Area Forecast Discussion
Issued by NWS Upton, NY
Issued by NWS Upton, NY
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FXUS61 KOKX 270732
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
232 AM EST Thu Nov 27 2025
.SYNOPSIS...
Strong low pressure remains north of the region with high pressure
well southwest of the region for Thanksgiving through Friday night.
By the start of the weekend, the high pressure area to the south and
west will build more into the region. The high pressure passes east
of the region early Sunday giving way to another frontal system from
the west. Associated cold front moves across Sunday night. This will
be followed by high pressure for Monday. The high departs northeast
of the area with another low approaching from the south and west
towards the middle part of next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
One area of low pressure attached to the cold front that moved
across overnight will be heading into the Canadian Maritimes and
deepening. Another area of low pressure will be in Quebec where
it will maintain nearly the same magnitude and will not move
too much in position through today.
The local region will remain a tight pressure gradient between low
pressure to the north and northeast and high pressure well to the
southwest. Dry conditions, gusty winds and colder temperatures are
expected. NBM high temperatures already below MOS and kept those
values for the high temperatures, mainly in the lower 40s. Max wind
gusts today are expected to be mostly near 35 mph with some peak
wind gusts to 40 mph. Wind chills today stay in the 30s at most.
For tonight, the winds will remain brisk and a much colder night is
expected compared to the previous night. The low in Quebec slightly
decreases in strength and moves farther east. The region remains in
a gusty westerly flow. Forecast lows due to winds staying up will
not exhibit as vast a range, ranging mainly from the upper 20s to
lower 30s with wind chills making around 10 degrees colder than the
actual temperature.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
Key Point
* Friday winds gust to 40 to 45 mph, possibly higher, close to
50 mph at times.
* Friday still very cold with high temperatures upper 30s to
lower 40s. Max wind chills mostly in the lower 30s.
The low in Quebec makes its way towards the Canadian Maritimes
without much change in strength with its central low pressure. The
pressure gradient during the day Friday between this low and high
pressure well to the southwest becomes the most tight, indicating an
even more gusty westerly flow. This will be conveyed through a
deeper mixing layer and steeper lapse rates which are shown in the
forecast model BUFKIT soundings. There is some indication also of
some narrow sliver of elevated CAPE and with positive vorticity
advection could have a few rain and/or snow showers for parts of the
region. POPs are just slight chance for this.
The core of the 850mb cold pool will be across the region so made
some adjustments to NBM to account for this. Went higher than NBM
for clouds and POPs as well as winds and lower than NBM for
temperatures. NBM 90th percentile winds were used and even with this
were manually adjusted up to better match up with forecast soundings
from BUFKIT especially with deep vertical mixing. The current
forecast has wind gust maxima of 40 to 45 mph, just below wind
advisory criteria. Cannot rule out a few wind gusts to wind advisory
thresholds, near 50 mph.
At this time, still too early and not high enough confidence to go
with wind advisory. Would like to see guidance trend a little higher
and LAMP gusts indicate some mid to upper 30s for wind gusts to
increase confidence in wind advisory for Friday. BUFKIT already
indicating a few spots mix in late afternoon into evening up to near
800mb with 45 kt at top of mixed layer. Would also want to see more
40kt wind gust potential in the HRRR fields also. Currently, this
wind gust potential is only indicating some areas of 35-40 kt wind
gust potential within the region for Friday mainly in the
easternmost part of LI Sound. Forecast high temperatures Friday are
mostly in the upper 30s to lower 40s with wind chills at most in the
lower 30s for most locations.
For Friday night and Saturday, dry conditions with a gradual
downward trend in winds are expected. This will come as high
pressure gets within closer proximity to the local region, allowing
for a relaxation of the pressure gradient. Similar lows to the
previous night are expected, mainly upper 20s to lower 30s. For high
temperatures Saturday,those will also be quite similar to the
previous day, mostly lower 40s. However, winds will be much less,
allowing for wind chills to only be mostly in the upper 30s.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Models still exhibit an active pattern, with 2 main shortwaves,
one passing to close out the weekend and another towards the
middle of next week. At the surface, one parent low with its
frontal system passes to the north of the region end of this
weekend. However, the other low pressure area towards middle of
next week will be situated lower in latitude, potentially
crossing near to south of the region with some strengthening of
the low as it moves by. Previous discussion follows with more
details.
Key Points:
* 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 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 /07Z THURSDAY THROUGH MONDAY/...
A cold front passes offshore tonight. The associated low
pressure system remains over southeastern Canada today.
VFR thru the TAF period.
Increasing W winds overnight. Gusts tonight generally around 25 kt but
isolated gusts upwards of 30-35kt possible.
W flow increases today 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...
Isolated gusts around 40kt possible thru around 7Z.
.OUTLOOK FOR 06Z FRIDAY THROUGH MONDAY...
Late Tonight: 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...
The small craft advisory remains in effect for all waters through
tonight. The gale watch was upgraded to a gale warning for all
waters on Friday. For NY Harbor the gale warning goes until 6PM but
for the rest of the waters, the gale warning goes until 12AM
Saturday. The larger areas of water, larger marine areas will have
more effective mixing and those gales are forecast longer into
Friday evening.
Overnight Friday night into early Saturday, winds are expected to
decrease further into SCA range. SCA conditions linger on the ocean
Saturday and for non-ocean waters as well. NY Harbor is forecast to
be below SCA thresholds for Saturday. Eventually by mid to late
Saturday afternoon, all waters go below SCA thresholds. All
waters are forecast to remain below SCA thresholds for Saturday
night.
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...
No hydrologic concerns through the middle of next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EST Friday for ANZ331-332-335-
338-340-345-350-353-355.
Gale Warning from 6 AM Friday to midnight EST Friday night for
ANZ331-332-335-340-345-350-353-355.
Gale Warning from 6 AM to 6 PM EST Friday for ANZ338.
&&
$$
SYNOPSIS...JM
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...BG/JM
AVIATION...JMC/MW
MARINE...BG/JM
HYDROLOGY...JM