000
FXUS61 KOKX 231720
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
120 PM EDT Tue May 23 2023
.SYNOPSIS...
High pressure will be in control through tonight. A cold front
approaching from the north Wednesday will move through the region
Wednesday night. High pressure builds in from the northwest Thursday
and settles across the area Friday. The high remains over the
region into the holiday weekend as low pressure approaches from
the south. The low moves into the area Memorial Day.
&&
.NEAR TERM /THROUGH TONIGHT/...
Only minor changes have been made to temperatures and dewpoints
to account for current obs and trends. Overall, the forecast
remains on track.
Areas of low stratus have developed over much of Long Island and
SW CT where easterly flow off the ocean has helped to saturate
the low levels. What remains of this should erode fairly quickly
later this morning with daytime heating, leading to a mix of
sun and scattered cu this afternoon. RAP continues to show an
expansive area of smoke aloft stemming from wildfires over
western Canada. 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.
High pressure centered over Atlantic Canada gradually slides east
and offshore through this evening, maintaining the onshore
flow. This will keep temperatures a bit lower than normals, with
highs in in the low-to-mid 60s along the coast and into the
lower 70s inland.
Winds lighten and with clear skies overnight should allow for
radiational cooling across interior southern CT and the LI Pine
Barrens, where temperatures may touch the upper 30s briefly.
Elsewhere, temperatures bottom out in the 40s, or lower 50s in the
urban metro. Blended in MET/MAV data for lows tonight to account
for this, otherwise, blended guidance was followed for this update.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
Sharp trough in the northern branch of the jet swings southeast from
Canada Wed through Wed night, sending a surface cold front toward
and through the region.
Ahead of the approaching boundary, the persistent onshore flow will
continue to limit daytime heating along the coast, where highs
remain in the 60s. Inland however, a mild SW flow likely allows
parts of NE NJ and the Lower Hudson Valley to achieve the upper 70s.
The front approaches from the north late in the day. With limited
moisture, not anticipating a widespread rainfall from the fropa,
though a few scattered showers potentially make it into the region
as the front sinks south, with highest chances of seeing this across
the interior. Also can`t rule out an isolated thunderstorm,
especially across the Lower Hudson Valley where model soundings
indicate some weak instability in the late afternoon. Timing of
any wet weather is early to mid evening, with drying conditions
behind the passage Wed night. Total rainfall, where it does
occur, will primarily remain under a tenth of an inch. Coastal
locations may remain entirely dry.
Conditions dry out Wednesday night behind the front, with a 1030 mb
high building in from the northwest once again. Blustery conditions
develop post-frontal into Thursday with a tightening pressure
gradient as the high builds, generally gusts 20-25 mph. Blended
in the NBM 90th percentile for winds late Wed night into Thursday
due to this possibility.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
Surface high pressure will be building toward the region from the
northwest Thursday and settle across the northeast and Great Lakes
region Friday. Breezy northwest winds will be likely especially
early. Highs Thursday will be a few degrees below seasonal normals.
The high remains over the region but weakens during the holiday
weekend as weak steering flow aloft develops.
Weak low pressure developing along the southeast coast Friday will
move slowly north into the ridge through the weekend. There is
uncertainty as to the strength of the high and how quickly the low
will move into the region. The deterministic guidance keeps the area
dry until later Monday, while ensembles bring moisture into the area
beginning late Saturday. WIth the uncertainty have leaned toward
the NBM probabilities late Saturday into the beginning of next
week.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
High pressure will remain in control through Wednesday morning.
A cold front approaches from the north Wednesday afternoon.
SE winds 10-13 kt this afternoon. Winds gradually diminish this
evening and then become light and variable overnight. Winds will
become S-SE middle to late Wednesday morning and increase into the
afternoon around 10 kt. The flow should become SW at KSWF ahead of
the approaching cold front Wednesday afternoon.
Mainly VFR. Included a PROB30 for showers Wednesday evening in the
30 hour TAFS (KJFK, KLGA, KEWR, and KSWF).
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Wind direction at KLGA may remain NE an hour longer than
forecast this afternoon.
OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
Wednesday PM: Mainly VFR. A chance of showers during the late
afternoon and early evening, mainly from NYC on NW. A slight chance
of thunder near KSWF in evening. S-SW winds shifting to N at night
and gusting 20-25 kt.
Thursday-Friday: VFR. N wind G20-25 kt Thursday morning.
Saturday-Sunday: VFR. A slight chance of showers.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Conditions will remain below SCA levels through Wednesday with high
pressure in control.
Increasing northerly winds behind a frontal passage Wednesday
evening may allow for a period of SCA criteria gusts on the ocean
and some of the non-ocean waters surrounding Long Island late
Wednesday night into Thursday morning. Ocean seas may briefly top
5 ft early Thursday.
Winds and ocean seas will be diminishing through the day Thursday as
high pressure north of the Great Lakes builds southeast and the
pressure gradient force across the forecast waters weakens. Small
craft advisory conditions will be on-going across the ocean waters
Thursday morning, then fall below during Thursday afternoon. Winds
and seas will then remain below advisory levels Thursday night
through Saturday night.
&&
.HYDROLOGY...
No hydrologic impacts expected through early next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...DR/MET
NEAR TERM...BR/DR
SHORT TERM...BR/DR
LONG TERM...MET
AVIATION...DS
MARINE...DR/MET
HYDROLOGY...DR/MET