000
FXUS61 KOKX 051144
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
744 AM EDT Tue Sep 5 2023
.SYNOPSIS...
High pressure remains in control through Wednesday. The high
begins to weaken Wednesday night into Thursday. A slow moving
frontal system will impact the area Thursday night through the
weekend. The associated cold front passes through late Sunday
night into Monday.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
Forecast this morning remains on track with just a few minor
adjustments to reflect current observations.
Otherwise, an upper level ridge will remain over the area
through mid- week, resulting in above normal temperatures.
Heat advisories will remain in effect today and Wednesday for
NYC and portions of NE NJ and the Lower Hudson Valley. Expect
heat index values to reach 95 both days in these areas. Isolated
heat index values of 95 may be reached across other areas of
the Lower Hudson Valley and in CT, but they will not be
widespread enough to warrant heat headlines. If temperatures or
dew points end up being slightly warmer than forecast, can not
rule out an expansion of the heat advisory.
Otherwise, generally dry and sunny conditions are expected.
The warm and muggy conditions continue tonight, with lows only
falling into the upper 60s and 70s.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/...
The upper level ridge starts to weaken and slide east Wednesday
night into Thursday. Despite the ridge starting to weaken,
Wednesday night will remain warm and muggy and it remains likely
that heat advisories seem likely on Thursday. Heat index values
are likely to reach 95 in NYC and the upper 90s across a good
portion of NE NJ and the Lower Hudson Valley. In addition, there
seems to be a decent chance we see more widespread 95 heat
index values across CT. The main question will we see widespread
heat index values of 95 in CT on Wednesday to reach the 2 day
criteria for a heat advisory. This will have to be monitored.
With the ridge starting to weaken and slide east, the morning
will start off cloudy, however a cold front will slowly start to
approach from the west. This should result an increase in cloud
cover during the second half of the day. Can not rule out a few
showers or thunderstorms during the afternoon.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
A slow moving upper trough will send a frontal system toward
the area for the end of the week into the weekend. The guidance
continues to trend slower with the actual cold frontal passage
which is now expected Monday morning. That being said, there is
complex interaction between shortwave energy in the northern
branch of the polar jet and a cutoff low over the Great Lakes
into the Ohio Valley. This will impact the progression of the
system. The GDPS (Canadian) is all together very different than
the 00Z GFS and ECMWF, where it shears out the upper low to the
NE sending the cold front through the area Saturday night with a
frontal wave to impact the area on Monday. However, a consensus
approach will keep the area in a southerly flow with warm,
humid conditions and chances of showers and thunderstorms from
Thursday night all the way through the weekend. This will mainly
be warm sector conveyor belt rains with the potential for bouts
of heavy rainfall.
As for temperatures, Friday looks to be the warmest day with
readings in the 80s to even close to 90 for the NJ metro. This
is about 5 to 8 degrees above normal. Thereafter, clouds,
onshore flow and chances of rain should produce highs closer to
normal. However, high humidity will make feel less comfortable.
Lows will also be above normal during this time, mainly in the
lower 70s.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
High pressure will remain in control through midweek with
thermal troughs setting up across the area each afternoon.
VFR. A light northerly flow of less than 10kt will feature
seabreeze development as early as 14-15Z at the CT terminals
14-15Z, but not until afternoon for the remaining coastal
terminals. In fact, there is some uncertainty as to whether it
even makes it to KLGA, KTEB, and KEWR, forecast to arrive in the
21-23Z timeframe. KLGA will likely stay with NE flow off the
East River for much of the day. Winds Tuesday night will once
again become light and variable or light northerly.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of afternoon seabreeze may vary by 1-2 hours. There is
chance it does not make it to KLGA, KEWR, and KTEB.
OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY...
Wednesday: VFR.
Thursday: Mainly VFR. Chance of late afternoon/evening showers
and thunderstorms for the NYC and Lower Hudson Valley terminals.
A slight chance elsewhere.
Friday through Saturday: MVFR possible at times in round of
showers and thunderstorms. S wind gusts 15-20 kt Friday.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Ocean seas generally remain around 3 ft through mid week, however,
an ESE swell from offshore low pressure nearing the Canadian
Maritimes should increase seas to around 4 ft today.
High pressure begins to weaken Wednesday night into Thursday as a
slow moving frontal system approaches from the west Friday into
Saturday, preceded by southerly flow. However, both winds and
seas during this time are forecast to remain below SCA.
&&
.HYDROLOGY...
No hydrologic impacts are expected through Thursday.
There is the potential for 1 to 2 inches with locally higher amounts
of rainfall from Thursday night through the weekend as a slow moving
frontal system approaches from the west. There is still too much
uncertainty with the timing and areal extent of the rainfall.
&&
.TIDES/COASTAL FLOODING...
Long period ESE swells of around 3ft and 9-11s continue today, with
a moderate rip current risk at the ocean beaches. While these swells
begin to diminish on Wednesday, a moderate risk remains for the
Nassau and Suffolk beaches, with a low risk at the New York City
beaches.
&&
.CLIMATE...
Some daily record highs could be tied or broken over the next
couple of days. The record highs for these dates are below.
Daily Record High Temperatures...
Sep 5 Sep 6 Sep 7
Central Park..94 (1985)..97 (1881)..101(1881)
LaGuardia.....93 (1985)..96 (2018)..90 (2015)
JFK...........94 (1961)..92 (1985)..93 (1983)
Islip.........90 (1985)..90 (1985)..92 (1998)
Newark........94 (1985)..98 (2018)..95 (2015)
Bridgeport....91 (1961)..92 (2018)..91 (1983)
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Heat Advisory from 11 AM this morning to 8 PM EDT Wednesday
for NYZ067-069-071>075-176-178.
NJ...Heat Advisory until 8 PM EDT Wednesday for NJZ004-006-103>108.
MARINE...None.
&&
$$
SYNOPSIS...BC/DW
NEAR TERM...BC
SHORT TERM...BC
LONG TERM...DW
AVIATION...DW
MARINE...BC/DW
HYDROLOGY...BC/DW
TIDES/COASTAL FLOODING...
CLIMATE...