649
FXUS61 KOKX 211141
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
741 AM EDT Wed May 21 2025
.SYNOPSIS...
A complex frontal boundary approaches today, with coastal low
pressure developing late tonight into Thursday morning. The low
moves north of the area Thursday night and tracks along the New
England coast Friday and Friday night, and into the Canadian
Maritimes Saturday. Weak high pressure returns for Sunday into
early next week, as a low passes to the south.
&&
.NEAR TERM /THROUGH TONIGHT/...
Dry conditions attempt to hold for at least a portion of the area,
especially further east this morning as the mid to upper level ridge
axis eventually pivots through. It will thus take awhile to overcome
mid level dry air. The mid level dry air is quite evident on BUFKIT
forecast soundings among the various model camps. The NAM3km and
the FV3 are in the camp that the mid level dry air gets overcome
faster, compared to the HRRR and RGEM camp which has the mid level
dry air holding in a bit longer. Either way some light rain activity
should get into western portions of the area by mid to late morning,
with eastern areas possibly as early as later in the afternoon or
perhaps as late as the early evening as far as the more organized
rain activity. In any event, it will be an overcast day with the
more unsettled weather in terms of light rain being more evident
further west. An easterly flow increases today, and will be more
noticeable this afternoon. Look for below average temperatures today
with temperatures not getting out of the 50s.
Tonight synoptic scale forcing increases with positive vorticity
advection increasing through the night and peaking into early Thu
morning. Simultaneously the best warm air advection takes shape from
0z to about 12z Thu. The LLJ gets to 30-40 kt out of the SE and E,
and thus the steadiest rain takes shape tonight and carries into Thu
morning. Temperatures will average near to slightly below normal
tonight despite moisture and cloud cover due to a cool strong
onshore flow. Winds will gust 20 to 25 mph in many locations,
with coastal sections gusting to around 30 mph at times.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
The 700 mb lobe of low pressure / shortwave pivot through slowly
during Thu morning. Carlson conveyor belt brings in the moisture off
the Atlantic with rain through the morning and into the early
afternoon. But by later in the day the 700 mb low consolidates and
starts to get further north. This likely shuts off the steady rain,
especially further south across the area with northern interior
sections perhaps holding on to steady rain for much of the day. With
the sfc reflection getting a bit further east and north the winds
are expected to get more of a northerly component and be more out of
the northeast Thu afternoon. Coastal locations once again will
see gusts close to 30 mph at times. With the cloud cover and
ENE flow regime look for temperatures once again to run below
average and not get out of the 50s region wide as rain tapers
most likely from south to north during the second half of the
day. Event rainfall totals should average 1 to 2 inches across
the region. For more details with respect to the rain and any
hydrologic response please refer to the hydrology section.
Cyclonic flow continues into Thursday night, however the best
forcing slowly pushes north of the area and into New England. Look
for periods of light shower activity with any additional rainfall to
be on the light side as the system becomes vertically stacked.
Mainly cloudy skies persist with temperatures averaging a bit below
average with lows mainly in the 40s, to around 50 in the NYC
metro.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
Key Points:
*Unsettled conditions will continue Friday with cool temperatures
and scattered showers possible.
*Temperatures start to trend warmer Saturday and especially Sunday.
Showers possible inland on Saturday.
*Chance of showers Memorial Day with temperatures near to slightly
below normal.
*Unsettled weather remains into Tuesday with a chance of showers.
An upper trough, with an enclosed low, lingers across the northeast
Friday and Saturday, and moves into Northern New England Sunday.
Another shortwave rotates into the trough Sunday night into Monday,
with unsettled weather continuing into Memorial Day. The elongated
upper trough then remains across the Great Lakes region and into the
northeast into the middle of next week. Meanwhile surface low
pressure tracks along the New England coast Friday and into the
Canadian Maritimes Saturday.
Weak surface high pressure may briefly build into the region for
Sunday into Monday. Then low pressure tracks south of the area later
Monday into Tuesday with the potential for additional rainfall.
Followed the NBM guidance through the extended period.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
Low pressure approaches from the southwest today. Another low
develops off the Carolina coast this evening and tracks
northeast tonight into Thursday.
MVFR, with brief VFR possible early at KBDR, KISP, and KGON.
Rain begins to move slowly into the terminals around 14Z west
and 16Z east, with KGON holding off possibly as late as 20Z/21Z.
Widespread IFR conditions develop late afternoon into this
evening, but there could be some pockets across the Lower
Hudson Valley this afternoon. LIFR if possible along the coast
toward Thursday morning.
E winds 10-15kt, with G15-20kt, with both the sustained winds
and gusts increasing a few kts this afternoon. Winds gradually
back to the NE late tonight.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of the rain may vary by 1-2 hours. Pockets of IFR
possible late this afternoon into the evening before becoming
IFR.
.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
Thursday: IFR, possibly LIFR, with periods of rain. E wind
gusts 20-305kt, highest east of the NYC terminals. Winds
gradually diminishing and backing to the N/NE Thursday
afternoon/night.
Friday: MVFR or lower with a chance of showers.
Saturday: Mainly VFR. A slight chance of showers inland with MVFR.
Sunday: VFR.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Small craft conditions develop today on the ocean waters as gusts
get to 25 kt for the most part and ocean seas get closer to 5 ft
late in the day. During this evening small craft conditions develop
on the near shore waters mainly from west to east. Gale watches
continue late tonight into a portion of the day on Thursday for the
ocean waters, and have added the eastern nearshore waters to the
Gale Watch through the day Thursday. During Thursday night sub
advisory conditions return from west to east on the near shore
waters as the winds turn more NW and gradually diminish into
early Friday morning. Small craft seas linger on the ocean
waters throughout Thursday night.
Small craft conditions will be possible on the ocean waters Friday
morning, with seas falling below advisory levels by the
afternoon as a northwest flow backs to the west. Winds and seas
will then remain below advisory levels across the forecast
waters through Monday night.
&&
.HYDROLOGY...
No hydrologic impacts are anticipated with the coastal system for
mid week. Flooding overall is not a concern as max rainfall rates
should stay below a half inch per hour. The rain is expected to fall
over a long enough duration to preclude flood impacts. Some minor
nuisance urban related flooding cannot be completely ruled out, but
overall impacts should be low to none. There are no hydrologic
concerns Friday into early next week.
&&
.TIDES/COASTAL FLOODING...
An increasing E-NE flow develops and persists into Thursday. Later
in the day Thursday and into Thursday evening the winds take on more
of a northerly component. This could very well limit any coastal
flooding for the Thursday evening high tide cycle, and the Friday
evening high tide cycle for coastal SW CT appears to be trending
down.
At this time it appears the main high tide cycle to monitor for the
south shore bays of Queens, Nassau, and portions of the south shore
of Suffolk is Thursday evening. Tidal departures in these spots look
to be mainly 1.5 to 2 ft, and locally as high as 2.0 to 2.5 ft out
east. The latest Stevens, ETSS, ESTOFS blend yields pockets of minor
benchmarks being touched or exceeded. There is a low probability
that Staten Island and portions of NE NJ may also approach and
barely touch minor benchmarks Thursday evening. Otherwise the area
along the coast to monitor is SW CT as Bridgeport and Stamford may
touch or slightly exceed minor benchmarks for the Thursday evening
cycle, with the Friday cycle looking less likely now for SW CT.
Trends along the NW LI gauges has come down with minor benchmarks
likely not being met.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from midnight tonight to 6 AM EDT
Thursday for ANZ331-332-340.
Gale Watch from Thursday morning through Thursday afternoon
for ANZ331-332-340.
Small Craft Advisory from 6 PM this evening to 6 PM EDT
Thursday for ANZ335-345.
Small Craft Advisory from 6 PM this evening to noon EDT
Thursday for ANZ338.
Small Craft Advisory from 11 AM this morning to midnight EDT
tonight for ANZ350-353.
Gale Watch from late tonight through Thursday morning for
ANZ350-353.
Small Craft Advisory from 11 AM this morning to noon EDT
Thursday for ANZ355.
&&
$$
SYNOPSIS...JE/MET
NEAR TERM...JE
SHORT TERM...JE
LONG TERM...MET
AVIATION...MET
MARINE...JE/MET
HYDROLOGY...JE/MET
TIDES/COASTAL FLOODING...