000
FXUS61 KOKX 071423
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1023 AM EDT Wed Jun 7 2023
.SYNOPSIS...
Low pressure will weaken over the Canadian Maritimes weakens
today as it drifts back to the west along the New England coast
into Thursday. A surface trough dropping south on the backside
of the low will pass through the forecast area later this
afternoon into this evening. A series of troughs will then move
across the area Thursday into Friday. Weak high pressure builds
in Friday night into Saturday and moves offshore Saturday night
into Sunday. A frontal system impacts the area Monday and
Tuesday.
&&
.NEAR TERM /THROUGH TONIGHT/...
Forecast remains on track this morning. Main concern will again
be with smoke/haze from wildfires across eastern Canada. We are
still seeing hazy skies this morning. The expectation is the low
level smoke will increase in concentration heading into the
afternoon as another significant push comes down from the north
and west. The latest RAP/HRRR continue to indicate this
occurring, which will likely yield low visibilities, poor air
quality and the smell of smoke. This higher amount of low level
smoke likely persists into the early evenings hours. Portions of
southeast CT may see slightly better conditions this evening as
the low pressure over northern New England tries to push the
smoke further south.
A cutoff upper low over the Canadian Maritimes will gradually
weaken over the next couple of days while working west across
northern New England. A surface trough rotating southward on
the backside of the low will move across the area late this
afternoon into early this evening. CAMs continue to show any
showers with the trough to be across southeast CT and eastern
LI. Otherwise, looking for a mainly dry day with mostly sunny
skies to start, but filling in with some clouds due to steep
mid level lapse rates and deep cyclonic flow. Any shower
activity ends early this evening.
NW winds will back around to a more westerly direction this
afternoon with possible seabreeze development along the south
shore of LI. Light northerly winds follow behind the trough
tonight.
It will be another seasonably warm day with highs mainly in the
70s, but possibly as high as 80 across metro NJ. Lows tonight
will range from the upper 40s inland, to the upper 50s across
the NYC metro. This is slightly below normal with some cooler
air wrapping around behind the low and into the areas.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
The upper low becomes nearly stationary across northern New
England during this time in what remains a highly amplified and
blocked flow across North America. The upper trough axis rotates
southeast and across the area on Friday. This will result in
increasing chances of showers each afternoon, especially Friday
afternoon with the upper trough axis overhead. Airmass is fairly
stable but there could be isolated thunderstorms Friday. Rainfall
amounts during this time look to be light with less than a
quarter inch forecast.
Clouds will also become more prevalent with the placement of the
upper flow and moisture being wrapped around the large upper
vortex. This will result in a gradual cool down into Friday.
Highs on Friday will struggle to get much higher than the upper
60s to around 70. Leaned toward the cooler MOS guidance versus
the NBM.
Hires guidance also pointing to smoke concerns lingering into
Thursday, but confidence is not high.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Upper closed low pressure remains over Northeast Friday
night and weakens into a trough, while the surface low dissipates
into Saturday. The longwave trough remains across eastern Canada and
another shortwave will move into the Great Lakes region Sunday,
developing into another closed low that induces a surface low late
Sunday night into Monday morning over the central Great Lakes
region. The attendant warm and cold fronts will slowly
approach the area through Monday night and then move
through Tuesday. The now stacked low will remain over the
Great Lakes region Monday through Monday night, then head
northeast and pass well north and west of the forecast area into
Wednesday.
Generally unsettled weather will impact the area
through much of the long term with a chance of showers, and
thunderstorms Friday night into Saturday. Saturday night into Sunday
look to be dry with weak high pressure over the area. The surface
low and cold front impacts the area later Monday into Tuesday with
chances for showers and thunderstorms once again, mainly during the
afternoon and evening hours.
Temperatures will be below seasonal levels Friday, and
return to more seasonal levels Saturday into the beginning of next
week.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
Any VFR conditions for eastern terminals will drop to MVFR this
morning as thicker areas of smoke move into the area. Thicker
smoke is expected to move into the entire area through 18Z. This
will further reduce visibilities, likely into the IFR category
with visibilities below 3 miles. However, there is a good deal
of uncertainty and the forecast may be off by +/- a few hours.
NW winds increase this morning to 10-15 kt. A shift to the W is
expected in the afternoon at speeds of 10 to 15 kt. Gusts up to
20 to 25 kt are possible but uncertain. Coastal terminals like
KJFK, KISP, KBDR and KGON shift to the W to SW late in the day.
However, there is more uncertainty with this wind shift due to
sea breeze at KJFK and KBDR.
There is a slight chance for showers this afternoon and evening,
but mainly affecting KGON. Brief MVFR conditions are possible
with these showers, outside of those caused by smoke.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
The afternoon haze potential forecast is RED, which implies
slant range visibility less than 4SM outside of cloud.
Visibilities will continue to lower through 18Z today. Visibilities
could be reduced to as low as 2 SM at times in smoke with
amendments possible. The smoke could limit slant range
visibilities to less than 4 SM as well.
OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
Thursday through Friday: Mainly VFR. Chance of afternoon and
early evening showers both days. HZ may reduce visibilities to
MVFR Thursday morning.
Saturday: Mainly VFR. Chance of MVFR conditions late in shra or
tsra, mainly for northern terminals.
Sunday: Mainly VFR. Chance of MVFR conditions towards evening and at
night in shra.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Winds and seas likely remain below SCA levels through the
upcoming weekend with a relatively weak pressure gradient in
place. Low pressure moves away from the waters Friday night
into Saturday as weak high pressure builds in for Saturday and
then east on Sunday.
&&
.HYDROLOGY...
No hydrologic impacts expected through the beginning of next week.
&&
.TIDES/COASTAL FLOODING...
Water levels continue to gradually fall in conjunction with
astronomical tides. In addition, an easterly swell from low
pressure over the Canadian Maritimes will subside. That being
the case, it`s still possible for the high tide cycles the next
few nights to get close to minor coastal flood benchmarks
across the south shore back bays of Nassau. A statement is
possible, but confidence is not high enough at this time to
issue.
There is a low risk for the development of rip currents at the
ocean beaches today and Thursday due to a diminishing swell and
weak winds.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JP/DW
NEAR TERM...DS/DW
SHORT TERM...DW
LONG TERM...JP
AVIATION...JP/MW
MARINE...JP/DW
HYDROLOGY...JP/DW
TIDES/COASTAL FLOODING...