discussion on 2023-06-28

000
FXUS61 KOKX 282348
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
748 PM EDT Wed Jun 28 2023

.SYNOPSIS...
A cold front slowly pushes through tonight, followed by weak high
pressure building across Thursday and Thursday night. The high
then builds offshore for the end of the week. A frontal system
approaches for the weekend, and stalls near the area into the
beginning of next week.

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
-- Changed Discussion --A cold front will slowly push through tonight from west to
east. Lingering shower and t-storm activity should continue to
wane throughout the evening with loss of daytime heating. At the
same time the mid and upper level height fields will begin to
gradually rise as the trough begins to deamplify. Skies should
partially clear tonight as drier air begins to gradually bleed
in from the west. The winds are expect to remain fairly light
and be more out of the NW. The main question tonight deals with
how much smoke and lower air quality with respect to particulate
matter can start to push in from the west. The models have not
been handling this very well with poor initiations with the
various model runs. Have accounted for a slight reduction in
visibility in the grids for western portion of the CWA, and took
more of the experimental RRFS and Canadian RAQDPS approach with
the near sfc smoke forecast in comparison to the operational
HRRR.

Lows tonight will remain near seasonable levels as temps eventually
level off primarily in the 60s, with middle and upper 60s across the
NYC and NE NJ metro areas.-- End Changed Discussion --

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
-- Changed Discussion --Model guidance continues to show slow height rises and continued
deamplification of the mid and upper level trough that has been in
place. A weak high gradually works in throughout the day from the
west. BUFKIT soundings indicate enough of a cap above 5 kft to
likely preclude any convective development and no trigger to lift
air above this CAP in any meaningful way. The limit to convection
should be some moderately building cu along sea breeze boundaries
towards late morning and early afternoon as the synoptic flow will
remain rather weak. Thus, sea breezes form and push inland during
the afternoon. With partly to mostly sunny skies look for
temperatures to reach seasonable levels, with mainly lower and
middle 80s.

For Thursday night with weak high pressure overhead look for partly
cloud to mostly clear skies with dry conditions. The winds will be
light to calm with seasonable temperatures once again. Lows should
range from lower 60s across much of the interior, and middle and
upper 60s closer to the coast and across the metro areas.

With respect to air quality and any potential near surface smoke, as
mentioned in the previous section have stuck close to RRFS and
Canadian RAQDPS guidance. This translates to visibilities down to
around 5-6SM farther west, with little noticeable or discernible
reduction in visibility farther east.-- End Changed Discussion --

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
The models were in fairly good agreement in the extended, so the NBM
was followed.

On Fri, high pres builds offshore with return flow setting up.
Likely an enhanced sea breeze on the south coast by the end of the
day. Dry in the mid lvls, and with the next significant wave still
progged to be over wrn PA, a dry day has been fcst.

Flow aloft becomes generally wly Fri ngt into at least Mon. Remnant
convectively induced waves will provide periodic triggers and
therefore chances for shwrs and tstms thru the period. In addition,
a frontal boundary may stall invof the area Sun and Mon. This would
serve as an additional focus for shwrs and tstms, and allow for some
stronger storms as well. Placement of the front is currently
progged to set up just north of the area thru the period, keeping
the cwa in the warm sector, and areas closest to the boundary in a
region of better shear. Still too far out to have high confidence
however.

Upr low currently over the wrn conus may impact the region for the
4th. Low confidence wrt timing this far out, but the ECMWF is faster
than the GFS, getting the remnant upr feature here by the end of
Mon. The GFS timing is for Tue however.

Some diurnal convection possible behind the feature on Wed with
relatively lower heights and July sun.

The NBM was used for temps thru the period. If the front remains
north of the area for the beginning of the week, some of the usually
hotter areas could end up around 90 for highs by Mon and Tue.

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --A cold front will move across this evening, and continue to pass
to the east as high pressure sets up to the west.

Mainly VFR, with some lingering showers near KJFK/KISP/KGON
early as well as S-SW flow less than 10 kt. Otherwise, expect
post-frontal NW flow, with BKN VFR cigs scattering out after
midnight. Coastal sea breezes should start up by late AM or
midday at KBDR/KGON, but should take a couple hours later than
usual at KISP/KJFK/KLGA, direction more SW than S to start.

Some haze likely from the NYC metros north/west during much of
the daytime hours.

...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

No unscheduled AMD expected.

OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY...

Thursday night and Friday: VFR.

Friday night: Chance of showers/MVFR cond, with possibly a tstm
at KSWF.

Saturday and Sunday: Showers likely and chance of tstms, mainly
each afternoon/evening. MVFR expected, IFR possible with this
activity.

Monday: MVFR possible. Chance of mainly afternoon/evening
showers and thunderstorms.

Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --

.MARINE...
Ocean seas are expected to gradually lower from west to east tonight
with small craft conditions coming to an end by midnight for the
western most ocean waters, and the early morning further east.
Weak high pressure will provide a light to non- existent pressure
gradient leading to a light wind regime into Thursday. Seas will
subside closer to 4 ft on average through Thursday night. Winds
and seas are generally expected to remain blw sca lvls Fri- Mon.
There will be chances for tstms by Sun and Mon, which could
result in locally hazardous conditions.

.HYDROLOGY...
Drier air gradually works in tonight into Thursday. This should
bring the localized heavy rain threat to an end for late this
week. At this time no widespread hydrologic impacts are expected
Fri- Tue.

.TIDES/COASTAL FLOODING...
-- Changed Discussion --With a southerly flow continuing and building seas, the rip current
risk today is high. The risk lowers to moderate on Thursday and
Friday.-- End Changed Discussion --

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --CT...None.
NY...Air Quality Alert until midnight EDT Thursday night for
NYZ067>075-078>081-176>179.
High Rip Current Risk until 9 PM EDT this evening for NYZ075-
080-081-178-179.
NJ...Air Quality Alert from midnight tonight to midnight EDT
Thursday night for NJZ002-004-006-103>108.
MARINE...Small Craft Advisory until 6 AM EDT Thursday for ANZ350-353.
Small Craft Advisory until midnight EDT tonight for ANZ355.-- End Changed Discussion --