234
FXUS61 KOKX 102342
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
742 PM EDT Tue Sep 10 2024
.SYNOPSIS...
High pressure will strengthen across the local region tonight
into Wednesday. High pressure will remain in control thereafter
through next Tuesday.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
-- Changed Discussion --
Updated for current conditions. Lowered cloud cover through
tonight with mainly clear skies expected.
Dry conditions expected with high pressure in control.
Nearly steady trend in the 500mb height tendency. Models are
indicating some weak positive vorticity advection moving across
tonight. This will present as an increase in clouds in the
upper levels. However, on the larger scale the pattern indicates
some confluence across the local area, which should strengthen
surface high pressure. This will allow for more subsidence.
Only expecting the sky to trend from mostly clear to partly
cloudy and still think there will be nearly optimal radiational
cooling. Surface winds will become very light.
Preferred the MAV guidance for min temperatures tonight. This
guidance depicts a larger spatial difference between
temperatures with cooler temperatures for rural, outlying, and
valley areas. Nearly optimal radiational cooling is expected
tonight so anticipating spatial differences of near 20 degrees
between these cooler outlying locations (lower 40s) and some
locations within NYC (lower 60s).
For parts of the Pine Barrens and the Lower Hudson Valley as well as
interior SW Connecticut, some patchy fog is forecast to develop late
tonight into early Wednesday morning. This will be a radiational fog
and was placed in the forecast where there is forecast to be
saturation as temperatures lower to the dewpoint. Within these
areas, the fog likely favor development along the river valleys. The
NAM indicated this possibility more than other models such as the
HRRR.-- End Changed Discussion --
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
Dry conditions remain Wednesday through Thursday with high
pressure remaining in control.
Mid levels from Wednesday through Thursday exhibit an overall
ridging trend with rising heights. At the surface, high
pressure across the region Wednesday will eventually shift
offshore Wednesday afternoon into Wednesday night, where it will
continue to build. The high pressure will continue building
offshore on Thursday.
Winds will gradually shift from calm across the interior and
light northerly flow along the coast to more of a SE flow
across the entire region Wednesday and Thursday. Winds are
expected to diminish once again Wednesday night.
For max temperatures forecast on Wednesday, used a blend of
MAV and MET guidance along with the NBM 50th percentile. This
blend keeps coastal locations relatively cooler.
For Wednesday night, another optimal night of radiational
cooling is expected. Again favored the MAV guidance for min
temperatures with their display of more vast temperature
differences between outlying and urban temperatures. This
guidance indicates lows in the upper 40s for outlying, rural,
and valley locations and low to mid 60s within NYC.
With warmer temperatures present at 850mb compared to the
previous night, this will present an inversion within the
soundings in the region. With the more SE low level winds and
the diminishing of these winds, there will be more low level
moisture to work with. As a result, there is a larger part of
the region forecast to have patchy fog develop, but again mostly
across the interior and within the Pine Barrens where low level
saturation is forecast as temperatures lower to the dewpoint.
For Thursday, 850mb temperatures trend slightly warmer than
the prior day. Despite low level SE flow, still think
temperatures will trend warmer. Used the NBM for max temperature
forecast which conveyed warmest temperatures across the
interior and NE NJ. These locations will have the least marine
influence with the low level winds and thereby should mix more
vertically during the afternoon compared to locations to the
east.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
The period will feature an extended period of warm and dry weather
as a nearly full amplitude ridge remains from eastern Canada into
the southeast. Meanwhile high pressure remains near stationary over
northern New England to off the New England coast. The high may
weaken going into Monday night and Tuesday as low pressure
potentially develops off the southeastern coast and tracks north.
Low temperatures will be near normal through the period while daytime
high temperatures will be up to 5 degrees above normal Friday
through Sunday, and close to normal Monday and Tuesday with more of
an easterly flow becoming established. There is the chance for
valley fog and radiational fog each night Thursday night, through
Monday night. And, at this time have only included in the weather
grids Thursday night through Saturday night.
The NBM was followed through the extended period.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
VFR as high pressure builds in.
N-NE winds tonight under 10 kt, late this evening/overnight.
Outlying terminals will likely go light and variable.
S/SE sea breezes are expected on Wednesday. Any locations that don`t
see a sea breeze will eventually become S/SE later in the afternoon
with the synoptic flow. Wind speeds will generally be under 10
kt.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled amendments expected through tonight. Some
uncertainty in wind direction and timing of sea breeze for
Wednesday.
OUTLOOK FOR 00Z THURSDAY THROUGH SATURDAY...
Mainly VFR. Some late night/early morning low clouds/patchy fog may
be possible at terminals outside of NYC Wednesday through
Saturday night.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
-- Changed Discussion --
No changes at this time.
Conditions on the forecast waters remain well below SCA
thresholds with high pressure staying in control for the short
term period through Thursday.
With high pressure remaining in control winds and seas remain
below advisory levels Thursday night through Monday.-- End Changed Discussion --
&&
.HYDROLOGY...
No hydrologic impacts are expected through next Tuesday with
high pressure in control.
&&
.TIDES/COASTAL FLOODING...
There is a low rip current risk at the ocean beaches through
Thursday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JM/MET
NEAR TERM...JM/MET
SHORT TERM...JM
LONG TERM...MET
AVIATION...JP
MARINE...JM/MET
HYDROLOGY...JM/MET
TIDES/COASTAL FLOODING...