401
FXUS61 KOKX 281120
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
720 AM EDT Fri Jun 28 2024
.SYNOPSIS...
High pressure builds across the area today, the pushes offshore
tonight. A warm front will then approach on Saturday and lift
north into the area Saturday night, followed by a cold front on
Sunday. High pressure then returns on Monday and lasts into the
middle of next week. Another frontal system may approach next
Thursday.
&&
.NEAR TERM /THROUGH TONIGHT/...
Minor update this morning to temps and dewpoints to better
reflect current observation trends. Otherwise, forecast remains
on track.
High pressure builds overhead, resulting in sunny skies across
the area today with temperatures in the mid 70s to near 80.
Tonight that area of high pressure will move offshore and low
pressure will begin to track across the Great Lakes.
Temperatures tonight will be upper 50s to mid 60s.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
On Saturday the warm front associated with the low will begin to
lift north through the region, allowing for a much warmer and very
humid air mass to usher into the region. There is the potential
for locally heavy rainfall along with some scattered
thunderstorms Saturday evening/night. The Storm Prediction
Center already has parts of our area west of the NYC Metro in a
marginal risk for severe weather for Saturday.
High temperatures on Saturday will be in the 70s to lower 80s and
lows in the upper 60s to lower 70s Saturday night. It will be muggy
as dewpoints increase into the upper 60s to lower 70s.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
*Key Points*
*A pre-frontal trough followed by a cold front will bring continued
potential for showers and thunderstorms on Sunday.
*Sunday will be warm and humid with heat indices potentially
reaching around 90 for most with mid 90s in NE NJ.
*High pressure brings less humid air Monday and should remain in
place into Tuesday. Temperatures likely end up a few degrees below
normal Monday and then near normal on Tuesday.
*Temperatures continue to warm Wednesday into Thursday ahead of the
next potential frontal system.
A shortwave and its associated cold front approach on Sunday.
Showers and a few thunderstorms could be ongoing Sunday morning with
the pre-frontal trough. The actual cold front likely does not move
through until the afternoon and evening, which may bring with it
another round of showers and thunderstorms. Precipitable waters
average around 2.00 inches, so any shower or thunderstorm could
produce locally heavy downpours. Minor urban flooding appears to be
the main threat, but a localized flash flood occurrence cannot be
completely ruled out. Effective shear may increase in the afternoon
to 30-35 kt with 1500-2000 J/kg. SPC has placed the area in a
slight risk for severe thunderstorms and CSU Machine-Learning
Probabilities (MLP) highlight a low chance for severe
thunderstorms with damaging winds. This may be dependent on how
the atmosphere recovers from any morning shower/storm activity
with the pre- frontal trough. The CAMs should begin to resolve
this potential in the next 24-36 hours.
Highs on Sunday should reach the upper 80s to low 90s for NYC metro,
NE NJ, and Lower Hudson Valley with lower to middle 80s in S CT and
Long Island. These temperatures will combine with dew points in the
upper 60s to lower 70s making it feel like it is around 90 for most
with mid 90s in NE NJ. The passage of the cold front will usher in
lower dew points and cool temperatures into the lower to middle 60s.
The upper trough will swing through the region late Sunday night
into Monday and will be followed by ridging into the middle of the
week. Surface high pressure starts to build in from the Great Lakes
on Monday. The high then settles overhead Tuesday before shifting
south and east into Wednesday. The latest modeling indicates a
flatter shortwave ridging around the periphery of the ridge, which
may help lower heights aloft. This may be able to bring a weaker
frontal system towards the area by next Thursday. For now will cap
PoPs off at slight chance given the flat signal being depicted by
the deterministic and ensemble means.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
High pressure will remain in control through the taf period.
Mainly VFR. MVFR ceilings are possible early Saturday morning.
NE winds under 10 kt this morning will become S-SE around 10 kt
this afternoon with sea breezes. SE winds diminish after 00z
Saturday.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of seabreeze this afternoon may be off by 1-2 hours.
OUTLOOK FOR 12Z SATURDAY THROUGH TUESDAY...
Saturday: MVFR possible in the morning. Chance of showers in the
afternoon, mainly west of NYC terminals.
Saturday Night: MVFR or IFR possible in showers and thunderstorms.
Sunday: MVFR or lower possible with showers and thunderstorms.
Monday and Tuesday: VFR.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Below SCA conditions today as high pressure builds overhead. SCA
conditions look increasingly likely on the ocean and possibly the
south shore bays for Saturday night as SW flow increases, with gusts
up to 25 kt and seas peaking at 5-6 ft late Saturday night.
SCA gusts around 25 kt likely continue on Sunday on the ocean and
potentially the South Shore Bays. These winds will weaken below SCA
levels in the afternoon and evening as a cold front works across the
waters. Ocean seas should be around 5-6 ft on Sunday before
subsiding below 5 ft Sunday night. A relatively weak pressure
gradient early next week should then lead to conditions below SCA
levels.
&&
.HYDROLOGY...
Rainfall amounts between 0.75 to 1.20 inches are expected
Saturday afternoon through Sunday afternoon with locally higher
amounts possible. Minor poor drainage/urban flooding will be
possible. Flash flooding cannot be ruled out, but with the
forward speed of showers and probably a lack of training cells,
overall chances for flash flooding appear to be low.
&&
.TIDES/COASTAL FLOODING...
The rip current risk for today will range from low to moderate.
As for Saturday, the risk will be mostly moderate, but a high
risk is anticipated for the ocean beaches of Brooklyn and Queens
as well as eastern Suffolk County.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...DS
AVIATION...DS
MARINE...20/DS
HYDROLOGY...20/DS
TIDES/COASTAL FLOODING...