718
FXUS61 KOKX 290158
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
958 PM EDT Wed Aug 28 2024
.SYNOPSIS...
A cold front sags south of the area tonight. High pressure gradually
builds from the north and northeast through Friday. A frontal system
will affect the area this weekend. Canadian high pressure builds in
thereafter and will remain in control through at least the middle of
next week.
&&
.NEAR TERM /THROUGH THURSDAY/...
-- Changed Discussion --
A couple of showers, and possibly an isolated thunderstorm have
developed across eastern Long Island Sound and the eastern Long
Island bays at 0130Z. The other area of showers and
thunderstorms was moving south of western Long Island into the
adjacent marine waters. HRRR shows all the convection quickly
weakening in by 04Z.
The change in air mass appears to be a little more delayed
compared to previous NWP cycles. Now the drier air takes a few
hours longer to drain into the region. Dew point readings drop
gradually through the 60s. The more noticeable drop in humidity
and improved comfortability takes place into Thursday morning.
Clouds will linger behind the cold front, and thus temperatures
remain a bit more elevated despite a northerly flow. Slight
chance PoPs were kept for SW sections into the pre-dawn hours.
Low temperatures will be in the 60s region wide.
With the southern edge of high pressure attempting to nose in from
the north conditions should remain primarily dry on Thursday. Some
shower and convective activity takes place off to the west later in
the day over Central PA, and could get into Eastern PA late. Have
maintained slight chance PoPs for later in the day for the western
half of the area with 15 to 20 percent PoPs. Otherwise expect
variably cloudy to mostly cloudy skies and much more comfortable
conditions with temperatures likely getting to about 5 degrees below
average for the day Thursday. Daytime highs will be in the middle
70s for the most part due to more cloud cover and a prevailing
easterly flow.-- End Changed Discussion --
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/...
The forecast gets a little more complicated for Thursday night. The
evening should remain dry for the most part, with perhaps a few
showers getting into the western half of the region. Convective
chances will be limited with the boundary layer quite stable with an
onshore flow. An elevated warm front looks to slowly get slightly
further east through late Thursday night. Have slight chance to
minimal PoPs further east, with chance PoPs further west. Some
elevated convection cannot be completely ruled out for the western
periphery of the CWA later Thursday night into Friday morning, but
appears unlikely. An onshore flow will be locked in out of the east.
Temperatures will be a touch cooler with upper 50s to middle 60s
across the area.
High pressure builds along the New England coast and into the Gulf
of Maine on Friday. This should hold off precip throughout the day,
with more clouds further south and west, with less in cloud cover to
the northeast in closer proximity to the high. Skies will likely
average out partly cloudy for the most part with temperatures
running a few degrees below normal with the onshore flow
continuing.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
The long term period starts off dry Friday night with shortwave
ridging aloft and also a surface ridge lingering over the area from
offshore high pressure. Off to our west, a cold front approaches the
area. By late Saturday morning the surface ridge will weaken and as
the flow becomes southerly a plume of moisture will spread over the
area. Some showers are possible with this warm front in the morning
hours, but the bulk of any showers/thunderstorms will likely move
through Saturday evening/Saturday night ahead and along the actual
cold front. The latest GFS run shows pwats around 2 inches right
ahead of the cold front, which could allow for some heavy downpours,
but at this time the system looks progressive enough for hydro
impacts to be minimal. Also, the late timing of the front is
favorable for our area, with the loss of daytime heating leading to
lower instability.
A secondary push of cold air is expected later on Sunday, but the
airmass will likely be too dry for any showers/thunderstorms.
Canadian high pressure then builds in, bringing a dry and cool
airmass to the region. Dewpoints look to drop to the mid and upper
40s Monday night and then could stay around there through at least
mid week. Highs will be around 10 degrees below normal for early
September on Tuesday and Wednesday.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
A cold front continues to move slowly southward through the
terminals and will be south of Long Island 02Z to 03Z. High
pressure then builds in from eastern Canada through Thursday.
VFR. Area of showers and isolated thunderstorms was moving
through the NYC metro terminals at 0145Z and will be quickly
weakening as the area moves into the waters south of Long
Island. Forecast is on track and convection should be south and
east of the terminals by 03Z.
Southwest to west winds ahead of the front switch to the NNW to
NE with the passage of the front, and as the high builds
farther to the south and east. Winds then become easterly around
10 kt Thursday morning.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Showers and isolated thunderstorms will be south of the
terminals by 03Z, and weaken.
OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY...
Thursday night: VFR. A slight chance of showers western
terminals.
Friday: VFR. A slight chance of showers.
Saturday: VFR, a chance of showers, possibly thunderstorms with MVFR
or lower. Showers and thunderstorms likely at night with MVFR or
lower.
Sunday: Mainly VFR. Chance of a shower/thunderstorm,
mainly in the afternoon and evening.
Monday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Sub small craft conditions are expected to prevail tonight through
Friday. A period of marginal small craft gusts and potentially seas
is anticipated for the central and eastern ocean from the early
morning through the early evening on Thursday. But by and large seas
are not expected to remain above 4 ft.
Winds and waves will generally remain below Small Craft Advisory
criteria this weekend into early next week. There is a chance that
gusts may occasionally reach 25 knots ahead of and behind a cold
front. The best chances would be on Monday.
&&
.HYDROLOGY...
Any hydro impacts over the weekend appear minimal at this time.
&&
.TIDES/COASTAL FLOODING...
There is a moderate risk of rip currents Thursday and Friday. With a
15-17 kt easterly flow on Thursday and 4-5 ft waves at 6s, there is
potential for an upgrade to a high rip current risk. Regardless, rip
current activity will be enhanced along jetties and groins both
Thursday and Friday with a strong E to W sweep.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...None.
NJ...None.
MARINE...None.-- End Changed Discussion --
&&
$$
SYNOPSIS...JE/JT
NEAR TERM...JE/MET/JT
SHORT TERM...JE
LONG TERM...JT
AVIATION...MET
MARINE...JE/JT
HYDROLOGY...JE/JT
TIDES/COASTAL FLOODING...