
Thursday afternoon. Long period energetic ocean swells from
Hurricane Epsilon are likely to reach 5-8 ft Thursday night into
Friday and likely continue into the weekend. Please refer to
National Hurricane Center products for further details on
Epsilon.

SCA in effect for the ocean from 11AM Thursday through Friday.
SCA seas on the ocean could very well extend into the weekend.
Winds will remain below SCA in a weak flow regime.

&&

.HYDROLOGY...
No hydrologic concerns anticipated through next week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 11 AM Thursday to 6 PM EDT Friday
     for ANZ350-353-355.

&&

$$
SYNOPSIS...JM/NV
NEAR TERM...JM/JP
SHORT TERM...JM
LONG TERM...NV
AVIATION...JMC
MARINE...JM/NV
HYDROLOGY...JM/NV