819
FXUS61 KOKX 272109
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
509 PM EDT Fri Sep 27 2024
.SYNOPSIS...
A complex frontal system slowly approaches from the southwest
tonight and then become nearly stationary. The stationary front
will remain just south of the area as high pressure builds in
from the north on Saturday and lingers through Monday. Low
pressure passes to the south Tuesday into Wednesday, followed by
a frontal passage Wednesday night. High pressure returns to end
the week.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
-- Changed Discussion --
Forecast on track with minor adjustments to slow timing of
higher PoPs this evening.
The area remains between two closed upper lows, one
moving through the Canadian Maritimes, and the other over the
Ohio Valley. A nearly stationary surface front remains across
southeastern Pennsylvania into southern New Jersey and into the
Atlantic. Meanwhile, surface high pressure remains over the
northeast. The area remains in a deformation zone and with the
slow approach of the southwestern upper low rain chances will be
increasing from the southwest through tonight. There is some
uncertainty with the movement of this low. With upper ridging
building to the north, the movement of the low will be hampered.-- End Changed Discussion --
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
With building upper riding moving into the region Saturday and
Saturday night, and surface high remaining to the northeast, the
frontal system, and closed upper low, to the southwest will be
slow to move. Will keep chance probabilities across the
southwestern areas Saturday into early Saturday evening, then
with the building upper ridge, will lower probabilities into
Saturday night. Meanwhile the northeastern areas will likely
remain dry Saturday into Saturday night.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
There still remains quite a bit of run-to-run inconsistencies among
the deterministic and ensembles for early to middle of next week,
mainly with a low pressure that passes near or south of Long Island.
Have continued to stay close to the consensus forecast using the
latest NBM.
The region will lie between two upper level lows this weekend, one
across the Tennessee and Ohio Valleys and one near the Canadian
Maritimes. Ridging will lie over the northeast between the two lows.
The upper low to our west will slowly weaken and slide east towards
the Middle Atlantic coast early next week with the second low moving
further offshore. The model differences increase greatly with how
quickly the upper low to our west opens up and slides east.
There are also differences with the handling of the surface and
upper ridging over New England, especially Monday an Tuesday. These
differences have led to a low confidence forecast regarding
potential for showers sometime Tuesday into Wednesday.
One plausible scenario where the ridging is weaker, allowing the low
and associated precipitation to push further north across our area.
Another plausible scenario is for the low to stay south of Long
Island, with ridging strong enough over the area allowing the bulk
of the showers to remain south. Given the aforementioned
uncertainty, maintained chance PoPs late Monday night into
Wednesday. Otherwise, mainly dry conditions are expected Sunday into
much of Monday, but it will likely remain mostly cloudy through
Wednesday.
The guidance has been signaling a larger, progressive upper level
trough and associated cold front passage late Wednesday into
Wednesday night. This system will help push the surface low east
lead to a much drier atmosphere to end the week Thursday and Friday
with the return of high pressure.
Temperatures will largely be near normal through the period with
highs in the upper 60s to around 70. There is a chance for a bit
more sunshine on Monday, especially inland, which could lead to
temperatures in the middle 70s in a few spots.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
The region remains between high pressure to the north and a
slowly approaching frontal boundary to the south.
VFR initially, then MVFR tonight into Saturday. There will be an
increasing chance of rain tonight into Saturday. The MVFR will
be mainly due to ceilings. Rain probably occasional tonight into
Saturday. The relatively highest chances of rain will be near and
southwest of NYC terminals.
Winds will be easterly through the TAF period near 10 kts or
less. Easterly winds increase Saturday along the coast to 10-15
kt with gusts up to near 20 kt with winds staying closer to 10
kt farther inland.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of MVFR could be a few hours off from TAF. There very
well could be some fluctuation between VFR and MVFR tonight into
Saturday.
Timing of rain could be several hours off from TAF.
Low chance of IFR Saturday.
OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
Saturday: Mainly MVFR with occasional rain mainly near and southwest
of NYC terminals. Possible IFR at times. Easterly wind gusts near 15
- 20 kt, mainly along the coast.
Sunday: Slight chance of MVFR in showers. Otherwise, mainly
VFR.
Monday: Mainly VFR. Increasing chance of showers and MVFR Monday
afternoon into Monday night.
Tuesday: MVFR/IFR with a chance of showers. Easterly wind gusts
15-20 kt day into evening.
Wednesday: MVFR/IFR with a chance of showers. Afternoon
northerly wind gusts 15-20 kt.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Winds and seas remain below advisory levels through tonight
across all the forecast waters.
The during Saturday, as a complex frontal system slowly
approaches from the southwest, wind gusts and seas over the
ocean waters will be increasing through the day. Conditions are
expected to reach SCA levels on the ocean waters west of Fire
Island Inlet early Saturday morning, and then into the central
ocean zones, and finally reaching into the ocean waters east of
Moriches Inlet by late Saturday afternoon. There is some
uncertainty that SCA conditions will develop east of Moriches
Inlet, and may be more for seas, as this will be dependent on
the timing of the frontal system moving northeast. Small craft
advisory conditions are then expected to remain on the ocean
waters through Saturday night. For the non ocean waters winds
and seas remain below advisory levels Saturday and Saturday
night.
Winds should largely remain below SCA levels Sunday through
Wednesday. Seas around 5 ft are possible Sunday, but should be
subsiding into early next week. There is a chance for seas to
build back to 5-6 ft Tuesday with a low pressure near Long
Island and may remain near 5 ft on Wednesday ahead of a frontal
passage.
&&
.HYDROLOGY...
There are no hydrologic concerns through the middle of next
week.
&&
.TIDES/COASTAL FLOODING...
There is a moderate rip current risk into this evening. The risk
increases to high on Saturday due to stronger E flow 15-20 kt
and 4-5 ft seas. The rip current risk should be moderate on
Sunday with weaker winds and seas around 4 ft.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents from Saturday morning through Saturday
evening for NYZ075-080-081-178-179.
NJ...None.
MARINE...Small Craft Advisory from 5 PM Saturday to 6 AM EDT Sunday for
ANZ350.
Small Craft Advisory from 8 AM Saturday to 6 AM EDT Sunday for
ANZ353-355.
&&
$$
SYNOPSIS...DS/MET
NEAR TERM...DS/MET
SHORT TERM...MET
LONG TERM...DS
AVIATION...JM
MARINE...DS/MET
HYDROLOGY...DS/MET
TIDES/COASTAL FLOODING...