000
FXUS61 KOKX 012013
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
313 PM EST Fri Dec 1 2023
.SYNOPSIS...
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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. 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.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
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A line of light rain has almost pushed through the area due to
enhanced lift from a jet streak. Rain will become likely generally
west to east this evening following this initial line of precip 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. Due to light/weak winds expected overnight and into the
morning, patchy fog or areas of fog may develop during this
timeframe generally caused by the airmass in place with cloud cover
remaining.-- End Changed Discussion --
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/...
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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.-- End Changed Discussion --
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
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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.-- End Changed Discussion --
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
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Offshore high pressure gives way to a wave of low pressure
moving near the local area tonight into early Saturday.
Rain while intermittent at first through the early evening, will
become more continuous into mid and late evening. Rain tapers off
overnight into early Saturday morning. Fog is expected to develop
overnight into Saturday morning, and then fog is expected to
dissipate.
VFR expected to lower to MVFR into early this evening, followed by
IFR for the late evening and overnight, and into Saturday morning.
Some localized sub-IFR is forecast outside of NYC terminals.
Improvement back to MVFR and eventually VFR expected during
the day Saturday.
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 18Z SATURDAY THROUGH WEDNESDAY...
Saturday: Mainly VFR. Possible MVFR.
Saturday night: Rain likely with MVFR to 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...
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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. No SCA has been issued yet, but if the forecast
holds, 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.-- End Changed Discussion --
&&
.HYDROLOGY...
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Around 0.25" of rain is expected Friday evening/night. THere are no
hydrologic concerns with this.
0.5-1" is expected overnight Saturday
into Sunday night. Given totals remaining away from flash flood
guidance, there are no hydrologic concerns with this system.
No hydrologic impacts are expected next week.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...BR/DS
NEAR TERM...BR
SHORT TERM...BR
LONG TERM...DS
AVIATION...JM
MARINE...BR/DS
HYDROLOGY...BR/DS