000
FXUS61 KOKX 311123
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
723 AM EDT Mon Jul 31 2023
.SYNOPSIS...
A weak cold front will pass through the area tonight. High pressure
then builds in and remains in control through the middle of the
week. The high pressure moves offshore on Thursday. The next frontal
system likely moves across the region on Friday and may may linger
nearby on Saturday. High pressure returns by Sunday.
&&
.NEAR TERM /THROUGH TONIGHT/...
The forecast is mainly on track this morning. Made only minor
adjustments to temperatures and sky to capture the latest obs.
It has been another very cool morning as this dry airmass settles
over the area. Current temperatures are in the mid 50s to low
60s for most, with the usual cool spots in the lower 50s. A
shortwave embedded in the longwave trough over the eastern CONUS
can be seen moving overhead on water vapor satellite imagery.
With a lack of moisture overall, the area will remain dry. Just
some very light returns can be seen currently on radar well
south of us.
Daytime heating today and cyclonic flow aloft will lead to a
scattered to broken cloud deck around 7000 ft. A surface trough
will be lingering over the area today and could be a source of
convergence along with possible sea breeze boundaries. Have kept
a slight chance of showers in the forecast, but have removed
thunder. Forecast soundings show very little, if any, CAPE from -15C
to -25C and do not think anything that gets going will be able
to produce lightning. A midlevel cap was also noted in the forecast
soundings around 700mb through much of the day. However, can
not completely rule out an isolated thunderstorm. Low end slight
chance PoPs start at 18z and go through 03z ending from NW to
SE.
A weak cold front moves through late tonight and the flow becomes
N/NW. Winds may stay up a bit too much tonight, so did not go as low
as Sunday night with the lows.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The upper level trough remains over the area through early Wednesday
before the axis shifts to the east. Shortwave ridging will take
place Wednesday night. At the surface, high pressure builds in,
becoming centered over the area Wednesday afternoon.
Below normal temperatures and humidity continues Tuesday and
Wednesday, with no precipitation. With decent radiational cooling
conditions on Tuesday night, used mostly the MOS guidance to capture
low temperatures. The interior could see lows in the upper 40s.
High pressure shifts offshore Wednesday night and a return flow sets
up, which will slowly start to bring in moisture. Cool lows are
still expected, but not as low as Tuesday night.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
No significant changes to the forecast thinking Thursday into next
weekend.
The upper trough axis will continue sliding offshore on Thursday
allowing the surface high to move east of the area. There is
relatively good agreement that another shortwave will attempt to
amplify the upper trough over the northeast Thursday night into
Friday, sending the next frontal system into the region. The
modeling has started to come into better agreement on the timing and
amplitude of the system, which looks to impact the region on Friday.
There may be some shower development Thursday afternoon and evening
under a weak warm advection regime, mainly NW of the NYC metro. The
frontal system and shortwave then provide more organized forcing for
shower and thunderstorm development with probabilities increasing
into Friday. Have capped PoPs off at high chance (50 percent) as
timing and coverage is still a bit uncertain. We should start to be
able to fine tune the timing of the highest probabilities within the
next few days. Instability and moisture should be on the increase on
Friday, supporting the possibility of thunderstorms, especially in
the afternoon and evening. However, it is much too early to
determine specifics with the mesoscale environment and if there is
any severe potential.
The front and energy from the trough should begin moving east of the
area Friday night into Saturday. Some of the latest deterministic
runs have trended towards a faster solution with the upper trough
axis shifting offshore on Saturday and heights rising aloft. The NBM
has kept a low chance PoP over the area on Saturday and do not see
reason to sway from that due to this being 6 days out. A weak ridge
may then move over the northeast to end next weekend leading to
drier and warmer conditions.
Temperatures this period are close to the NBM which yields highs
slightly below normal both Thursday and Friday. Humidity levels will
be on the increase into Friday with dew points likely returning into
the middle and upper 60s, possibly near 70 in some spots. Highs on
Saturday are currently a few degrees warmer than then end of the
week, but could trend a bit higher if the front does progress
faster. Temperatures look to be a bit above normal by the end of
next weekend with the aforementioned ridging.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
VFR. A weak cold front moves across the terminals tonight with high
pressure otherwise in control through the TAF period.
Light NW-NNW flow early this morning increases to around 10 kt
by afternoon. The wind direction may back towards the W in the
afternoon. Late afternoon sea breezes are still expected for
KJFK and KISP. For KBDR and KGON, sea breezes are a bit less
and there is chance winds stay W or WNW through the day.
An isolated shower is possible late this afternoon and evening, but
not enough coverage to include in the TAF.
Winds shift back to the NW tonight and fall under 10 kt, then
become N to NNE into Tuesday morning.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of sea breeze at KJFK could be off by 1-3 hours. Sea breeze
should remain SE of KLGA, but low chance it briefly reaches the
terminal by early evening.
Occasional gusts 15-18 kt possible at KEWR this afternoon.
OUTLOOK FOR 12Z TUESDAY THROUGH FRIDAY...
Tuesday through Wednesday night: VFR.
Thursday: Mainly VFR. Chance of showers, mainly NW of the NYC metro
in the afternoon and evening.
Friday: Chance of showers and thunderstorms with MVFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
A Marine Weather Statement continues for Long Island Sound. The
US Coast Guard still indicates a large debris field caused by
recent flooding across New England.
Sub-SCA conditions are expected through Thursday night with a
fairly weak pressure gradient in place. Southwest winds will
increase this afternoon/evening ahead of a cold front, but gusts
are expected to only be up to 20 kt.
A S flow then increases on Friday ahead of the next cold front,
which could bring winds near 25 kt on the ocean waters. Winds
should weaken Friday night with seas subsiding below 5 ft by
Saturday.
&&
.HYDROLOGY...
There are no hydrologic concerns through the weekend.
&&
.TIDES/COASTAL FLOODING...
There is a moderate risk of rip currents today and a low risk
on Tuesday.
Astronomical tides continues to increase early this week with a full
moon on Tuesday, August 1st. About a quarter to three quarters of a
foot of surge is needed to reach minor benchmarks for the most
vulnerable locations along the south shore back bays and Western
Sound along Southern Fairfield for this evenings high tide. Have
issued a coastal flood statement for these locations. Additional
minor flooding is possible with Tuesday and Wednesday evenings and
Statements and/or Advisories may be needed.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...DS/JT
NEAR TERM...JT
SHORT TERM...JT
LONG TERM...DS
AVIATION...DS
MARINE...DS/JT
HYDROLOGY...DS/JT
TIDES/COASTAL FLOODING...