296
FXUS61 KOKX 240301
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1101 PM EDT Fri May 23 2025
.SYNOPSIS...
Low pressure over New England will slowly track into the
Canadian Maritimes through Saturday, then stall and gradually
weaken through Sunday. Weak high pressure will build into the
region on Monday and Tuesday. By midweek, high pressure moves
offshore into the Atlantic with another low pressure system
approaching from the west. Low pressure remains near the area
mid to late next week.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
-- Changed Discussion --
The forecast is on track with only minor changes needed.
Although showers continue to move through, they are expected to
diminish over the next hour or so, with dry conditions across
the entire forecast area expected just after midnight or
thereafter.
Anomalous upper low remains over the northeast through the
start of the weekend. The associated surface low will only
slowly track towards the Canadian Maritimes tonight. A shortwave
within the upper low will continue sliding across the area into
this evening. Some rain showers will accompany the trough,
mainly over thew western half of the forecast region, including
parts of the Lower Hudson Valley, Southwest CT, Northeast NJ,
NYC, and Western Long Island.
There is some weak low level instability, enough to develop
some low topped convection into the evening with freezing levels
around 5-6 kft. Any lightning will be very isolated at worst
since the instability is very shallow. The HRRR has been very
consistent with the shallow convective development early this
evening across NE NJ before shifting over the NYC metro and
western Long Island through sunset. Loss of heating after sunset
should weaken the already shallow convection, but a few
lingering showers are possible since there will continue to be
spokes of energy rotating around the larger upper low. Across CT
shower activity may be isolated this evening since there may be
some subsidence behind the aforementioned shortwave.
Any isolated showers should end by around midnight with skies
remaining mostly cloudy. Low temperatures will be cool and
continue below normal in the lower to middle 40s inland and
upper 50s and low 50s near the coast.-- End Changed Discussion --
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/...
The upper low and associated surface low continue tracking
to the Canadian Maritimes through Saturday. Several pieces of
energy/shortwaves will likely rotate around the upper low.
Cyclonic flow aloft will be maintained which will again yield
mostly cloudy skies by afternoon. The shortwaves, cyclonic flow,
and cold pocket aloft will also support potential for isolated
to scattered showers, mainly in the afternoon and evening. There
once again is weak instability 5-10kft in forecast soundings,
but appears to shallow for thunder potential. Have gone slightly
above NBM PoPs to include chance probabilities inland with
slight chance closer to the coast. Temperatures are likely to
moderate a bit more compared to recent days with readings in the
lower and middle 60s, still around 5 to 10 degrees below normal
for this time of year. There will also be a steeper pressure
gradient and deeper mixing on Saturday, supporting wind gusts
20-30 mph, strongest near the coast. Any shower could promote a
stronger gust with a drier subcloud layer.
Isolated-scattered showers should end after sunset with loss
of heating and instability. Skies will become mostly clear with
temperatures falling into the 40s inland and lower 50s closer
to the coast.
Low pressure will still spin over the Maritimes as it slowly
weakens on Sunday. High pressure gradually builds towards the
region. There will still be shortwaves and pieces of energy
moving around the upper low. There will also continue to be
afternoon stratocu which could create mostly cloudy conditions
at times. Have introduced a slight chance PoP N and W of the NYC
metro into southern CT for as an isolated shower cannot be
ruled out. Temperatures continue to moderate with highs in the
middle to upper 60s with some low 70s possible in NE NJ.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Upper level trough pattern remains Sunday night through Monday
with a strong shortwave passing south of the region. Less
positive vorticity advection is apparent behind this shortwave
in the forecast models.
Upper levels transition to more of a ridging pattern thereafter
through the middle of next week. Model differences arise in the
magnitude of ridging and how fast it weakens.
At the surface, low pressure is forecast to shift farther east
of Nova Scotia and Newfoundland Sunday night. High pressure
builds in from the Great Lakes as this low departs farther away
through Monday. The center of high pressure gets within close
proximity to the local area Monday night through Tuesday. The
high pressure area moves offshore towards Tuesday night and
continues to move farther offshore out into the Atlantic
Wednesday.
Dry conditions are expected to prevail Sunday night through
early next week. Temperatures are forecast to rebound closer to
normal values. Daytime highs will be reaching more into the 70s
for more areas comparing Memorial Day to Tuesday.
For the middle to late portion of next week, another low pressure
area will be approaching. Aloft, the ridge weakens with strong
cutoff low approaching the Great Lakes. This will invoke a
troughing pattern aloft to return to the local region. At the
surface, multiple areas of low pressure approach, one from the
Great Lakes and one from the mid-Atlantic. Both appear to be
rather weak in magnitude. Thursday night into Friday next week
appear to have more southerly synoptic flow develop and increase
with a tightening of the height gradient. There are still model
differences here with timing differences of rainfall and low
pressure areas.
Rain returns to the forecast Tuesday night through Friday.
Slight chances of rain showers Tuesday night increases to a
chance of rain showers Wednesday through Friday of next week.
Dewpoints gradually reach more into the 50s mid to late week.
Air will start to feel more humid. Despite the chances for rain
showers, daytime temperatures trend from near normal Wednesday
to above normal Thursday and Friday of next week.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
Low pressure will continue to slowly track off the eastern New
England coast then meander over northern New England through
Saturday afternoon.
VFR at most terminals. An isolated shower may still move through
terminals through around midnight or thereafter, but shower
activity is expected to diminish through the night. KSWF
Light WSW to SW winds are expected to shift more to the W after
by midnight. Thereafter, winds should turn more to the W and
continue to be light overnight before increasing after
midnight. W winds continue for Saturday at around 15 kt to 20
kt, with gusts of 20 to 25 kt by mid to late morning.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled amendments expected.
.OUTLOOK FOR 00Z SUNDAY THROUGH WEDNESDAY...
Saturday night: VFR. W winds 5-10 kt.
Sunday: MVFR. NW winds 10-15G20 kt.
Monday: VFR. NW winds 10-15 kt.
Tuesday: VFR.
Wednesday: Chance of showers with possible MVFR cond.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
SCA on the ocean remains in effect through 6 pm Saturday. SCA
still also includes the NY Harbor and LI South Shore Bays for
Saturday as wind gusts will likely end up near 25 kt late
morning into the afternoon. Seas should start to build back to
near 5 ft tonight and then winds increase late tonight through
Saturday morning with gusts 25 kt expected. Winds and seas
should subside Saturday evening. Conditions on the LI Sound and
eastern LI Bays should remain below SCA levels through Saturday
evening. All waters should then end up below SCA Saturday night
through Sunday.
Pressure gradient remains relatively weak Sunday night through
the middle of next week, keeping below SCA conditions on the
forecast waters.
&&
.HYDROLOGY...
No hydrologic impacts expected through next week.
&&
.TIDES/COASTAL FLOODING...
Water levels could touch or fall just short of minor
coastal flooding benchmarks with this evening high tide cycle
for southern portions of Nassau County and SW CT. No statement
has been issued.
Farther down the road, there is potential for localized
minor coastal flooding Sun into early next week with approach
of the new moon, causing areas to need as little as 1/4 ft of
tidal departure for minor coastal flooding.
The high risk of rip currents at the ocean beaches has been extended
through Saturday and into Saturday evening due to expectation
of there being high seas up to 5 ft within the ocean zones on
Saturday. In addition, the 2 main swell components are at large
angles with one another. The larger one is oriented from the
west and the smaller one is oriented from the east. From model
rip current probability, the highest chances are in the late
morning into early afternoon timeframe.
Outlook for the rest of the Memorial Day weekend:
The rip current risk for Sunday should be moderate as onshore
seas gradually subside.
Rip current risk likely reduces to low for Memorial Day, as
onshore swells continue to subside.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents through Saturday evening for NYZ075-080-
081-178-179.
NJ...None.
MARINE...Small Craft Advisory from 6 AM to 6 PM EDT Saturday for ANZ338-
345.
Small Craft Advisory until 6 PM EDT Saturday for ANZ350-353-
355.
&&
$$
SYNOPSIS...JM/DS
NEAR TERM...JM/JP/DS
SHORT TERM...DS
LONG TERM...JM
AVIATION...20
MARINE...JM/DS
HYDROLOGY...JM/DS
TIDES/COASTAL FLOODING...