191
FXUS61 KOKX 300657
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
257 AM EDT Sun Jun 30 2024

.SYNOPSIS...
A warm front will continue to lift northeast through the area
overnight. A pre-frontal trough will approach and settle nearby
today, followed by a cold front this evening. High pressure
will then build in from the northwest through Tuesday, and push
offshore late Tuesday into Tuesday night. A warm front will
lift to the north on Wednesday. A cold front will then approach
Wednesday night and stall nearby near the area through the end
of next week into the first half of next weekend.

&&

.NEAR TERM /UNTIL 8 AM THIS MORNING/...
A warm front will lift north of the area into early Sunday
morning. There is very little instability, so expect only
showers mainly near the coast.

Should also see some areas of fog and low stratus along the
coast overnight. It will be muggy with lows struggling to fall
out of the 70s.

&&

.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM MONDAY/...
Large scale numerical weather prediction models show a consensus
with mid level height falls continuing this afternoon and
tonight. This will be ahead of an approaching strong shortwave
trough from the eastern Great Lakes through SE Canada. The
height falls appear to occur more rapidly compared to the
previous night.

The models indicate a return of positive vorticity advection
this afternoon into early Sunday evening.

At the surface, a cold front will be approaching from the west,
eventually moving this afternoon and then moving west to east
across the region this afternoon into Sunday evening. The cold
front passes southeast of Long Island late tonight.

The models show 0-6 km bulk shear increases to near 40-50 kt
and potentially above 50 kt as well. This combined with surface
instability as conveyed by CAPE values between 2000 and 4000
J/kg across the region near NYC and locations north and west.
Less CAPE to the east with more marine influence. There will be
potential for strong to severe thunderstorms with damaging winds
and large hail possible. Primary threat would be damaging
winds.

The forcing further is evident from the local region being
relatively closer to the right rear quad of an upper level jet
streak from SE to NE from New England into the Canadian
Maritimes. This will provide for greater divergence aloft.

CAMs show ongoing convection south of Long Island for early this
morning in the 6-10 AM time frame. Then, shower activity sparse
with mainly dry conditions thereafter until around 1-2 PM. From
1-2 PM, convection starts to redevelop north and west of the
area and may start to move into parts of the Lower Hudson
Valley. Between 2-5 PM, the convection develops and solidifies
into a squall line as it moves southeast farther into the local
region, reaching through Southern CT, northeast NJ, Lower Hudson
Valley, NYC into much of Long Island. Convection expected to
linger across much of the area this evening with much of the
activity gradually shifting to more eastern locations. Eastern
Long Island and southeast CT could have some lingering showers
and thunderstorms late tonight.

PW will remain a little above 2 inches into this evening.
Flooding will remain possible with thunderstorms.

Also to note, some indication with max updraft helicity across
parts of the region, mainly across interior. This signals a
potential for rotation within thunderstorms. A brief tornado
cannot be ruled out.

Regarding temperatures, this will be quite dependent on cloud
coverage. Still even with abundant cloud coverage, warm air
advection expected to have much warmer high temperatures
compared to the previous day. Forecast highs are well into the
80s for most locations with values more in the lower 80s along
much of the coastline. Some parts of NYC and northeast NJ are
forecast to reach the lower 90s. Max heat indices can be
expected to be a few degrees above the actual temperature,
keeping the forecast region below heat advisory criteria. The
highest heat indices are forecast to be mainly between 90 and 95
with some 95 to 97 degree heat indices for mainly parts of
northeast NJ.

Late tonight into early Monday, dry conditions expected to
eventually re-establish across the region from NW to SE.
Forecast lows range from the upper 50s to mid 60s.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
The cold front will continue to push offshore Monday morning as the
upper level trough over western and central portions of the
Northeast treks southeast. This will be the focus for some lingering
showers for eastern areas Monday morning and early afternoon. The
high continues to build in for Tuesday and pushes offshore late in
the day Tuesday into Tuesday night. Meanwhile, upper level ridging
over the Great Lakes noses into the Northeast. This allows a warm
front to lift north of the region sometime on Wednesday, and the
associated cold front to start moving through sometime on Thursday,
which then may stall somewhere near the area through the end of the
week.

With high pressure in place, conditions should be dry through
Wednesday as the warm front lifts north too far west to bring any
precipitation. Precipitation is expected with the approaching cold
front and chances for showers and thunderstorms look to continue
through the first half of next weekend.

As for temperatures, they are expected to be seasonable through
Wednesday. With upper level riding nosing in on Thursday, warmer
conditions are forecast, with highs in the upper 80s to lower 90s
away from the coast. Similar readings are expected through Saturday.
Humidity levels will also be on the rise. Prior to Wednesday night,
dew points will generally be in the 50s to around 60. From Wednesday
night onward, dew points rise into the 60s to around 70.

&&

.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
A warm front will continue to lift northeast through the area
overnight. A pre-frontal trough will approach and settle nearby
today, followed by a cold front this evening.

Seeing LIFR cond attm at KISP/KHPN/KGON, with KJFK currently VFR
but right on the edge of those conditions, which should return
there overnight into the AM hours. MVFR at KEWR/KTEB/KSWF should
also expand to KLGA/KBDR overnight.

Diminishing area of light showers moving across attm. Expect dry
cond thereafter until at least midday, then two rounds of tstm
are possible. The first of these with the pre-frontal trough
should impact the Hudson Valley terminals from 17Z-19Z, the NYC
metros from about 18Z-20Z, and out east across Long Island/CT
from 19Z-21Z. The second round with the cold front should occur
from late afternoon into the evening, impacting the NYC metros
from 22Z-23Z until 02Z-03Z, once again about an hour earlier to
the NW and an hour or two later to the E. Stronger cells with
either round could produce strong W-NW winds, but have not yet
mentioned this explicitly in TAF`s.

Outside of tstms, S-SW winds 5-10 kt should become more SW and
increase to 10-15 G20kt by afternoon. After cold fropa this
evening, winds shift NW around or just over 10 kt, with some
terminals gusting to 15-20 kt.

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

KJFK currently VFR, but sitting on the edge of LIFR cond that
could expand back into the terminal airspace overnight into the
AM push. MVFR likely to return to KLGA as well.

Strong wind gusts possible with any tstm directly impacting the
terminals this afternoon into this evening.

OUTLOOK FOR 06Z MONDAY THROUGH THURSDAY...

Late Sunday night: VFR. NW winds G15-20kt.

Monday through Wednesday: VFR.

Thursday: Possible MVFR or lower cond with any late day or
nighttime showers/tstms.

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

&&

.MARINE...
SCA remains on South Shore Bays and ocean into this evening,
with gusts up to 25 kt and ocean seas above 5 ft.

Late day winds in the NY Bight area just E of Sandy Hook could
gust close to 25 kt each afternoon Wed through Fri.

&&

.HYDROLOGY...
Minor flooding probable Sunday afternoon and evening with
thunderstorms. Localized flash flooding cannot be ruled out.
Total rainfall amounts through Sunday evening between 1/2 to 1
inch, with locally higher amounts possible.

Locally heavy rainfall may also be possible Thu night into Fri
with a passing frontal system.

&&

.TIDES/COASTAL FLOODING...
A high rip current risk continues into Sunday with swells of
5-6 ft and 7 second period. The high risk should continue into
Monday morning, but it looks like most beaches will transition
to moderate from late morning onward.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents through this evening for NYZ075-080-081-
     178-179.
NJ...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ345.
     Small Craft Advisory until midnight EDT tonight for ANZ350-353-
     355.

&&

$$