530
FXUS61 KOKX 110829
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
429 AM 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 TONIGHT/...
Cold front analyzed over far eastern Pennsylvania at 6Z continues
to slowly trek eastward. An associated broken line of showers
ahead of it continues to advance east through the region. A
locally heavy downpour or two is possible with this activity,
especially over Long Island and southern CT where a 50 kt LLJ at
925 mb is passing. Also can`t rule out an isolated rumble of
thunder here. Coverage is isolated to scattered though and not
all will see raindrops this morning. Otherwise, breezy and
muggy start to the day.

The remnant low of Beryl continues to lift northeast thru
Upstate NY, and the attendant cold front attempting to advance
east stalls over the region today. As it does, the axis of
deeper moisture shifts east and should keep much of any
additional wet weather focused just offshore, keeping the bulk
of the region dry this afternoon. 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 here 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 THROUGH SATURDAY NIGHT/...
The front that stalls over the area on Thursday retreats back
inland and over the local area on Friday as a wave of low
pressure over the Southeast begins to ride north along the
front. 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 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 WEDNESDAY/...
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 /08Z THURSDAY THROUGH MONDAY/...
A cold front will allow for showers and possibly some embedded
thunderstorms into early this morning mainly east of NYC terminals.
This cold front will continue to slowly move east later today and
work its way back west tonight. This will allow for showers to
return to the forecast late tonight.

Categories, mainly MVFR to IFR going into early this morning with a
return to VFR then expected thereafter through the rest of the TAF
period. KISP and KGON could hold on to lower clouds at MVFR or less
for a longer period of time, so these low conditions could very well
last the entire morning.

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 when there could also be some peak gusts to near 25 kt.

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

Timing of categorical changes in TAF could be off by 1-3 hours.

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


OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY...

Tonight through Saturday: MVFR or lower possible at times with
periods of showers/thunderstorms. Otherwise VFR.

Sunday: VFR.

Monday: Mainly VFR. A chance of afternoon into early evening showers
and thunderstorms with MVFR possible.

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

&&

.MARINE...
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.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents through 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
SHORT TERM...DR
LONG TERM...JM
AVIATION...JM
MARINE...JM/DR
HYDROLOGY...JM/DR
TIDES/COASTAL FLOODING...