000
FXUS61 KOKX 020234
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
934 PM EST Fri Dec 1 2023
.SYNOPSIS...
A weak wave of low pressure will impact the region through tonight.
Another low moving toward the Great Lakes on Sunday will weaken,
with a secondary low forming south of Long Island on Sunday. The
low pressure lifts northeast of the area Sunday night. A trough
of low pressure lingers on Monday with high pressure returning
for Tuesday. Another wave of low pressure develops off the
Middle Atlantic coast Wednesday, followed by high pressure for
Thursday. The next frontal system may approach next Friday.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
-- Changed Discussion --
Main area of rain was tracking ewd about 50kt across the cwa at
930 pm. Based on this timing, it clears Montauk around
midnight. Some light rain, dz, and fog will be left in its wake
for the remainder of the ngt. Lows will generally be in the 40s
with cloud cover, lgt winds, and llvl moisture in place.-- End Changed Discussion --
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/...
Low level moisture becomes even more shallow on Saturday along with
weaker lift due to a mid-level ridge nosing in. Because of this, a
dry forecast is expected much of Saturday, with possible breaks in
clouds in the afternoon, or just mid/high level clouds. Temperatures
will still be above normal in the mid 50s.
Rain is expected for Saturday night after midnight into Sunday night
as primary low pressure weakens to the west and a new center forms
just south of Long Island Sunday. Rain will likely be widespread as
there are strong signals for warm air advection allowing for more
lift. Some 12Z models also have strong FGEN occurring later on Sunday
because of the strong temperature gradient caused by cooler
temperatures to our north. Models have ample moisture available, as
well, with PWATs ranging between 1-1.4". The 90th percentile for
PWATs is around 0.95" with the max moving average at 1.4". Despite
this, not enough rain is expected to fall to lead to flooding
concerns.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
There has not been too much change with the forecast reasoning in
the extended. The global ensemble guidance is in good agreement on
the pattern over the northeast being dominated by mean upper
troughing through much of the upcoming week. The NBM was used for
this forecast update.
The highlights for the long term are:
*Low pressure will continue moving northeast through New England
Sunday night with rain ending from south to north through the night.
*Mainly dry conditions are then forecast Monday through the end of
the week.
*Temperatures will start out above normal Monday before trending to
seasonable or slightly below for the rest of the week.
Rain associated with low pressure will continue Sunday evening, but
diminishes from south to north through the night. Dry conditions are
expected to return by the morning rush hour on Monday. Skies will
likely remain mostly cloudy through Monday with a lingering trough
of low pressure of the area and broad cyclonic flow aloft. Highs on
Monday range from the upper 40s inland to the lower 50s near the
coast. Monday will also be breezy with potential of 20-25 mph gusts,
especially closer to the coast.
High pressure briefly returns for Tuesday. The flow aloft within the
upper trough begins to amplify Tuesday night as energy is progged to
dive southeastward towards the coast. A large majority of the global
models and ensembles keep low pressure development well south and
east off the Middle Atlantic coast late Tuesday night into
Wednesday. However, there are some ensembles members that have an
inverted trough near the area or the low close enough to support a
slight chance (20 percent) PoP. Based on the currently modeled
pattern, the upper trough amplification occurs too far offshore for
any impacts to the region. Temperatures Tuesday will be in the
middle and upper 40s and then only upper 30s to low 40s on
Wednesday.
The mean upper trough should push offshore later Wednesday into
Thursday. The deterministic runs diverge for the end of the week,
but ensemble means indicate a near zonal flow aloft with some
potential of a frontal system to approach on Friday. The forecast
remains dry with surface high pressure largely in control. Highs ins
the upper 30s to lower 40s Thursday trend closer to normal on
Friday.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
Offshore high pressure gives way to a wave of low pressure
moving near the local area tonight into early Saturday.
Rain tapers off overnight into early Saturday morning. Fog is
expected to develop into Saturday morning, and then fog is
expected to dissipate.
MVFR lowering to IFR overnight, lasting into Sat mrng. Some
localized sub-IFR is forecast outside of NYC terminals.
Improvement back to MVFR and eventually VFR expected during the
day Saturday. CIGs back down to MVFR and lower aft 00Z Sun.
Winds generally a 5-10 kt S-SW flow but with some variable
directions at times, especially overnight into early Saturday
morning as well as late Saturday afternoon into Saturday evening.
...NY Metro(KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of MVFR and IFR could be 1-3 hours off. Some fluctuation
between VFR, MVFR and IFR is possible tonight into Saturday.
OUTLOOK FOR 00Z SUNDAY THROUGH WEDNESDAY...
Saturday night: IFR likely.
Sunday: Rain expected. MVFR to IFR likely. W winds G15-20kt late at
night.
Monday: Mainly VFR. W winds G20-25kt, becoming more NW at night.
Tuesday: Mainly VFR. NW winds G15-20kt.
Wednesday: Mainly VFR. N winds G15-20kt.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Conditions remain sub-SCA through Sunday with the exception of the
eastern ocean reaching about 5 feet for around 6 hours late Saturday
into early Sunday. Based on collaboration with BOX, no SCA has
been issued at this time. However. if the forecast holds one may
issue one with the next main forecast package.
SCA wind gusts are likely on the ocean Sunday night and then all
waters on Monday. Ocean seas will also build to 5-6 ft during this
time frame, likely not subsiding below 5 ft until early Tuesday
morning. Lingering SCA wind gusts are possible on the ocean Monday
night as well. Sub-SCA conditions are then expected Tuesday through
Wednesday with potential of SCA gusts Wednesday night.
&&
.HYDROLOGY...
No hydrologic concerns are expected through Saturday.
0.5-1" is expected Saturday night into Sunday night. There are
no hydrologic concerns given this is a relatively long duration
event.
No hydrologic impacts are expected next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...BR/DS
NEAR TERM...JMC
SHORT TERM...BR
LONG TERM...DS
AVIATION...JMC/JM
MARINE...BR/DS
HYDROLOGY...BR/DS