128
FXUS61 KOKX 130750
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
350 AM EDT Tue Aug 13 2024
.SYNOPSIS...
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A series of weak surface troughs will move across the area
through Thursday. Weak high pressure will otherwise remain in
control through the end of the week. A weak frontal system
will slowly approach from the west from Friday night into
Monday.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH TONIGHT/...
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Upper trough that moved through Monday evening will continue
pushing off the New England coast today. Broader troughing will
remain aloft over the northeast with high pressure continuing to
nose in from the west. There are no organized shortwaves or
areas of forcing compared to Monday, so the forecast remains
dry. Forecast soundings indicate fairly deep mixing up to 4-6
kft. There is a thin layer of moisture at the top of the mixed
layer which should yield scattered clouds in the afternoon.
There is also some very shallow instability. CAMs are simulating
some light returns in the simulated reflectivity fields.
However, this may be more of a signal of the cloud field rather
than actual showers. Do not think there will be measurable
precip given the shallow moisture, subsidence, and dry subcloud
layer. However, a sprinkle cannot be ruled out. Otherwise, highs
will once again be a few degrees below normal in the upper 70s
and lower 80s.
Tonight will feature mostly clear skies with seasonably cool
temperatures in the upper 50s inland and lower to middle 60s
elsewhere.
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
The broad upper trough will remain anchored over the region, but
there will likely be some retrogression of an upper low within
the trough Wednesday into Wednesday night. The models are
indicating the upper low will move from near the Maritimes
southwest towards Maine. The sensible weather over the Tri-State
should not change much, but there will likely more organized
shortwave energy rotating around the upper low, which may aid in
the development of a few showers for inland areas of the Lower
Hudson Valley and Connecticut Wednesday afternoon. Instability
still looks weak/shallow and have left mention of thunder out
of the forecast for now. Temperatures will moderate compared to
recent days with highs in the low to middle 80s across the
region, slightly above normal for this time of year.
Another round of shortwave energy aloft dives southward around
the upper low, which only slowly shifts east, late Thursday
into Thursday night. High pressure will remain just to the west
with the likelihood of a weak surface trough over the area on
Thursday afternoon/evening. Forcing and instability look to
maximize across eastern CT Thursday afternoon and evening,
supporting a bit higher probabilities (chance) for showers and
thunderstorms. Otherwise, isolated convection is possible
westward into the Lower Hudson Valley. Have left PoPs below 15
percent towards the coast and NYC for now as sea breezes may
stabilize the low levels to prevent convection from making it
that far south. Highs look seasonably warm in the lower to
middle 80s.-- End Changed Discussion --
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
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Wx on Friday should be dry as shortwave ridging aloft slides
across. Then chances for showers/tstms increase going into the
weekend and early next week as a longer wave upper trough and
associated sfc frontal system approach. Its forward motion will
be slowed down by downstream ridging and also the passage of
Ernesto to the east on Sunday.
The frontal system may start to make some forward progress on
Monday, but still have chance PoP in the forecast as additional
shortwave energy drops into the longwave trough and keeps it
anchored in place to the west.
Temps on Fri and Mon should be slightly above normal, with near
normal temps this weekend.-- End Changed Discussion --
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
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A surface trough will linger over the area today. There could
be some BKN mid level clouds at times this afternoon, with
flight cat remaining VFR.
NW winds at most of the NYC metro terminals were still either side
of 10 kt as of 07Z-08Z, and these winds will probably last until 11Z-
12Z when winds just off the deck diminish. Otherwise, NW flow less
than 10 kt may veer more northerly for a time this morning, then
once again become NW closer to 10 kt this afternoon, with some gusts
possible at the NYC metros especially KEWR.
A SW flow should develop later than usual at KJFK/KISP/KGON due
to presence of the trough and a sea breeze attempting to develop.
There is the slight chance it could also develop at KBDR late in the
afternoon, and push northward to KLGA this evening.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Low confidence on sea breeze timing at KJFK this afternoon. A
light SE-S sea breeze may make it to KLGA this evening.
OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...
Late tonight through Friday: VFR.
Saturday: Chance of showers with MVFR cond possible.
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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High pressure provides a weak pressure gradient and a light wind
regime overall through Thursday night. Seas will also remain well
below SCA levels.
The combination of an approaching frontal system Fri night into the
weekend along with building long period swells from Ernesto will
allow for ocean seas to build rapidly to SCA levels, going from 2 ft
late Fri afternoon to 5-6 ft by daybreak Sat, with some sets as high
as 7 ft Sat afternoon.-- End Changed Discussion --
&&
.HYDROLOGY...
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There are no hydrologic concerns through the end of the week.
It is too early to know what, if any, impacts may arise from an
approaching frontal system this weekend.-- End Changed Discussion --
&&
.TIDES/COASTAL FLOODING...
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There is a low rip current risk through Wednesday.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...BG/DS
NEAR TERM...DS
SHORT TERM...DS
LONG TERM...BG
AVIATION...BG
MARINE...BG/DS
HYDROLOGY...BG/DS
TIDES/COASTAL FLOODING...