000
FXUS61 KOKX 241706
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
106 PM EDT Wed May 24 2023
.SYNOPSIS...
A cold front approaches from the north today, moving through
this evening. High pressure then builds over the region Friday
and remains Saturday. The high weakens and moves offshore Sunday
and Monday as a backdoor cold front approaches from the
northeast, and low pressure approaches from the south. High
pressure strengthens Tuesday.
&&
.NEAR TERM /THROUGH TONIGHT/...
Forecasted temperatures and winds remain on track for the near
term. Minor adjustments were made for dewpoints on Long Island
as some locations are still on the dry side.
A sharp trough in the northern branch of the jet swings
southeast from Canada, sending a surface cold front toward and
through the region into tonight.
Weak surface high pressure in place continues to shift offshore
today as the front drops south. Ahead of the approaching
boundary, persistent onshore flow will limit daytime heating
along the coast, where highs remain in the 60s. Elsewhere
however, a mild SW flow allows temperatures to climb into the
70s, with mid-to-upper 70s expected in parts of NE NJ and the
Lower Hudson Valley under plenty of sunshine.
An expansive area of smoke stemming from wildfires over western
Canada remains overhead. This may contribute to a hazier than
typical look to the sky, and perhaps add a bit of color to the
sunrise/set, with little additional impact.
By late afternoon or early evening, a fairly uniform line of
showers along the advancing cold front is expected to enter
northern portions of the Lower Hudson Valley. BUFKIT soundings
indicate MUCAPE values as high as 500 J/kg up in this area,
which may allow for a few embedded thunderstorms in the line and
produce a quick downpour. The line should largely dissipate
though as it progresses south and east and runs into a much more
stable air mass along the coast. It`s possible some coastal
areas remain entirely dry. Hi-res short-term guidance, including
the 00z HREF, have nudged rainfall amounts up a tad, generally
a few tenths across Orange/Putnam, lightening to up to a tenth
elsewhere. It`s possible some parts of Long Island and SW CT
remain entirely dry.
Conditions dry out tonight as increasing northerly winds behind
the front advect in a cooler, drier air mass. Largely followed
blended guidance in this period, though blended in NBM 90th
percentile to bump up winds behind the fropa.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
Into Thursday, the trough cuts off from the jet, and the upper
low lingers over northern New England through Thursday night.
Surface high pressure gradually builds into the Great Lakes
behind the fropa, allowing for a mix of sun and clouds through
the day.
Blustery conditions persist though through the morning hours with
the tightened pressure gradient, with occasional gusts topping
20-25 mph. This should lighten as the gradient relaxes by the
afternoon hours.
Temperatures will be relatively cool for late May, with highs in
the 60s regionwide, or around 5 degrees below historical averages.
Maintained a bit cooler forecast than the national blend given
what appears to be another ideal night for efficient radiative
cooling outside the urban metro. Otherwise, blended guidance was
followed for this update.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
High pressure will dominate through most of the extended period,
with a backdoor cold front approaching Sunday into Monday, and then
moving back north as a warm front Tuesday. Meanwhile, a weak low
along the southeast coast will slowly move northward, but likely
remains to the south as upper level ridging builds to the north
Saturday and remains into the beginning of next week. The
deterministic models keep the area dry, while ensembles bring slight
chances of precipitation, mainly just along the coast, from Saturday
night into the beginning of next week. With the uncertainties with
the low and backdoor cold front followed the NBM guidance for the
extended period.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
-- Changed Discussion --
A cold front approaches from the north this afternoon and
passes through by this evening around 00z. High pressure builds
in from the northwest late tonight and Thursday.
Southerly winds around 10 kt increasing this afternoon,
possibly briefly becoming SW just before the cold front passage.
The SW flow is more likely at KSWF. Winds shift to N behind the
cold front with winds increasing into the evening and
overnight, with gusts 20-25kt possible.
VFR with a chance of showers this evening. There is a low chance
of brief MVFR ceilings with the showers, but confidence too low
to put in the TAFs. The exception is KSWF where showers are
likely, as well as MVFR ceilings. There is a chance of a
thunderstorm with briefly gusty winds.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Low chance of amendments due to brief MVFR ceilings and
showers.
Timing of wind shift with cold frontal passage may be off +/- 1-2
hours. There may be occasional northerly gusts with the showers.
OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY...
Thursday-Friday: VFR. N wind G20-25kt Thursday morning.
Saturday-Monday: VFR. A slight chance of showers on Sunday near
the coast.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
A cold front moves through the waters this evening, with
increasing northerly flow behind the passage. Gusts 25 to 30 kt
develop on the ocean waters late tonight, continuing into
Thursday morning before subsiding. Ocean seas will also
increase to around 5 ft by Thursday morning, and potentially
linger into the afternoon. Extended the SCA in place until 18z
Thu to account for this, though a further extension is possible.
On remaining waters, including the NY Harbor, Long Island
Sound, and the back bays, occasional gusts to 25 kt will be
possible late tonight into early Thursday morning. A short-fuse
SCA is not out of the question.
Otherwise, winds and seas remain below SCA levels across all
the forecast waters late Thursday through Sunday night as high
pressure dominates.
&&
.HYDROLOGY...
No hydrologic impacts expected through early next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 11 PM this evening to 2 PM EDT
Thursday for ANZ350-353-355.
&&
$$
SYNOPSIS...DR/MET
NEAR TERM...BR/DR
SHORT TERM...DR
LONG TERM...MET
AVIATION...IRD
MARINE...DR/MET
HYDROLOGY...DR/MET