000
FXUS61 KOKX 272011
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
411 PM EDT Tue Jun 27 2023

.SYNOPSIS...
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A slow moving frontal system will impact the area through
Wednesday. High pressure will briefly build in on Thursday, and
move east on Friday. An upper level disturbance will approach
late Friday, then a slow moving warm front will approach this
weekend. A weak cold front will pass east on Monday.
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&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
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Instability will continue to increase thru the end of the day
with little to no CIN. The NAM has underestimated SBCAPE to the
per LAPS, with some swrn portions of the cwa over 1000 J/kg as
of 18z. Isold-sct development is expected thru 00Z. Favored
areas remain west of the Hudson, particularly NJ zones with
tstms already showing up over PA. Bulk shear is fairly weak, so
multicellular should be the main mode for tstms. Main threat
today would be damaging winds.

Storm motion is progged to be only around 5 kt thru this eve,
so there will be an isold flood threat in any heavier activity.
The HWO has been updated to account for this.

As the strongest mid and upr lvl winds depart early this eve,
activity expected to be mainly tied to the approach of the mid
lvl trof axis, which was over wrn PA this aftn, as well as any
convective outflows and boundaries around the cwa. Have keep
pops in the sct category for the overnight period due to the
lack of any jet forcing.

Some patchy fog will be possible late tngt into Wed mrng with
light flow and residual moisture in place.

Temps close to the NBM tngt.
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&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
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The upr trof and associated frontal boundary slowly works across
the area thru the period. Llvl sly flow continues thru the day
on Wed, so additional shwrs and tstms are expected to develop.
Best focus across the interior into CT attm just ahead of the
sfc front and with the best instability. The front works across
the area overnight, resulting in decreasing pcpn chances by Thu
mrng.

Temps close to the NBM thru the period.
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&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...

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As an upper trough exits, sfc high pressure should build in for
Thu and remain into at least part of Friday, with temps a few
degrees above normal. Cano`t rule out an isolated afternoon
shower or tstm across S CT and the lower Hudson Valley as a weak
thermal trough and and passing mid level shortwave impulse
combine to provide some modest lift.

A weakening shortwave trough aloft may help spark a few
showers/tstms from late day Fri into Fri night, then an
unsettled weekend appears to be shaping up as a sfc warm front
approaches from the SW and as quasi-zonal flow aloft between an
upper high over the TN Valley and deep South and an upper low
over Ontario brings a series of mid level impulses across to
help spark multiple rounds of showers/tstms. Timing of the last
of these is in question, and forecast still carries chance of
diurnal tstms into Mon/Tue for areas NW of NYC.

Temps this weekend will be a few degrees below normal due to
expected cloud cover and precip. Warmer cond expected for
Mon/Tue, and with increased humidity heat index values could
surpass 90 both days in the urban corridor of NE NJ.
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&&

.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
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A slow moving frontal system lingers nearby with weak low
pressure developing late tonight into Wednesday.

Prevailing VFR until a line of showers and thunderstorms approaches
towards 22Z-24Z for city and western most terminals. Thus
expecting the remainder of this afternoon to be dry. Have
TEMPO groups of tsra in TAF`s approaching 00Z for the city
terminals and points west. Questions remain as to exactly how
far east any showers and storms can get this evening as
thunderstorm survival is less likely further east.

S to SSE winds increasing to 10-15 kt this afternoon,
diminishing tonight outside of any thunderstorms. The winds go
light and variable late tonight at most terminals. The winds
then have a more westerly component to them towards daybreak and
increase some out of the SW Wed morning.

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

High uncertainty as to how far east any thunderstorms can get
this evening. Have maintained TEMPO for TSRA, with AMD remaining
a good possibility for timing, and possibly occurrence for
KJFK and KLGA.

OUTLOOK FOR 18Z WEDNESDAY THROUGH SATURDAY...

Wednesday afternoon: Mostly VFR, with TSTMs and brief MVFR possible
until evening in any storms.

Thursday: Mainly VFR. CHC of shra/TSTM/MVFR in the afternoon, mainly
north of the city.

Friday through Saturday: Chance of showers and thunderstorms.
Mainly VFR Friday with a chance of MVFR. MVFR to IFR Saturday.

Sunday: MVFR possible in showers and thunderstorms.

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

.MARINE...
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The SCA on the ocean has been extended thru Wed night. The advy
is mainly for seas. On the protected waters, winds and waves,
outside of tstms, are expected to remain blw sca lvls thru the
period.

Mainly quiet for the long term, with winds and seas remaining
below SCA criteria.
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&&

.HYDROLOGY...
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A localized risk of flash flooding continues into this eve,
especially across NE NJ and the lower Hudson Valley where ffg
is lowest. Any significant tstms however will be capable of
producing localized flooding in urban and poor drainage areas.

Hydrologic impacts are also possible on Wednesday and again this
weekend.
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&&

.TIDES/COASTAL FLOODING...
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The rip current risk is high today and Wednesday due to stronger
S flow and higher seas.
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&&

.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...None.
NY...High Rip Current Risk until 9 PM EDT this evening for NYZ075-
     080-081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EDT Thursday for ANZ350-353-
     355.
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&&

$$
SYNOPSIS...JMC/BG
NEAR TERM...JMC
SHORT TERM...JMC
LONG TERM...BG
AVIATION...JE
MARINE...JMC/BG
HYDROLOGY...JMC/BG
TIDES/COASTAL FLOODING...