341
FXUS61 KOKX 231953
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
353 PM EDT Fri May 23 2025
.SYNOPSIS...
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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.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
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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
early this evening. Some light rain will accompany the trough,
mainly over the Lower Hudson Valley and Southern Connecticut.
Immediately behind the shortwave will be some partial clearing,
especially close to the coast and NYC metro. The brief sun and
heating should lead to weak instability between 5-10kft. This
instability may be 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 midnight with skies
remaining partly 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/...
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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.-- End Changed Discussion --
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
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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.-- End Changed Discussion --
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
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Low pressure will continue to slowly track off the eastern New
England coast, while another weak low over the eastern Great
Lakes tracks east across New England.
VFR at all but KSWF/KISP/KGON as of 1930Z. There is potential for
iso/sct showers through this evening. VFR conditions expected
tonight and into Saturday.
W winds increasing to 10-15 kt gusting to 15-20kt this afternoon,
particularly western terminals, diminish to 10 kt or less overnight.
Gusts then pick up again daytime Sat to 20-25kt.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled AMD expected.
.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
Saturday: VFR. W winds 15G20-25kt.
Sunday: MVFR. NW winds 10-15G20kt.
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...
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Main change to SCA headline on the ocean is to extend through
6 pm Saturday. Have also added 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.-- End Changed Discussion --
&&
.HYDROLOGY...
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No hydrologic impacts expected through next week.-- End Changed Discussion --
&&
.TIDES/COASTAL FLOODING...
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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 OKX surf zone forecast season begins today with a high
rip current risk for all the ocean beaches. Various
contributing factors include a 4-ft/9-sec E swell and an
opposing WSW 10-15 flow in the afternoon leading to chaotic
conditions. Surf temps have cooled off to the lower/mid 50s,
which should keep most people out of the water anyway.
The rip current risk for Saturday should be moderate as onshore
seas gradually subside.
Outlook for the rest of the Memorial Day weekend: Rip risk
likely reduces to low for Sunday, and a low risk for Memorial
Day, as onshore swells continue to subside.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...None.
NY...High Risk for Rip Currents until 9 PM EDT this 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 from 8 PM this evening to 6 PM EDT
Saturday for ANZ350-353-355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JM/DS
NEAR TERM...DS
SHORT TERM...DS
LONG TERM...JM
AVIATION...20/BG
MARINE...JM/DS
HYDROLOGY...JM/DS
TIDES/COASTAL FLOODING...