000
FXUS61 KOKX 011421
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
921 AM EST Fri Dec 1 2023
.SYNOPSIS...
A weak wave of low pressure will impact the region late today
through tonight. Another low moving toward the Great Lakes on
Sunday will weaken, with a secondary low forming south of Long
Island Sunday evening and moving east into the Atlantic later
Sunday night into Monday. High pressure will return for Monday
and Tuesday. Low pressure will then form off the southern Mid
Atlantic coast and move out to sea on Wednesday, followed by
building high pressure on Thursday.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
The forecast remains mostly on track. The only notable
adjustment for this update were increasing POPs 20-30% for
northern and western portions of the CWA to account for 12Z CAMs
showing a line of rain pushing through preceding the main
system, which is also mentioned more in the discussion below.
The day begins with weak high pressure in place, which should hold
off any rainfall during the morning with maybe an exception towards
noon well north and west as lift is enhanced here with the passage
of an upper jet streak. Rain otherwise becomes likely generally west
to east late in the day into tonight as isentropic lift and mid-
level shortwave energy shift through. Mid-levels dry out late
tonight with still some lower level lift potentially producing some
drizzle with the remnant low level moisture. Models have trended
weaker regarding wind speeds at the base of a low level inversion
late tonight, so with not as high of a chance that turbulent mixing
disrupts fog formation, coupled with light and variable surface
winds, have added areas of fog to the forecast.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
Low level moisture becomes even more shallow on Saturday along with
weaker lift. Have therefore gone with a dry forecast outside of any
potential drizzle very early on. Remaining mostly cloudy however,
but temperatures will still be above normal in the mid 50s. The next
area of low pressure approaches from the south during Saturday
night. Rain becomes likely for mainly southern areas after midnight.
Temperatures remaining above normal with cloudy conditions.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
Rain expected for Sunday into Sunday night as primary low pressure
weakens to the west and a new center forms just south of Long Island
Sunday evening. Cyclonic low level flow in its wake as the low moves
well out to sea should maintain a fair amount of clouds for Mon in
its wake, along with a gusty W wind. Both days should feature temps
a few degrees above normal, with colder wx returning Mon night and
beyond as a weak secondary cold front moves through.
Mostly dry wx forecast from that point on. A digging nrn stream
shortwave trough should initiate Miller B type cyclogenesis E of
Hatteras on Wed with the global models showing the low moving due E
out to sea, but this situation bears some watching as it could be
less progressive than forecast as previously noted given model
tendency to underdo western Atlantic ridging downstream of the
digging trough, also presence of some ridging aloft near Greenland
and a 50/50 upper low, all of which might allow the low to get close
enough for its precip shield to graze the coast before exiting.
Forecast carries slight chance PoP for snow/rain showers on land and
chance PoP just offshore.
High pressure is then progged to build in for later in the week.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
High pressure will remain to the S today. Low pressure will
then pass to the W tonight.
VFR for most of the day, then MVFR developing possibly as early
as 22Z-23Z with light rain, but more likely after 00Z-01Z.
Areas of IFR likely after 02Z-03Z with light rain or drizzle.
SSW winds 5-10 kt should back more S this afternoon. Winds
become light/variable in most spots tonight, but may veer SW
along the coast.
...NY Metro(KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled AMD expected.
OUTLOOK FOR 12Z SATURDAY THROUGH TUESDAY...
Saturday: Fog/drizzle with IFR cond should improve to MVFR at
KGON/KISP by 14Z-15Z and to VFR elsewhere. VFR at all
terminals by afternoon.
Saturday night: Rain likely with possible MVFR cond late.
Sunday: Rain expected with IFR cond likely. N winds G15-20kt
NYC metro/coast late at night.
Monday: MVFR possible early north/east of the NYC metros,
otherwise VFR. W winds G20kt, becoming NW G20-25kt at night.
Tuesday: VFR. NW winds G15-20kt.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Expecting an extended period of sub-advisory conditions through
at least Sunday with winds becoming lighter today and remaining
on the the light side well into the weekend. There could be a
brief period Saturday afternoon where a swell builds to 5 ft on
the eastern ocean waters, but not anticipating the need for an
advisory just yet.
A period of SCA cond expected for the ocean waters from Sunday night
into Tue AM, with W flow gusting to 25 kt and seas building to 5-6
ft in the wake of departing low pressure, then shifting NW with
passage of a secondary cold front with gusts increasing to 30 kt and
seas to 5-7 ft. SCA cond likely on the non ocean waters Mon night
following this fropa as well, with NW flow gusting to 25 kt.
&&
.HYDROLOGY...
No hydrologic impacts expected with today/tonight`s rainfall. Rainfall
of about 3/4 inch expected Sunday into Sunday night. Light to moderate
intensity and long duration preclude any issues.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JC/BG
NEAR TERM...JC
SHORT TERM...JC
LONG TERM...BG
AVIATION...BG/JM
MARINE...JC/BG
HYDROLOGY...JC/BG