Area Forecast Discussion
Issued by NWS Upton, NY
Issued by NWS Upton, NY
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FXUS61 KOKX 262343
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
643 PM EST Wed Nov 26 2025
.SYNOPSIS...
A cold front will move across tonight. The region will then
remain between strong low pressure to the north and high
pressure well southwest for the rest of the week. The high will
build across on Saturday, then pass east of New England
Saturday night. Low pressure moving across the upper Great Lakes
on Sunday will send a cold front across Sunday night, followed
by strengthening high pressure building across on Monday.
The high will retreat into New England Monday night into
Tuesday as low pressure approaches from the southwest. The low
will pass east on Wednesday.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Closed upper low over the Great Lakes will send a cold front
across this evening. Ahead of the front, mild conditions
continue along with low clouds and some locally dense fog along
the south shore of Long Island and SE CT. Special Weather
Statement addresses this. Fluctuations in visibilities are
likely and conditions may be better heading north of the Long
Island Expressway.
A broken band of showers will also accompany cold fropa, across
the lower Hudson Valley, NYC metro and western Long Island/CT
mainly from 7-9 PM, and eastern sections from 8-10 PM.
Isolated thunder and a brief downpour expected across NYC metro
and western Long Island with this line.
Clouds will quickly clear behind the front along with much
cooler and drier air advecting into the area, with increased
boundary layer mixing. Winds will quickly pick up out of the
west once the front passes. Gusts likely to peak just over 40
mph with fropa, and obs to the west are bearing this out with Mt
Pocono PA gusting to 37 kt during the past hour. Winds should
then diminish somewhat early in the morning, but with gusts
20-30 still possible.
Temperatures by daybreak Thanksgiving Day will range from the
mid/upper 30s, with wind chills potentially as low as the
mid/upper 20s.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
Key points:
* Brisk conditions expected on Thanksgiving Day with winds 15-20
mph gusting to 25-35 mph. Daytime temperatures reach the
lower/mid 40s, with wind chills in the 30s.
* Brisk and chilly conditions continue on Friday with potential of
stronger winds. Sustained winds 20-25 mph possible with gusts 30-
40 mph. A few gusts up to 45 mph are possible. Wind chills stay
mostly in the 20s to lower 30s.
Deep upper troughing along with a closed upper low will persist over
the eastern US through the end of the week. Surface low pressure
will reside over southeast Canada Thanksgiving morning and then
slowly lift towards the maritimes through Friday night. Strong high
pressure will remain across the Plains on Thanksgiving and then
slowly shift east on Friday. This will leave the region between
these two systems, setting up a strong pressure gradient over the
area. Model soundings are indicating modest mixing on Thanksgiving,
with a subsidence inversion between 5-10 kft. Low level winds
average around 25 kt within the boundary layer. Cold advection will
continue with the mixing allowing winds to reach 15-20 mph along
with gusts 25-35 mph, strongest near the coast. Maintained
continuity with previous forecast which continues to be around or
slightly above the 90th percentile of the NBM for wind gusts.
Scattered to broken stratocu clouds are possible, especially in
the afternoon.
Thursday night will be cold with temperatures bottoming out in the
mid 20s inland and lower 30s closer to the coast. Combining the
winds it could feel like the upper teens to low 20s at times early
Friday morning.
Friday still looks like the strongest winds although there remains
uncertainty, especially with peak gusts and timing. Models have
trended slightly weaker overall over the last 24 hours. However,
similar patterns in the last few months have resulted in stronger
wind gusts, especially compared to the NBM and even the 95th
percentile of the NBM. Previous forecasts have been going above
the 95th percentile and this still seems reasonable, especially
for Friday afternoon. Mixing is expected to be deeper, up to
6-8kft. Winds in this layer may reach 40-45 kt at times Friday
afternoon. There is always a question of how much of this mixes
to the surface. Cold advection, subsidence, and westerly flow
along with the deep mixing support potential of gusts 40-45 mph
Friday afternoon. These values are just below wind advisory, but
it is not out of the question for a wind advisory to be needed
in subsequent forecasts.
Otherwise, temperatures will likely be a few degrees colder in the
lower 40s. Several vorticity maxima within the upper trough
pass through the area. Some snow showers/flurries may reside
just NW of the area. A few flurries could push into the Lower
Hudson Valley. Winds should start to weaken Friday night as
surface high pressure starts building closer to the area.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Key Points:
* Saturday will be cold and brisk as high pressure builds from the
west.
* Sunday will feature near to slightly above normal temperatures
ahead of a cold front approaching from the west. Cold fropa should
take place Sunday night, preceded/accompanied by some showers.
* Monday should be mainly dry and becoming colder as strengthening
high pressure slides across.
* The first widespread wintry precipitation event of the season may
occur mainly from Tuesday into Tuesday night as the high retreats
into New England and low pressure approaches from the southwest,
riding a frontal boundary to the south.
NWP guidance is consistent through early next week on the idea of
vertically stacked high pressure sliding across on Sat, then an
upper trough and sfc low moving through the upper Great Lakes on
Sunday and sending a sfc cold front toward the area on Sunday. As
this upper trough moves across the Northeast Sunday night the cold
front should move through, with mid level confluence in its wake
supporting high pressure moving across from the west.
Forecast certainty of course diminishes farther out in time as flow
aloft becomes WSW aloft and a srn stream upper trough moves across
the Plains states on Tue and then toward the Mid atlantic Coast on
Wed. Forecast follows the NBM and keeps precip character light at
best for Mon night should any even occur during that time frame.
Better chances for precip attm appear to be Tue into Tue night as
better forcing with the approaching sfc low approaches, with precip
mostly rain for NYC and coastal sections, and either snow or a
rain/snow mix inland. As the low passes by and temps cool off Tue
night into Wed AM, precip could go over to all snow inland and
rain/snow for NYC/coastal sections. However, usual questions re
phasing of srn/nrn streams and and ridging off the Southeast coast
that could influence low track, and strength of mid level confluence
with the polar jet and sfc high pressure to our northeast for supply
of cold air, all come into play. In particular, the polar jet to the
northeast could be modeled as too strong and the ridge off the SE
coast too weak, both of which could lead to a low track slower to
the area and a warmer solution overall. Meanwhile a less phased
solution could lead to a low track farther south and a somewhat
colder scenario. Because of these uncertainties the forecast trend
will be more important than the actual details until we get into
closer range.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
A cold front continues to approach from the west with passage
expected this evening into late tonight. The associated low
pressure system remains over southeastern Canada through
Thanksgiving Day.
IFR and lower this eve ahead of the cdfnt. Some arpts may hit
minimums at times due to fog. Shwrs and isold tstms with the
front. Included tempos for tstms NYC terminals, with shra
elsewhere. ISP may need to be amended to include tsra depending
on how well they hold together.
Becoming VFR behind the fropa and remaining VFR thru the
remainder of the TAF period.
S/SW flow 10 kt or less ahead of the front this evening. Winds
shift to the W and become gusty once again late evening and
through tonight behind the frontal passage. Gusts tonight around
25 kt possible. W flow increases Thanksgiving Day 15 to 20 kt,
with gusts mainly 25 to 30 kt, and briefly higher along the
coast late morning into the afternoon. Winds and gusts begin to
diminish toward sunset.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Any tstms are expected to be isold attm. Shwrs can be expected
however. There is a chance that IFR or lower fog gets into LGA
before 2Z.
.OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY...
Thursday Night: VFR with W winds 15-25kt.
Friday: VFR. W flow 15-25 kt with gusts 30-40 kt.
Saturday: VFR. NW flow with gusts 15-20 kt.
Sunday: VFR in the morning then MVFR or lower with rain during the
afternoon and at night. S flow with gusts 15-20 kt.
Monday: VFR. Slight chance of showers in the morning.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Marine Dense fog advy expanded to include all ocean waters as
well as continuing on the eastern Sound and the bays of Long
Island. The advisory has also been extended until 9-10 PM until
W winds following cold fropa scour the fog out quickly.
The passage of the cold front passes tonight allows winds to
increase on all waters. SCA gusts 25-30 kt are expected through
Thursday night. A few gale force gusts are likely late tonight
after the frontal passage.
SCA gusts and seas will continue Thursday night. No longer
anticipating gale potential Thursday night so have converted
the watch to an SCA. Winds will then increase on Friday with
widespread gales possible. Based on collaboration with
neighboring offices, have maintained the gale watch for now on
all waters. Winds should fall back to SCA levels on Friday
night.
Ocean seas 6-9 ft are expected by Thursday, persisting through
Friday. Seas each of Moriches Inlet could build close to 10 ft
by Friday. Waves on Long Island Sound look to range between 4
to 7 ft, especially Thursday night through Friday.
Lingering SCA cond on the ocean Sat AM should subside by
afternoon as high pressure builds across. Increasing S flow
ahead of a cold front Sunday into Sunday evening could bring a
return of SCA cond to the ocean, far ern Long Island Sound and
the Long Island south shore/ern bays, with gusts 25-30 kt and
ocean seas building to 5-7 ft. Winds diminish after cold fropa
Sunday night, with lingering 5-ft seas on the ocean after
midnight, then quiet cond on all waters by early Mon morning as
high pressure returns.
&&
.HYDROLOGY...
There are no hydrologic concerns through middle of next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Dense Fog Advisory until 11 PM EST this evening for ANZ331-332-
340-345-350-353.
Small Craft Advisory until 6 AM EST Friday for ANZ331-332-335-
338-340-345.
Gale Watch from Friday morning through Friday afternoon for
ANZ331-332-335-338-340-345-350-353-355.
Small Craft Advisory until 6 AM EST Friday for ANZ350-353-355.
Dense Fog Advisory until 9 PM EST this evening for ANZ355.
&&
$$
SYNOPSIS...BG/DS
NEAR TERM...BG/DS
SHORT TERM...DS
LONG TERM...BG
AVIATION...JMC/MET
MARINE...BG/DS
HYDROLOGY...BG/DS