955
FXUS61 KOKX 111811
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
211 PM EDT Thu Jul 11 2024

.SYNOPSIS...
A cold front stalls over the region today. An area of low
pressure along the front tracks nearby Friday and Saturday, and
remains within the area Sunday into early Monday. Then, these
features move farther north of the area Monday into Tuesday with
another cold front approaching for the middle of next week.

&&

.NEAR TERM /THROUGH FRIDAY/...
Cold front was moving slowly through western Connecticut and
western Long Island, and will becoming stationary late this
morning into this afternoon, as the remnant low of Beryl
continues to lift northeast thru Upstate NY.

With the subtly drier air mass, dew pts fall back into the 60s
for the western half of the region. This should keep heat
indices a bit lower than recent days, and under advisory
criteria despite temperatures approaching 90 in NE NJ and the
NYC metro once again.

Rain chances begin to rise tonight as the boundary begins to
wiggle back west, with CAMs hinting at scattered showers pushing
back onshore from west to east overnight into Friday AM.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
The front that stalls over the area on Thursday retreats back
west Friday as a wave of low pressure over the Southeast begins
to ride north along it. The main shortwave energy is progged to
pass over the region into the start of the weekend and this will
instigate more widespread showers and perhaps a few embedded
thunderstorms as it does so. Scattered showers much of Friday
increase in coverage late, becoming likely everywhere overnight
into Saturday as the associated slug of moisture arrives. PWATs
climb once again over 2 inches and heavy downpours will be
possible with this activity. Given the high moisture content,
these could lead to nuisance and minor urban and poor drainage
flooding, and present at least a low threat of flash flooding.
WPC has maintained a marginal risk of excessive rainfall in this
period, which lines up with a potential for isolated instances
of flash flooding. Total QPF thru Saturday is generally around
an inch or so, but expect locally higher amounts in any areas of
training or thunderstorms.

The shortwave lifts north by Saturday night and drier air
filters in from the west. Temperatures both Friday and Saturday,
while held down some by rain and clouds, should still achieve
the 80s regionwide, with overnight lows in the 70s. Stayed close
to guidance consensus with this update.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Main points:

* Potentially another heat wave Sunday into next week with hot and
  humid conditions forecast for many locations. Max heat indices
  forecast get near the 90 to 100 degree range for much of the area.
  Excessive heat will be possible for some interior and urban
  locations as heat indices forecast at times to reach above 100 and
  could trend a few degrees higher with subsequent forecasts.

* Chances for showers and thunderstorms, mainly late afternoon into
  early evening and to the north and west of NYC Monday and Tuesday.
  A more widespread chance of showers and thunderstorms exists for
  Wednesday into Wednesday night. Extent both spatially and
  temporally appears to be greater for thunderstorms towards the
  middle of next week due to more vertical forcing.

* Precipitable waters potentially in the 1.5 to 1.9 range for early
  to mid next week, making heavy rain a possibility with any
  thunderstorms that form.

Overall pattern from LREF depicts flattening of mid level ridge and
zonal flow establishing itself across the region Sunday into early
next week. LREF depicts a strengthening mid level trough approaching
for midweek. This gets relatively closest to the region Wednesday
night next week.

At the surface, low pressure and a frontal boundary remain near the
region Sunday into early Monday. These features then move farther
north of the region while a cold front eventually approaches from
the west. The cold front will be approaching towards the middle of
next week.

The features of low pressure and nearby frontal boundary however
appear quite weak with dry conditions expected Sunday into Sunday
night. Chances for showers and thunderstorms return to the forecast,
mainly north and west of NYC and mainly for the late afternoon into
early evening on Monday as well as Tuesday. The forcing from daytime
trough development along with the buildup of low level instability.

The chances for showers and thunderstorms grow Wednesday as a cold
front approaches and increased forcing aloft allows for greater
lifting as a result.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
A cold front will stall within the region and eventually move
back west tonight into early Friday.

VFR conditions are expected through much of tonight. Conditions
deteriorate early Friday morning to potentially MVFR in
showers.

Winds generally S-SW during the TAF period with wind speeds of
near 10-15 kt. Gusts up to near 20 kt are forecast, mainly
during the afternoon with peak gusts at times to near 25 kt.
Gusts subside tonight with winds generally SW near 5-10 kt.

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

Timing of categorical changes in TAF could be off by 1-3 hours
tonight into Friday morning.

Uncertainty on end time of wind gusts, which also could be off by 1-
3 hours.

OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY...

Friday through Saturday: MVFR or lower possible at times with
periods of showers/thunderstorms. Higher chances of
thunderstorms Friday night and Saturday. Otherwise VFR.

Sunday: VFR.

Monday and Tuesday: Mainly VFR. A chance of afternoon into
early evening showers and thunderstorms with MVFR possible,
mainly north and west of NYC terminals.

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

&&

.MARINE...
Updated probabilities of showers across the eastern waters
this morning. Otherwise, no changes to the winds and seas.

Small Craft Advisory on the local ocean waters remains in
effect through tonight with elevated seas between 5 and 8 ft
and SW flow gusts up to 25 kt. Winds subside this evening, but
seas likely hang near 5 ft thru Friday and the advisory may need
an extension.

Thereafter, the pressure gradient will be weak enough to allow
for both winds and seas to stay below SCA thresholds across all
the forecast waters.

&&

.HYDROLOGY...
Showers and thunderstorms Friday and Saturday associated with a
nearby boundary and low pressure wave could produce locally
heavy downpours that lead to nuisance flooding in urban and poor
drainage areas. Isolated instances of flash flooding are possible
as well. WPC has outlined the region in a marginal risk of
excessive rainfall.

With higher precipitable waters moving into place for early to mid
next week, heavy rain will be a possibility with any thunderstorms
that develop. The precipitable waters reach between 1.5 and 1.9
inches, below the max records but at times nearing the 90th
percentile. Too early to ascertain any specific rainfall amounts,
but localized heavier rainfall can be expected.

&&

.TIDES/COASTAL FLOODING...
There is a high risk of rip current development along all ocean
beaches today and Friday with surf heights up to 5 ft and a
southwest wind between 10 and 15 kt.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents until 9 PM EDT this evening for NYZ075-
     080-081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EDT Friday for ANZ350-353-355.

&&

$$

SYNOPSIS...JM/DR
NEAR TERM...DR/MET
SHORT TERM...DR
LONG TERM...JM
AVIATION...20
MARINE...JM/DR/MET
HYDROLOGY...JM/DR
TIDES/COASTAL FLOODING...