Area Forecast Discussion
Issued by NWS Upton, NY

Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
509
FXUS61 KOKX 172016
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
416 PM EDT Wed Jul 17 2024

.SYNOPSIS...
A cold front approaches this evening and moves through the area
late tonight into early Thursday morning. The front then becomes
nearly stationary Thursday afternoon as high pressure slowly
builds and settles in on Friday. The high will remain in
control through the weekend, with a weak cold frontal passage
possible late Sunday into Monday. A warm front will move through
early next week.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A severe thunderstorm watch remains in effect for the entire
area, including the marine zones, until 800 PM EDT.

A heat advisory remains for much of the area until 800 PM EDT,
as temperatures have peaked into the upper 80s and lower 90s,
with heat indices 95 to 101.

Scattered to line segments of thunderstorms, locally severe
remain possible, with the main threat damaging winds in excess
of 58 MPH. Also a threat of an isolated tornado, and hail to
around 1 inch in diameter, are possible, as the pre frontal
trough moves across the region. A cold front moving into western
upstate New York, and northwestern Pennsylvania will move into
the region late tonight and east of the region by early Thursday
morning. Once the trough moves through, showers and isolated
thunderstorms will be possible until the cold front passes.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
A cold front just to the east of the region early Thursday
morning will become nearly stationary by Thursday afternoon as
an upper trough remains to the west with a near blocking pattern
setting up, and the flow parallels the front. A few showers will
remain possible across the eastern areas early Thursday morning.
A slightly cooler airmass moves into the area, and dew points
are expected to fall through the day, into the upper 50s inland
and lower and mid 60s elsewhere. This drier and cooler airmass
will bring an end to the heat and humidity of the passed several
days.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
No significant changes made to the long term forecast and the
latest NBM was largely used with this update.

High pressure settles over the region Friday and remains in
control this weekend. The front that passes offshore Thursday
will remain south of the region. High temperatures on Friday
will be close to seasonable levels in the middle to upper 80s.
Temperatures rise slightly this weekend with highs a few degrees
warmer in the upper 80s to around 90, warmest in the NYC metro
and NE NJ. Dew points in the lower 60s will prevent heat indices
from rising too much above the actual air temperature.

A weakening cold front may pass across the area late Sunday
into Monday, but will likely not result in anything other than
an isolated shower. At the same time, the aforementioned front
stalled offshore will start to make it`s way back north as a
warm front. This front will return unsettled weather to the area
with chances of showers/thunderstorms mainly Tuesday into next
Wednesday.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
A pre-frontal trough will linger nearby today, followed by a
cold frontal passage late tonight into Thursday morning. The
front will slow down and linger just offshore for daytime
Thursday.

Severe thunderstorm watch now in effect until 8 PM. Storms
already approaching KSWF and over ern PA and NW NJ will also
approach the metro area late this afternoon, with initial
timing 21Z-22Z at the metros and KBDR, 23Z KISP, and 00Z KGON.
TEMPO for most sites now includes strong winds and IFR vsby for
a couple of hours. Mention of tstms for the metros runs into the
evening as there could be a second round from about 00Z-03Z.
Showers with MVFR cond could follow until cold fropa late
tonight, then VFR expected for the AM push.

Wind prior to tstm arrival should be mostly S around 10 kt,
though latest obs do show winds backed to the SE at some of the
metros. Winds following tstms are uncertain and could be erratic
for a few hrs, then settle in on a NW flow just under 10 kt for
the AM push.

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

Confidence medium to high on tstm timing...AMD possible if fine
tuning is needed. Confidence low on winds and MVFR flight cat
following tstms overnight.

OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY...

VFR.

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

&&

.MARINE...
A severe thunderstorm watch remains in effect for all the
marine forecast zones until 800 PM EDT.

A cold front will be passing through the waters late tonight
into Thursday morning, then become nearly stationary Thursday
afternoon. Winds become W to NW behind the front and ocean
seas will be slowly subsiding. A SCA remains on the ocean
waters into Thursday morning on the waters west of Fire Island
Inlet, and through Thursday to the east. Seas may remain
elevated mainly east of Moriches Inlet into Thursday evening,
and the SCA may need to be extended.

Once ocean seas subside, winds and seas will remain below
advisory levels on all the waters into early next week.

&&

.HYDROLOGY...
Any strong thunderstorms through this evening will be capable
of producing localized heavy rain resulting in a limited risk of
flash flooding, mainly of the localized urban and poor drainage
variety. The Weather Prediction Center has placed the area in a
marginal risk of excessive rainfall through early tonight.

No hydrologic impacts are anticipated Thursday into early next
week.

&&

.TIDES/COASTAL FLOODING...
A high risk of rip currents will remain through Thursday with
seas remaining elevated on a SE swell of up to 8 seconds.

&&

.CLIMATE...
Daily record high minimum temperatures for today, July 17:

 ...WED JUL 17...

Newark:        80/1968
Bridgeport:    77/1968
Central Park:  82/1870
LaGuardia:     79/1999
Kennedy:       79/2013*
Islip:         75/2021*

* = also in previous years

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert until 11 PM EDT this evening for CTZ005-006-
     009-010.
     Heat Advisory until 8 PM EDT this evening for CTZ005>011.
NY...Air Quality Alert until 11 PM EDT this evening for NYZ067>075-
     176-178.
     Heat Advisory until 8 PM EDT this evening for NYZ067>075-
     078>080-176>179.
     High Risk for Rip Currents through Thursday evening for NYZ075-080-
     081-178-179.
NJ...Air Quality Alert until 11 PM EDT this evening for NJZ002-004-
     006-103>108.
     Heat Advisory until 8 PM EDT this evening for NJZ002-004-006-
     103>108.
MARINE...Small Craft Advisory until 6 PM EDT Thursday for ANZ350.
     Small Craft Advisory until 6 PM EDT Thursday for ANZ353.
     Small Craft Advisory until noon EDT Thursday for ANZ355.

&&

$$

SYNOPSIS...DS/MET
NEAR TERM...JE/MET
SHORT TERM...MET
LONG TERM...DS
AVIATION...BG
MARINE...DS/MET
HYDROLOGY...DS/MET
TIDES/COASTAL FLOODING...
CLIMATE...