839
FXUS61 KOKX 251733
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
133 PM EDT Fri Oct 25 2024
.SYNOPSIS...
-- Changed Discussion --
High pressure across the area gives way to an approaching cold
front tonight. The front moves through during the early morning
hours Saturday. Another large area of high pressure then builds
in through early next week. A warm front will also pass to the
north Tuesday into Tuesday night, allowing for a warming trend
to develop.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH TONIGHT/...
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Surface high pressure was over the region early this afternoon,
and will drift south and offshore by this evening ahead of a
cold front approaching from the Great Lakes. The front moves
through during the early morning hours Saturday, before daybreak
for most locations except perhaps far eastern LI/SE CT. This is
forecast to be a dry frontal passage due to little forcing and
limited moisture. The associated upper trough amplifies while
digging into the Northeast tonight. A light northerly flow this
morning become W/SW this afternoon.
While the area will be under warm advection today as the upper
ridge axis passes to the east, a subsidence inversion will
limit the depth of the mixed layer. This will be the coolest day
of the week. Highs today are forecast to be in the lower to mid
60s, which is slightly above normal.-- End Changed Discussion --
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
On the heels of an early morning cold frontal passage Saturday,
cold advection will ensue with gusty NW winds. Gusts up to 30
mph will be possible from late morning into the afternoon.
Leaned toward the NBM 90th percentile for winds based on 00Z
model soundings from the GFS, NAM, and RAP, which all point
toward a stronger vertical wind profile. This will also elevate
the spread of wildfires. See Fire Weather section below.
Highs on Saturday with deeper mixing will actually be warmer
than Friday, but still in the 60s and several degrees above
normal. Cold advection will continue into Saturday night with
overnight lows actually a few degrees below normal. Readings
Sunday morning will range form the mid and upper 30s inland and
the Pine Barrens Region of LI, to the lower and mid 40s elsewhere.
Winds will gradually diminish through the night and any frost looks
to be patchy across the interior. Sunday will be much cooler with
highs in the 50s. Based on model 2m temps and a trend toward
cooler, undercut NBM slightly. This is also close to MET/MAV
MOS. NW winds will be considerably weaker than Saturday.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Dry weather is expected in the extended as high pres drifts
offshore and an upr ridge builds over the East Coast again. This
pattern will also allow for a warming trend thru the period.
Based on model agreement and the h85 wly wind flow, went abv the
NBM for high temps Wed and Thu. The numbers at this point may
still be too low, with mixing down the GFS producing at least
low 80s for the area. The challenge is always how much the water
influences local temps, and how deep the mixing is, especially
with a sly component to the flow. For these reasons the fcst is
warmer than the NBM, but with room for adjustment based on these
other factors. Otherwise, the NBM with only minor tweaks was
used for the rest of the extended period at this point. However,
will need to focus on Sun ngt, as temps may drop further than
the NBM suggests if winds diminish sufficiently. The MEX is
colder and may be better in this scenario.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
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High pressure weakens over the area today. A cold front passes
through early Saturday morning, with high pressure building in
thereafter.
VFR through the TAF period.
Winds become W-SW under 10 kt this afternoon with sea breezes
and synoptic flow. Light W-SW winds tonight, then winds shift
to the NW around 12Z Saturday behind the cold front. Speeds
increase during the day Saturday with gusts around 25kt
possible late morning through the afternoon. Gusts could
occasionally be a few kt higher.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of wind shift Saturday morning could be off by a few
hours as well as the start time of gusts.
Gusts could occasionally be a few kt higher than what the TAF
shows.
OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
Saturday Afternoon: VFR. NW wind gusts around 25kt.
Sunday-Monday: VFR.
Tuesday-Wednesday: VFR. S wind gusts 15-20 kt possible.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
While high pressure builds over the waters today, an ESE swell
will result in seas around 5 ft on the ocean. This could linger
into early this evening, but confidence was too low to extend
the SCA.
A cold front moves through the waters early Saturday morning
with NW gusts strengthening to 20 to 25 kt. Seas look to be
around 4 ft. Blended NWPS seas with the lower Wavewatch as
it has often been too high in offshore flow events. However, a
SCA may still be needed for Saturday, especially during the
afternoon and nighttime hours. Winds and seas will then subside
late Saturday night into Sunday with high pressure building in
from the west.
High pres will keep winds and seas blw sca lvls Mon and Tue. By
early Wed however, increasing swly flow should allow for the
development of SCA conditions on the ocean thru Thu.
&&
.FIRE WEATHER...
-- Changed Discussion --
Conditions are expected to be marginally favorable for wildfire
spread today, with min RH less than 40 percent, but winds won`t
be nearly as strong, generally 5 to 10 mph. SPS has been issued
for NE NJ and S CT per earlier collab.
Temps will be cooler this weekend into early next week, but with
min afternoon RH 25-35 percent from Sat into Mon. NW winds may
also gust to 25-30 mph Sat afternoon and early evening, with
meteorological conditions meeting red flag criteria in NE NJ
and in/just outside NYC, and close to it for the rest of area.
Winds will be considerably weaker for Sunday.-- End Changed Discussion --
&&
.HYDROLOGY...
The prolonged stretch of dry weather continues and there are no
hydrologic concerns.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ350-
353-355.
&&
$$
SYNOPSIS...JMC/DW
NEAR TERM...MET/DW
SHORT TERM...DW
LONG TERM...JMC
AVIATION...JT
MARINE...JMC/MET/DW
FIRE WEATHER...
HYDROLOGY...JMC/DW