227
FXUS61 KOKX 160951
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
551 AM EDT Sun Jun 16 2024

.SYNOPSIS...
High pressure moves across the area today and stays offshore while
remaining in control through most of the week. The high shifts
south off the Mid Atlantic coast at the end of the week into the
weekend as disturbances pass to the north Friday and Saturday.

&&

.NEAR TERM /THROUGH TONIGHT/...
The forecast is on track this morning. Only minor adjustments
were made to capture the current temperature trend.

High pressure is positioned over the area today gradually
sliding offshore through the evening and into tonight. Mostly
clear skies with comfortable conditions are expected today with
a light east wind gradually shifting to the southeast and south
this afternoon. Highs will be in the middle to upper 70s for
much of the area.

Low level moisture gradually increases tonight with a southerly
flow advecting higher dew points into the area as the high
shifts into the Western Atlantic. This may result in the
development of some low stratus for parts of the Lower Hudson
Valley or along the immediate coast but confidence in occurrence
and coverage is low. Lows will be in the upper 50s for interior
and eastern portions of the area with the NYC metro only falling
into the low to middle 60s.

&&

.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
The large scale ridge begins to build overhead and strengthen
into Monday with surface high pressure remaining offshore. A
continued south to southwest flow will continue to allow for
increased moisture advection along with the advection of warmer
air. Highs on Monday will begin to increase a bit with western
areas climbing into the upper 80s to possibly near 90. Long
Island and Southern CT will be in the low to middle 80s. Mostly
clear skies and dry conditions continue. Lows Monday night will
be in the middle 60s to near 70 near the NYC metro.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
**Key Points**

* A long duration heat wave is expected Tuesday through next
  Saturday.

* The combination of the heat and humidity will produce heat index
  values of 95 to potentially around 105 during this time.

* Not much relief at night as overnight lows will be in the upper
  60s to the mid 70s, with dew points remaining in the 60s.

By Tuesday, surface high pressure will be offshore to our east and
remain in control through most of the week resulting in a persistent
S/SW flow. Aloft, an upper level ridge continues to build over the
northeast US. Latest global guidance continues to show 500mb heights
peaking on Thursday around 598dam to 600dam. To give an idea of
how anomalous this is, the highest 500mb height the OKX
sounding has ever recorded is 598dam per the SPC Sounding
Climatology Page and the highest ever recorded in June is
597dam. This set up will bring long duration heat and humidity
to the area starting Tuesday, likely peaking Thursday and
potentially continuing into Saturday. Heat Advisories will
likely be needed with this event, with the potential for
Excessive Heat Watches and Warnings.

Forecast highs were derived by blending the previous forecast with
the NBM and NBM 50th percentile. Overall this nudged up highs for
most areas from the previous forecast. Highs in the 90s with
dewpoints in the 60s to low 70s will result in heat index values
from 95 to about 105. Given the S/SW flow, the areas that will see
the highest temperatures will be northeast NJ, the Lower Hudson
Valley and interior CT. The flow will keep Long Island, coastal CT
and even parts of NYC a bit lower, but still likely Advisory
criteria for at least some days. Along with hot and humid
temperatures during the daylight hours, overnight lows will not give
much relief as they will remain in the upper 60s to mid 70s. The
best chance to break any record highs looks to be Thursday. There
will also likely be record high low temperatures on Thursday as well.

With the intense heat and high humidity it is important to take
precautions to protect one`s health, particularly those without
effective cooling and/or adequate hydration. The onset of the heat
will be occurring as the transition from spring to summer occurs,
with the solstice Thursday, June 20th at 446 PM EDT.

The upper level ridge begins to flatten Thursday and the flow
becomes zonal Friday. At the same time, high pressure gets
suppressed farther south. With the approach of a surface trough,
chances of showers/thunderstorms return Friday and continue through
the weekend.

&&

.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
High pressure builds across the area this morning before moving
offshore this afternoon and evening.

VFR conditions are expected through the TAF period.

Winds become more NE-E early this morning, followed by winds
becoming more SE in the afternoon. Wind speeds will be generally
near 8-10 kt. Low confidence in the development of low stratus
late tonight and into early Monday.

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

KTEB may have more variable wind direction 12-16Z.

OUTLOOK FOR 09Z MONDAY THROUGH THURSDAY...

Sunday night through Monday morning...Mainly VFR. A chance for
some MVFR to IFR stratus late Sunday night into early Monday
morning.

Monday afternoon through Thursday: VFR.

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

&&

.MARINE...
With high pressure remaining in control, sub SCA conditions are
expected on all waters through the end of the week.

&&

.HYDROLOGY...
There are no hydrologic concerns through the end of next week.

&&

.TIDES/COASTAL FLOODING...
The moderate risk of rip currents continues both Sunday and
Monday.

&&

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

&&

$$

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