Area Forecast Discussion
Issued by NWS Upton, NY

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820
FXUS61 KOKX 152318
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
718 PM EDT Mon Jul 15 2024

.SYNOPSIS...
A weak surface trough will be in place through Tuesday as upper
level disturbances move across. A cold front will approach
from the west on Wednesday, and move through late Wednesday
night into Thursday morning. High pressure will then follow for
late week, and should remain nearby into the upcoming weekend.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Earlier round of convection across LoHud and SW CT has
dissipated with attention turning to a line of storms across NE
PA and upstate NY. This line likely will pass over NW interior,
potentially Orange into Putnam counties. The HRRR has been
hinting at an extension of the line down towards the NYC metro
towards 9-11pm, but confidence not high on its occurrence.

The severe weather threat appears limited to the LoHud where
there is slightly higher CAPE and stronger flow with bulk shear
closer to 30 kt. SPC slight risk clips western Orange, but the
bulk of the severe threat should remain to our NW.

Low temps will be near 80 in NYC, and in the 70s elsewhere.
Some patchy fog may be possible late across areas impacted by
earlier tstms.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Heat advy continues into Tue for most of the area. Temps should
be a tad warmer but dewpoints a little lower, and this should
yield heat index values similar to those of today. There is a
chance for afternoon/evening tstms as a mid level shortwave
trough moves through. SPC slight risk includes areas NW of NYC,
with a marginal risk for the rest of the CWA, as these will be
ample instability and vertical shear to support organized cells
and line segments capable of producing strong wind gusts.

Another very warm/humid night expected for Tue night, with lows
again near 80 in NYC and in the mid/upper 70s most elsewhere.

Extended heat advy into Wed for areas with fcst high temps near
or above 90 and heat index values 95 or more (most of wrn
sections of Long Island/S CT on west). Uncertainty on meeting
criteria is higher for areas to the east, where high temps will
only be in the mid/upper 80s but where dewpoints could be
higher.

Another round of strong to locally severe convection expected
for Wed afternoon and high ahead of the approaching cold front.
Front should enter the area late at night, with low temps from
the upper 60s to mid 70s.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
The main story for the long term will be relief from the high
heat and humidity that currently persists over the region.

Key Points:

* A cold front will continue working offshore on Thursday. A few
  showers, possibly a thunderstorm may linger nearby in the
  morning with dry conditions becoming likely in the afternoon
  and evening.

* Daytime temperatures will return to near seasonable levels
  Thursday and Friday with dew points falling into the lower and
  middle 60s, potentially upper 50s in spots.

* A slight moderating temperature trend is possible for the
  upcoming weekend, but highs will still be in the middle to
  upper 80s with dew points in the 60s.

* Mainly dry conditions should persist into the upcoming
  weekend.

Upper level trough will continue over the region on Thursday
with the cold front pushing offshore. The deep moisture axis
and main area of forcing follows, but there could be some
lingering showers in the morning, especially closer to the
coast. A thunderstorm is possible, but instability will be
diminishing as the front pushes further offshore. Model trends
continue supporting the end of any showers Thursday afternoon
and have trended PoPs lower than the latest deterministic NBM.

The upper trough axis will likely swing across the area Thursday
night into Friday morning. Broad troughing will then persist
aloft into the start of the weekend, with a more amplified
trough passage late in the weekend. The main uncertainty will be
how much moisture will be able to return to the region. Forcing
continues to look weak, but there is a signal for a weak
surface trough or front nearby which could be a mechanism for
convection. The deepest moisture and more organized forcing
stays largely north. Will continue to keep the forecast dry
through the weekend/next Monday, which is in line with the
latest model consensus.

&&

.AVIATION /23Z MONDAY THROUGH SATURDAY/...
A weak surface trough remains in the vicinity through the TAF
period.

A line of showers/thunderstorms may impact Lower Hudson Valley
terminals this evening, potentially extending towards the NYC
metro 02z to 05z. This cluster will be weakening, but
confidence in thunder is high enough to have a TEMPO in the TAF.

Winds mostly SW/S, increasing to around 10-15kt today. Winds lower
to about 5-10kt overnight and then increase again to 10-15kt Tuesday.

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

Occasional gusts to 20kt possible.

Chance for showers/thunderstorms later this evening around 03z
to 05z and have converted PROB30 to a TEMPO.

OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...

Tuesday Afternoon: A chance of evening showers and
thunderstorms and MVFR, mainly from NYC metro on NW. SW wind
gusts 15-20 kt afternoon into early evening.

Wednesday: VFR to start. MVFR or lower in showers and
thunderstorms late afternoon into the evening, with a chance
of showers and thunderstorms late at night.

Thursday: Mainly VFR. Chance of showers and thunderstorms.

Friday and Saturday: VFR.

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

&&

.MARINE...
A period of SCA conditions is possible, mainly on the ocean,
Tuesday night into Wednesday night with increased southerly flow
ahead of an approaching cold front. Lingering 5-6 ft seas are
possible on Thursday before seas subside into the end of the
week.

&&

.HYDROLOGY...
With a humid air mass in place, any thunderstorms that develop
through Wed night will have the potential to produce downpours
capable of causing at least minor urban and poor drainage
flooding.

No hydrologic impacts are anticipated Thursday through the upcoming
weekend.

&&

.TIDES/COASTAL FLOODING...
There is a moderate rip current risk on the ocean beaches into this
evening and then again on Tuesday due to 3-4 ft S swell of 6-8s
and S winds 10-15 kt. Seas increase on Wednesday to 5 ft which
supports a high rip current risk.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Heat Advisory from 10 PM Tuesday to 9 PM EDT Wednesday for
     CTZ005-009.
     Heat Advisory until 10 PM EDT Tuesday for CTZ006>008-010-011.
NY...Heat Advisory from 10 PM Tuesday to 9 PM EDT Wednesday for
     NYZ067>071-078-177.
     Heat Advisory until 10 PM EDT Tuesday for NYZ079-080-179.
     Heat Advisory until 9 PM EDT Wednesday for NYZ072>075-176-178.
NJ...Heat Advisory from 10 PM Tuesday to 9 PM EDT Wednesday for
     NJZ002.
     Heat Advisory until 10 PM EDT Wednesday for NJZ004-006-103>108.
MARINE...None.

&&

$$

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