353
FXUS61 KOKX 170810
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
410 AM EDT Mon Jun 17 2024

.SYNOPSIS...
High pressure remains centered off the mid Atlantic coast
through Thursday before slowly weakening and drifting east. A
surface trough lingers over the area for the end of the week
through the first half of the weekend. A low pressure system
approaches on Sunday.

&&

.NEAR TERM /THROUGH TONIGHT/...
High pressure offshore is continuing to provide dry conditions
under a mostly clear sky. Some lower stratus have developed over
NE NJ and moved into portions of the Lower Hudson Valley due to
a light onshore flow enhancing low level moisture in the area.
Otherwise, some high cirrus are streaming through the area from
the northwest.

Temperatures will be on the increase today as an upper level
ridge builds over the East Coast. a mainly southerly component
to the wind will allow an increase in dew points as well today.
Highs will be in the 80s with some locations for the Lower
Hudson Valley and NE NJ approaching 90. Eastern locations may
only rise into the upper 70s.

Continued moisture advection into the area will prevent low
temperatures from dropping too much, despite mostly clear skies
expected. Lows will be in the middle 60s to lower 70s near the
NYC metro.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The strong ridge continues to strengthen over the area on
Tuesday and Wednesday, allowing for the beginning of a heat
wave in much of the area. High temperatures on Tuesday will be
in the low to middle 90s for much of NE NJ, the Lower Hudson
Valley and portions of interior southern CT. This heat combined
with dew points in the upper 60s will allow for heat index
values in the 95-100 degree range for the western half of the
area. After collaboration with the surround offices and
anticipation of the extended heat through the week, opted to
include Northern Fairfield and Northern New Haven counties in
Southern Connecticut to the existing heat advisory for Tuesday.

Heat advisories will likely need to be expanded to other
counties in interior southern Connecticut and perhaps closer to
the coast. A southerly flow is providing a sheltering effect
from the heat for the NYC metro, Long Island, and the immediate
Connecticut coastline so details on the exact extent of the heat
in these locations is a bit more uncertain. It`s important to
note however that although these locations may not result in
heat index values high enough to warrant an advisory, highs in
the middle to upper 80s and with heat index values near 90 will
still necessitate caution when exposed to the heat.

Lows Tuesday night and Wednesday night will be only in the upper
60s to low 70s for much of the area.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
**Key Points**

* The heat wave is expected to continue in the long term period,
  peaking Thursday and Friday and continuing through at least
  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.

The upper level ridge continues to slowly flatten on Thursday in
response to an upper level trough moving through northern Canada.
Latest guidance continues to show highly anomalous 500mb heights
around 598dam to 599dam. 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. At the surface, high pressure centered
offshore to our southeast will slowly weaken and drift east Thursday
as a surface trough lingers over the area. This pattern will
continue the heat and humidity across the area. The heat wave will
likely peak Thursday and Friday and could continue until at least
Saturday. Current Advisories will likely be expanded to include more
counties and extended in time. Excessive Heat Watches/Warnings can
not be completely ruled out either at this time. There is potential
for a few climate sites to near or break high temperatures records
on Thursday and Friday. Also, with overnight temperatures remaining
elevated a few locations may set record high minimum temperatures
Thursday, and possibly Saturday.

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.

With the upper level ridge flattening for the end of the week and
weekend, some weak disturbances track near or just north of the
area. A low pressure system then looks to approach the area on
Sunday. Slight chance to chance of showers/thunderstorms starts
Friday and continues through the weekend.

&&

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
Offshore high pressure remains in control through the TAF period.

Mainly VFR conditions are expected but there is a chance for some
MVFR/IFR stratus through early this morning, mainly between 06Z and
12Z. This is indicated by a TEMPO group in the TAF. Confidence is
low to moderate on the stratus occurrence.

Winds will become more southerly tonight and remain southerly
through the rest of the TAF period. Wind speeds tonight will be near
5-10 kt and then increase Monday to 10-15 kt range with some
slightly higher wind speeds for NYC terminals. Wind gusts Monday
afternoon into early Monday evening are expected to be near 20-25 kt.

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

Timing of stratus, if it occurs, could be a few hours off from TAF.
Confidence is low to moderate.

Timing of gusts on Monday could be a few hours off from TAF.

OUTLOOK FOR 06Z TUESDAY THROUGH FRIDAY...

Monday night through Friday: Mainly VFR. S-SW wind gusts 15-20 kt
afternoon into early evening for Tuesday and Wednesday.

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

&&

.MARINE...
With high pressure largely in control, sub Small Craft Advisory
conditions are expected through at least the first half of the
weekend.

&&

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

&&

.TIDES/COASTAL FLOODING...
A moderate risk of rip currents at the ocean beaches continues
through Tuesday with a southerly flow, and southeast to south swells.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Heat Advisory from noon Tuesday to 8 PM EDT Wednesday for
     CTZ005-006.
NY...Heat Advisory from noon Tuesday to 8 PM EDT Wednesday for
     NYZ067>070.
NJ...Heat Advisory from noon Tuesday to 8 PM EDT Wednesday for
     NJZ002-004-006-103>108.
MARINE...None.

&&

$$

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