000
FXUS61 KOKX 061950
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
350 PM EDT Wed Sep 6 2023
.SYNOPSIS...
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High begins to weaken on Thursday. A slow moving frontal system will
impact the area Thursday night through the weekend. The
associated cold front passes through late Sunday night into
Monday. A second frontal system will follow on its heels
Tuesday.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH TONIGHT/...
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An upper level ridge will remain over the area tonight. Tonight will
remain mostly clear, warm, and muggy. Overnight lows for much of the
CWA will drop into the 70s. Record maximum lows are also possible
for some climate sites tonight.-- End Changed Discussion --
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
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The upper level ridge starts to weaken and slide east Thursday.
Despite this, the hot and humid conditions will remain in place
Thursday afternoon. Heat advisories remain in effect for NYC,
western Long Island, the Lower Hudson Valley and portions of NE NJ
and Connecticut.
Record high temperatures are possible on once again for some climate
sites. Also, the warm conditions continue overnight so record
maximum lows will once again be possible Thursday night. You can
reference the climate section of this AFD for a listing of prior
records.
Isolated showers and/or thunderstorms are possible for western
interior portions of our area Thursday night from a weak frontal
system that could impact us into the weekend. This is also where
SPC has highlighted a slight risk for severe thunderstorms.
This is primarily for an increased risk in isolated severe wind
associated with some of the thunderstorms.-- End Changed Discussion --
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
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The Tri-State will lie between Western Atlantic ridging and a
broad/disjointed upper level trough from the Ohio Valley down to the
southeast Friday through the weekend. There will likely be multiple
pieces of energy that get moved from south to north between the
ridge and trough. The flow between the two systems will also allow a
deep-layered southerly flow to advect subtropical moisture
northward.
The modeling has continued to trend towards the ridge retrograding a
bit on Friday which will ultimately confine convective chances to
the western half of the area (along Hudson River corridor on west)
in the afternoon and evening. There has been some consistency with
the last few model cycles with some shortwave energy lifting across
the Lower Hudson Valley. A frontal system will also lie just to our
west. Think greater coverage of convection ends up west of the area
with the frontal system as the focus, but some scattered activity
should occur west of the Hudson River corridor. The Storm Prediction
Center currently has the western half of the area in a Marginal Risk
for severe thunderstorms.
The front does not move much on Saturday and upper level pattern is
very similar to Friday. There may be a bit more organized shortwave
energy lifting towards the area from the south in the afternoon and
evening. The ridge may start to slowly push east Sunday allowing a
bit more height falls and a nudge eastward with the frontal system.
This should raise probabilities of precip further east in the
afternoon and evening.
Friday into the weekend will not be a washout and it will not be
raining the whole period. The timing of any individual piece of
energy and associated lift is uncertain, but have gone with the more
usual diurnal timing for higher probabilities. Portions of Long
Island and southern Connecticut may not see any convection until
late Sunday given the proximity of the ridging.
Localized heavy rainfall is possible in any of the
shower/thunderstorm activity with any flash flood potential
remaining localized. Average rainfall around a quarter of an inch or
forecast Friday through Saturday in the NYC metro, but are closer to
an inch into the interior of the Lower Hudson Valley. With
additional convection on Sunday, these amounts could ultimately end
up higher when totaling the several days of potential rainfall.
The upper trough flattens further as it begins to move across the
northeast on Monday. The cold front may be stalled over the area or
begin to wash out or wash out. There is still a chance of a few
showers on Monday. Model consensus has trended towards a more humid
air mass lingering on Monday as well since the front may take much
of the day to pass east. A slight air mass change should occur early
next week, but there is a second frontal system on its heels with an
amplifying upper trough digging south and east across the Great
Lakes. Chances for convection will be on the increase ahead of this
system Tuesday and Wednesday.
Friday will be the warmest day of the period with highs in the
middle and upper 80s. Some spots in NE NJ could touch 90 degrees.
Heat indices should largely remain in the lower 90s and do not
anticipate an extension of the Heat Advisory into Friday at this
time. Highs on Saturday look to be in the lower to middle 80s and
then highs look to be closer to normal in the upper 70s to around 80
Sunday into early next week.-- End Changed Discussion --
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
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High pressure remains offshore with a weakening trough across
the local region going into this evening.
VFR conditions are expected to continue for most terminals
through the TAF period. Some patchy light fog reducing
visibilities to MVFR is forecast for KSWF and KGON late tonight
into early Thursday morning.
Winds will be near or less than 10 kts during the TAF period. The
wind direction will be more variable, and will be more dependent on
the trough and sea breezes. Tonight into Thursday morning, wind
speeds will be near 5 kts or less with variable direction with more
of a south wind near 5 to 10 kts Thursday afternoon.
Specifically into start of this evening, sea breezes are expected
for CT terminals and for KJFK. Beyond those terminals, sea breeze
timing for KLGA and KISP is more uncertain. The transition will be N
flow to more S flow for both terminals by early this evening. The other
terminals will remain more W to NW wind direction.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of sea breeze for early evening for KLGA could be 1-2 hours
off from TAF.
Low chance of a sea breeze late this afternoon into early this
evening for KEWR and KTEB.
OUTLOOK FOR 18Z THURSDAY THROUGH SUNDAY...
Thursday: Mainly VFR. S/SW winds. Chance of showers and
thunderstorms to the north and west of NYC terminals afternoon
into evening. A slight chance of showers and thunderstorms
for NYC terminals, KHPN and KBDR late afternoon into evening.
Friday through Saturday: MVFR possible at times in rounds of
showers and thunderstorms, mainly afternoon through evening.
Potential for nocturnal coastal stratus will increase through this
period as well. Showers likely Saturday afternoon into Saturday
evening near and northwest of NYC terminals.
Sunday through Monday: MVFR possible at times. Possible late
night into early morning coastal stratus. Chance of showers,
slight chance of thunderstorms. Showers likely for most
terminals Sunday afternoon into early Sunday evening.
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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Sub-SCA conditions are expected through Thursday.
Winds and seas are expected to remain below SCA levels Friday
through early next week with a weak pressure gradient.-- End Changed Discussion --
&&
.HYDROLOGY...
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Locally heavy rain is possible with isolated thunderstorms for
western interior locations Thursday night.
Locally heavy rainfall is possible Friday into the weekend. The
greatest coverage looks to lie along and west of the Hudson River
corridor Friday into Saturday, with chances areawide on Sunday.
There is still uncertainty with the timing and extent of individual
rounds of showers/storms. Localized flash flooding is possible in
any heavier activity that develops.-- End Changed Discussion --
&&
.TIDES/COASTAL FLOODING...
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A moderate risk of rip currents exists on Thursday with lingering
ESE swells and a stronger S flow developing in the afternoon. The
strong south flow continues on Friday which likely builds seas to 3
ft. Swells may still linger so have gone with a moderate risk of rip
currents on Friday.-- End Changed Discussion --
&&
.CLIMATE...
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Some daily record highs and lows could be tied or broken over the
next couple of days. The records for these dates are below.
Daily Record High Temperatures...
Sep 7
Central Park..101(1881)
LaGuardia.....90 (2015)
JFK...........93 (1983)
Islip.........92 (1998)
Newark........95 (2015)
Bridgeport....91 (1983)
Daily Record High Minimum Temperatures...
Sep 7 Sep 8
Central Park..79 (1881)..76(2015)
LaGuardia.....74 (2012)..76(2015)
JFK...........76 (1985)..73(1983)
Islip.........74 (2012)..76(2015)
Newark........74 (1999)..73(1999)
Bridgeport....72 (2016)..74(2015)-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Heat Advisory until 8 PM EDT Thursday for CTZ005>009.
Heat Advisory until 8 PM EDT this evening for CTZ010>012.
NY...Heat Advisory until 8 PM EDT Thursday for NYZ067>075-176-178.
Heat Advisory until 8 PM EDT this evening for NYZ078-080-177-
179.
NJ...Heat Advisory until 8 PM EDT Thursday for NJZ004-006-103>108.
MARINE...None.
&&
$$
SYNOPSIS...BR
NEAR TERM...BR
SHORT TERM...BR
LONG TERM...DS
AVIATION...JM
MARINE...BR/DS
HYDROLOGY...BR/DS
TIDES/COASTAL FLOODING...DS
CLIMATE...