201
FXUS61 KOKX 171125
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
725 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/...
Included patchy fog in the forecast this morning as it remains
possible, particularly in more rural areas with calmer winds.
Otherwise, forecast remains on track with only minor adjustments
to account for the latest observations with respect to
temperature and dew points.

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 /12Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
Offshore high pressure remains in control through the TAF period. VFR. Lingering low stratus currently only affecting KHPN and is expected to improve before or just after 12z. Winds will remain southerly through the TAF period. Wind speeds will increase to 10-15 kt range with some slightly higher wind speeds for NYC terminals. Wind gusts this afternoon into early this evening are expected to be near 20-25 kt. Winds then fall below 10 kt again for tonight. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Start and end timing of gusts could be a few hours off from the TAF. OUTLOOK FOR 12Z TUESDAY THROUGH FRIDAY... Tuesday 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
-- End Changed Discussion --
&& .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...