discussion on 2023-05-12

000
FXUS61 KOKX 121759
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
159 PM EDT Fri May 12 2023

.SYNOPSIS...
A surface trough remains over the area today. A cold front moves
through late Saturday followed by high pressure building in from the
northwest on Sunday. High pressure builds in from the north and west
Sunday night. The high pressure area moves out into the Atlantic
Ocean Monday with a wave of low pressure passing well south of the
local region Monday afternoon into Monday night. A cold front
approaches from the north going into the middle part of next
week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Only minor adjustments were made to temperatures and dewpoints
in the latest update to capture current trends and obs. Isolated
chance POPs were expanded into Middlesex county and far eastern
north and south forks of Long Island. With high pressure to our
south over the Western Atlantic, a warm SW- W flow under slow
building heights aloft will make for an unseasonably warm spring
day across the area.

Temperatures will top out in the low to mid 80s. Across southern
Long Island and southern CT these highs will likely be reached
several hours earlier than usual due to sea breezes. Current
forecast highs look to fall short of records at most climate sites.
LaGuardia looks to have the best chance at tying a record, see the
Climate section below.

A weak mid-level shortwave passes to our north and east this
afternoon and early evening. CAMs continue to show the
potential for isolated showers this afternoon for far eastern
portions of our area. With a few hundred J/kg of SBCAPE, a
thunderstorm can not be ruled out. An isolated thunderstorm
chance has been added for these areas.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
Most of tonight will be dry, but PoPs and sky cover do increase
towards Saturday morning with another shortwave approaching.
Stuck with chance PoPs for southern portions of our area, but
this may trend down in later forecasts as most CAMs show the
shower activity staying farther to our south. It looks like the
better shot at seeing showers could be ahead of the cold front
later Saturday afternoon/evening. Stuck with slight chance given
the expected isolated nature.

With the increase in cloud cover tonight, lows will be well
above normal and record max min temperatures are possible for
Saturday. See the climate section below.

High pressure builds in behind the cold front. With clearing
expected to move from north to south, northern locations will
likely be able to take advantage of decent radiational cooling
conditions and drop into the mid 40s. A sunny Sunday is then
expected, with highs closer to normal under a N-NW flow.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Relative weakness in mid level present in the model guidance to
start the long term as the local region sits between a shortwave
passing offshore and a shortwave to the west for Sunday night. The
shortwave to the west moves south of the local region Monday into
Monday night. Westerly mid level flow then remains going into
midweek with a large upper level low moving southward near the
Canadian Maritimes.

At the surface, high pressure builds in from the north and west on
Sunday night. Dry conditions continue and the northerly flow becomes
light with not too much cloud coverage, allowing for some
radiational cooling. Forecast lows range from the low 40s to low 50s.

High pressure then moves well out into the Atlantic Monday into
Monday night with a wave of low pressure following behind it as
well. This wave of low pressure will be moving well south of the
region. A dry forecast will be maintained. More breezy westerly
winds are forecast Monday into Monday night. Along with some
remaining clouds, the diurnal temperature curve will not be as steep
for this time period. Daytime highs Monday forecast mainly in the
mid 60s to lower 70s will only drop into the upper 40s to mid 50s
Monday night for the lows.

Some warmer air advects in Tuesday with the west to southwest flow
continuing with most locations having forecast highs between 70 and
80. Lows forecast Tuesday night are mainly in the upper 40s to mid
50s. A cold front will be approaching and eventually moving across
the region from the north. Without much moisture source to use with
this front, only have slight chance POPs for rain showers.

Strong high pressure builds into the area Wednesday into
Thursday before moving offshore Thursday night. The remainder of
the forecast is mainly dry with highs getting back into the mid
60s to low 70s range.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --A surface trough will remain over the area while high pressure
remains offshore. A cold front will approach from the north
late tonight and pass through early Sat morning.

VFR, with perhaps slight chance of a sprinkle or shower late
tonight into Saturday morning.

Winds at the NYC metros with the exception of KJFK should be
more westerly than previously forecast, with speeds still
around 10 kt and some gusts 15-18 kt. S flow expected at KJFK,
and should increase close to 15 kt after about 20Z. KLGA should
see a light S sea breeze come in this evening after 00Z.

Gusts abate and winds diminish tonight to SW less than 10 kt.
Cold fropa followed by NW-N flow 5-10 kt.

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

No unscheduled AMD expected attm.

 ...OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...

Saturday afternoon through Monday night: VFR.
Tuesday: VFR. SW-W flow 15G20-25kt.
Wednesday: VFR. NW flow 10-15G20kt.

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

&&

.MARINE...
Sub SCA conditions expected through the weekend under a weak
pressure gradient. There could be a brief period late this
afternoon/early evening of marginal SCA gusts on the ocean waters,
but thinking they will largely be below 25 kt.

Sub-SCA conditions forecast to continue Sunday night. SCA conditions
forecast to return mainly on the eastern ocean but remain below SCA
thresholds elsewhere early next week. Conditions return to below SCA
for all waters by the middle part of the week.

&&

.HYDROLOGY...
There are no hydrologic concerns through next week.

&&

.CLIMATE...
Record Maximum High Temperatures for Friday, May 12th
-----------------------------------------------------
Newark NJ..........92 (1959)
Bridgeport CT......88 (1991)
Central Park NY....93 (1881)
LaGuardia NY.......88 (1991,1948)
Kennedy NY.........89 (1991)
Islip NY...........87 (1991)

Record Maximum Low Temperatures for Saturday, May 13th
-----------------------------------------------------
Central Park........69 (1956)
LaGuardia...........67 (1956)
Kennedy.............64 (1991)
Islip...............60 (1991,1985,1975)
Newark..............68 (1985,1956)
Bridgeport..........59 (1985)

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$
SYNOPSIS...JM/JT
NEAR TERM...BR/JT
SHORT TERM...JT
LONG TERM...JM
AVIATION...BG
MARINE...JM/JT
HYDROLOGY...JM/JT
CLIMATE...