000
FXUS61 KOKX 311959
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
359 PM EDT Wed May 31 2023
.SYNOPSIS...
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High pressure will remain in control but will be slightly
weakening across the local area Thursday night into early
Friday. A backdoor cold front is expected Friday night/Saturday
morning with low-pressure building through the weekend. A
coastal low will impact us Monday-Tuesday. Another cold front
is expected Tuesday into Wednesday.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
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Patchy smoke and haze across parts of the area going into this
evening. Tonight, the patchy smoke shift more towards the
interior parts of the region within NE NJ and Lower Hudson
Valley where it will linger. Smoke forecast diagnosed from near
surface smoke parameter of the HRRR.
Otherwise, mostly clear sky conditions along with decreasing
winds will allow for radiational cooling. With light onshore
flow along the coast, expecting for the development of low
clouds and fog. Some of the fog could become dense.
Forecast lows range from upper 40s to upper 50s using a blend of
the NBM and its 50th percentile. This is relatively warmer for
the coastal areas due to the abundance of low clouds and fog as
well as light onshore flow.-- End Changed Discussion --
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
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For Thursday, the morning low clouds and fog will get scoured
out with diurnal heating and vertical mixing in the boundary
layer. The fog and low clouds shift south of Long Island and
dissipate, with a mostly sunny day expected.
Winds are pretty light but increase in the afternoon with sea
breeze development.
Used a combination of MAV MOS, MET MOS, NBM and consensus of raw
data for forecast highs Thursday ranging from low 70s across SE
CT and Eastern LI to upper 80s within parts of NE NJ and Lower
Hudson Valley. This combo keeps cooler temperatures along the
coast compared to MOS and NBM.
For Thursday night, similar fog and low cloud development
forecast to redevelop along the coast with slight increase in
dewpoints. Otherwise, mostly clear sky conditions farther north
and west across the interior. Lows forecast from lower 50s to
lower 60s.
Regarding the patchy smoke, HRRR forecasts this to move back
southeast but at gradually lowering concentrations as it gets
more dispersed.-- End Changed Discussion --
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
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Stuck fairly close to the NBM through the long term period. Pretty
much every day has a chance of rain in the forecast.
Ridging aloft from the west begins to breakdown on Friday as a
trough drops south from Canada to New England. 850 mb temps warm
into the 16-18C range with surface temps likely reaching the upper-
80s to lower-90s inland with mid/low-80s for coastal areas. A
backdoor cold front is also expected overnight Friday into Saturday
morning. The prefrontal trough will bring PVA and instability
leading to scattered showers and thunderstorms. SBCAPE values are
1000-1500 J/kg from the GFS, but looking higher on the NAM at 2000-
2800 J/kg. Some of the stronger instability occurs inland where
there is also a chance for some possible small hail give colder air
aloft as seen on model soundings.
After the backdoor front passes overnight, we should maintain north
or easterly flow through the weekend with gusting winds 20-25 kts
and maintain it through Monday. High will be much cooler Saturday
thanks to the front, with highs in eastern areas in the mid-60s with
western areas in the low-70s. The trough building in New England
cuts off at upper-levels and slowly retrogrades south and west over
the weekend. The cyclonic flow from this low could lead to daily
shower chances. The lower heights will prevent us from warming up
much through the weekend.
A coastal low riding up the coast will bring more showers for Monday
and Tuesday, also allowing temperatures back into the mid-70s. FROPA
may occur sometime on Tuesday or Wednesday but models do not have a
consensus on timing with this.-- End Changed Discussion --
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
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High pressure remains in the vicinity of terminals for the TAF
period.
VFR through the evening with haze. Low stratus/fog will then return
after 03Z from east to west, bringing MVFR to IFR or lower
conditions. Highest probability of IFR or lower is for NYC terminals
on east.
S winds become variable this evening around 10kt or less. Winds
remain light and southerly into Thursday morning.
Smoke from Canadian wildfires could limit visibilities to around 5SM
at times into this evening. Thus, slant range visibilities may be
reduced to 4sm or less. This may continue into Thursday mainly for
KSWF given the weak flow aloft.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of onset of MVFR to sub MVFR cigs overnight may be off by an
hour or two. It is also uncertain as to how far west the low stratus
will make it, possibly only impacting KEWR/KTEB for only an hour or
two overnight/early Thursday am.
There remains some uncertainty with how much surface restrictions to
sky/vsby there will be with the haze and smoke through this
afternoon.
OUTLOOK FOR 20Z THURSDAY THROUGH MONDAY...
Thursday: Mainly VFR after earlier low stratus clears.
Friday: Mainly VFR. Low chance of showers/thunderstorms and MVFR,
mainly at night.
Saturday: MVFR possible with a chance of showers throughout the day.
NE-E winds near 10-15kt with gusts near 20-25kt, highest at the
coastal terminals.
Sunday: Becoming VFR.
Monday: VFR to start, then MVFR possible in afternoon showers.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
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With a relatively weak pressure gradient remaining across the
local waters, conditions for winds and seas will remain below
SCA thresholds through Thursday night.
Sub-SCA winds and waves expected Friday. SCA conditions expected on
ocean waters Saturday through Monday with gusts of 25-30 kts, waves
5-7 feet.-- End Changed Discussion --
&&
.HYDROLOGY...
No hydrologic impacts expected through early next week.
&&
.TIDES/COASTAL FLOODING...
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A moderate rip current risk is expected through this afternoon
and Thursday.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JM/BR
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...BR
AVIATION...DR
MARINE...JM/BR
HYDROLOGY...JM/BR
TIDES/COASTAL FLOODING...