Area Forecast Discussion
Issued by NWS Upton, NY

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252
FXUS61 KOKX 211448
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1048 AM EDT Sat Sep 21 2024

.SYNOPSIS...
Low pressure will remain east of Long Island today, then head
slowly farther out to sea into early next week. Meanwhile, high
pressure will nose in from the northeast this weekend and remain
in control through at least early Tuesday. A frontal system may
then approach and move across the area during the middle to
late week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Low pressure will remain east of the region today as high
pressure slowly starts to nose in from the north late in the
day. There will be a continued slight chance to chance of
showers across the far eastern sections of the CWA. Light radar
returns are just making it into Middlesex CT and just past the
LI forks from the east. This activity will likely only lead to
trace amounts of rain. Further east measurable rain is more
likely. In addition, the tight pressure gradient will keep a
gusty N-NE wind with 20-25mph gusts likely. Otherwise, partly to
mostly cloudy skies can be expected today, except further east
where clouds can be expected. Temperatures today will vary from
the upper 70s to near 80 across the NYC/NJ metro area, to the
middle and upper 60s across the far eastern portions of CT and
Long Island.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
As high pressure continues to slowly nose in from the north
during the short term period, the offshore low slowly slides
further eastward. Aloft, heights start to rise, especially the
second half of Sunday, as an upper level ridge builds in. This
pattern will lead to dry and mostly sunny conditions Sunday.

Continued cold air advection in a N-NE flow will lead to low
temperatures tonight in the in the 50s for much of the area,
with some near 60 degree readings across NYC. Sunday, Highs will
only reach the lower and middle 70s area wide.

The dry and cool conditions continue into Sunday night as lows
fall into the upper 40s and 50s.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Key Points:

* Dry into much of Tuesday.

* Possible showers mid to late week with an approaching frontal
  system.

* Temperatures will likely end up slightly below normal starting
  Monday.

Little change in the long term. High pressure nosing down from
the Northeast remains over the region through at least Monday,
leading to a continued period of dry conditions. With low
pressure heading away from the area, the pressure gradient will
lower and allow winds to gradually decrease. Stuck fairly close
to the NBM during this time period.

There is some disagreement for what happens mid to late week
with the approach and passing of a frontal system. Any unsettled
weather from this system will depend on strength of surface
high pressure and evolution of the approaching upper level
trough. Continued to go lower than NBM with PoPs based on the
latest GFS keeping the surface high locked in over the
northeast. For now, will keep POPs at chance and not go likely
at this time. Otherwise, the remainder of the forecast was close
to the NBM. With the wetter/cloudier solution temperatures will
likely be just below normal much of the week. If guidance
starts trending closer to the latest GFS, a drier/more sun
solution may end up with slightly warmer temperatures.

&&

.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
Low pressure will remain east of Long Island today.

VFR to start however some MVFR or lower conditions are expected
mainly across the far eastern terminals today. The best chances
will be KGON along with kISP and KBDR. Otherwise expecting a
mainly VFR Saturday.

While showers continue to struggle with a westward push, it does
appear that KGON could see some rain, especially this morning.
Will cover this with a TEMPO group. Lower confidence of showers
continuing into the afternoon.

N-NE 08-15 kt today for the NYC terminals. Further east, winds
may be slightly stronger with gusts into the 20-26kt range. Can
not rule out an occasional gust in NYC, however confidence too
low to include in the TAF.

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

Can not rule out an occasional gust to 20kt during the early to
mid afternoon.

OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY...

Sunday: VFR. NE winds G15-20 kt possible, highest east.

Monday: VFR.

Tuesday and Wednesday: Mainly VFR, with pockets of MVFR
possible.

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

&&

.MARINE...
SCA has been extended into Sunday night for the ocean waters,
and through midnight for the far eastern Sound.
Peconic/Gardiners Bays was also extended to include all of
today. Winds across the eastern waters should gust to 25-30 kt,
with ocean seas on the outer waters building from 6-7 ft to 8-10
ft today. Ocean seas should subside somewhat tonight back to
6-7 ft.

With the exception of the far eastern ocean waters, wind gusts
will likely be below 25 kt on Sunday. Ocean seas will however
remain elevated through at least the middle of the week, and
extensions to the current SCA are likely.

&&

.HYDROLOGY...
There are no hydrologic issues through the middle of next week.

&&

.TIDES/COASTAL FLOODING...
Coastal flooding will continue into Sunday for much of the for
much of the area and possibly into early next week for the south
shore back bays of western LI due to offshore low pressure and
an easterly swell propagating away from it at a time of high
astronomical tides. A slight increase in surge is expected with
this morning/early afternoon tide, which will help compensate
for a downward trend in astronomical tides. Forecast surge
varies from near 1 to near 2 ft, highest along the south shore
bays of Long Island and parts of western Long Island Sound. Both
surge and astronomical tide levels should begin decreasing
Sunday into early next week.

Minor to moderate coastal flooding is expected with the
morning/early afternoon high tide today. The moderate coastal
flooding will occur across the most vulnerable locations in the
south shore back bays with localized moderate not out of the
question for locations adjacent to western LI Sound and lower NY
Harbor. No changes were made to the coastal flood warnings and
advisories for this tide cycle. Minor coastal flooding is
expected with tonight`s high tide across the south shore back
bays and a coastal flood advisory has been issued for this
cycle. A statement has been posted for for western Great South
Bay, lower NY Harbor and western LI Sound in coastal Fairfield
and coastal Westchester where minor benchmarks may just be
touched.

Have held off on any headlines for midday Sunday high tide.
Guidance has been trending slightly lower the last 24 hours with
any moderate flooding looking isolated to the south shore back
bays. Otherwise, an advisory will likely be needed for most
other areas for minor flooding.

The high rip current risk continues through Sunday evening due
to a prolonged period of easterly swells.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Coastal Flood Advisory until 4 PM EDT this afternoon for
     CTZ009-010.
     Coastal Flood Advisory until 4 PM EDT this afternoon for
     CTZ011-012.
NY...Coastal Flood Advisory until 4 PM EDT this afternoon for
     NYZ071-073-078-176-177.
     Coastal Flood Advisory until 4 PM EDT this afternoon for
     NYZ079>081.
     Coastal Flood Advisory until 2 PM EDT this afternoon for
     NYZ072-074-075.
     High Risk for Rip Currents through Sunday afternoon for NYZ075-080-
     081-178-179.
     Coastal Flood Warning until 3 PM EDT this afternoon for NYZ178-
     179.
     Coastal Flood Advisory from 10 PM this evening to 2 AM EDT
     Sunday for NYZ178-179.
NJ...Coastal Flood Advisory until 2 PM EDT this afternoon for
     NJZ006-106-108.
MARINE...Small Craft Advisory until midnight EDT tonight for ANZ332.
     Small Craft Advisory until 6 PM EDT this evening for ANZ340.
     Small Craft Advisory until 6 AM EDT Monday for ANZ350-353-355.

&&

$$

SYNOPSIS...BC
NEAR TERM...BC/JT
SHORT TERM...BC
LONG TERM...BC
AVIATION...BC/DW
MARINE...BC
HYDROLOGY...BC
TIDES/COASTAL FLOODING...