River Vale, New Jersey Weather Forecast Discussion

922
FXUS61 KOKX 061802
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
202 PM EDT Sat Sep 6 2025
.SYNOPSIS...
A cold front will impact the area today and pass offshore tonight.
High pressure builds in late Sunday and remains in control through
much of next week. A cold front approaches late next week, with
high pressure expected thereafter.
&&
.NEAR TERM /THROUGH TONIGHT/...
A cold front enters the forecast area this afternoon and moves east
through the area, pushing offshore late tonight.
Showers and thunderstorms becoming likely this afternoon into
evening across the area, weakening overnight as shower activity
continues mostly east of the city.
Shear and CAPE still look sufficient for the potential of severe
thunderstorms for NYC metro, NE NJ, and Lower Hudson valley into SW
CT. Main severe threat will be strong/damaging wind gusts, but
veering profiles with good speed shear could support organized cells
that maintain updrafts for large hail, and even an isolated tornado.
Other concern is flooding potential. PWATs increase to 1.75-2.00
inches right ahead of the cold front. The forward motion of storms
until around sundown will be a mitigating factor for flooding, but
the eastward motion of showers and remaining convection thereafter
should slow down. By this time, the collocation of the
convective potential (which will be diminishing) and the PWAT
axis will be east of the city, where FFG levels are harder to
reach. There seems to be a narrow window of time for flash
flooding opportunity in the more sensitive urbanized areas, and
will hold off of on what would be otherwise a very targeted
flash flood watch. But with that said, will need to keep and eye
on hi-res models to see if they continue to converge on
potential amounts and location of the qpf axis. Some HREF
members currently show localized 3-4 inch rain totals INVOF NYC
metro. HREF probs of 30% or greater for 3+ inches in 3 hours is
a pretty good indicator of flash flooding around here, but
values remain below 20% currently, and global models show lower
rain totals (which is usually the case) - under 2 inches
everywhere.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
The cold front will be not too far offshore on Sunday as it
continues to slowly shift east. Upper divergence from the right rear
quadrant of a strong upper jet streak maintains the threat of
showers primarily east of the city, and mostly during the morning
hours. Diminishing clouds otherwise elsewhere. High pressure builds
in Sunday night and remains in control through Monday night with dry
and less conditions. NBM looked good for temps.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
Key Points:
*Mainly dry with below normal temperatures next week.
Followed the NBM with this update.
Heights build next week with another large high pressure system
building into the area and holding on for much of the week.
Temperatures will be on the order of 5 to 10 degrees below normal
during the period.
In addition, building heights aloft through midweek will allow the
western Atlantic subtrop ridge to build closer to the east coast.
This will allow the forecast area to be close to the NW periphery of
some offshore frontal wave activity. The NBM has trended higher with
PoPs for midweek and may be too aggressive. Have kept for now given
its maxing out at low end chance (30-40%). This may end up trending
back down in future updates.
A late week cold front will bring another shot of cooler air for
next weekend with Canadian high pressure building in behind it.
Widespread low to mid 40s currently forecast for next Friday night
and Saturday night across the interior.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
A cold front gradually moves through the area this afternoon
through Sunday morning. High pressure builds in Sunday night.
VFR conditions across all terminals as of 18Z. However, a line
of showers and thunderstorms across Lower Hudson Valley and
northeast NJ is slowly pushing east and will affect the KEWR and
KTEB around 19Z (perhaps a bit sooner than currently is
forecast). This line will then continue to move east through
the afternoon and affect the other NYC terminals towards 19Z to
around 20Z. IFR to MVFR conditions are possible in any
showers/thunderstorms. The line is expected to weaken as it
pushes east, so as it reaches KGON, thunder is no longer
expected, with wind gusts associated with any thunderstorms
diminishing. After about 00Z lingering the threat for thunder
diminishes, but an isolated thunderstorm is still possible
through 01-02Z is expected through Saturday night with MVFR vsby
and cigs.
Southerly flow continues today at 10 kt to 15 kt, with gusts 20
to 30 kt. As the front approaches later in the day and early
evening look for a wind shift, especially in any thunderstorms
to the NW. Additionally, gusts of 30 to 40 kt (or higher if
storms become severe - generally across NE NJ and Lower Hudson
Valley) are possible with any thunderstorms and added gusts of
30 to 35 kt within the TEMPO groups for the +TSRA. Otherwise,
with the boundary settling nearby the winds likely go variable
in direction late in the TAF period for the city terminals this
evening.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
There remains some uncertainty with the timing of the arrival
of showers and thunderstorms this afternoon with amendments
becoming increasingly likely late in the day and into the
evening.
Gusts of 30 to 40 kt are possible with any of the stronger
thunderstorms today. If storms become severe gusts around 50 kt
are possible. Higher chances for severe are with KEWR and KTEB.
Start time of wind gusts may be off an hour or two.
.OUTLOOK FOR 00Z MONDAY THROUGH THURSDAY...
Sunday night: VFR.
Monday and Tuesday: VFR.
Wednesday: Potential for MVFR in -SHRA.
Thursday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
SCA remains posted for the ocean waters with seas up to 5 ft and
gusts up to around 25 kt. Occasional gusts to 25 kt possible this
afternoon/early evening elsewhere, but not enough for an advisory.
Lighter offshore winds for Sunday will promote sub-advisory
conditions on all waters. Sub-advisory conds then continue
through Monday night.
Easterly winds will strengthen on Tuesday due to a tightening
pressure gradient across the waters. E winds could gusts up to 20 kt
on the ocean waters with seas building to around 4 ft. There is a
chance that an E swell could help seas increase to around 5 ft on
Wednesday.
&&
.HYDROLOGY...
A fairly wide range of rainfall totals is expected for this
afternoon through tonight. Anticipating mostly 1-2 inches of rain
with locally higher amounts. Lower amounts are expected for eastern
LI and SE CT and perhaps the far NW zones. Areas of minor urban and
poor drainage flooding can be expected. There is a localized flash
flood risk as well, with overall best chances (15% chance) for the
urban corridor of NE NJ into NYC metro and northward into Fairfield
County. A 5% chance of flash flooding exists elsewhere. Timing for
the highest chances of flooding is from mid-afternoon to early
evening.
&&
.TIDES/COASTAL FLOODING...
There is a high rip current risk through this evening due to a
combination of a strong onshore flow (S 15-20kt) and southerly wind
waves of 4-5ft 7S. For Sunday, the risk at the very least will be
moderate, and possibly high with a southerly swell of around 3ft 7S.
However, winds will be less of a factor due to being offshore and
generally less than 10 kt.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents until 8 PM EDT this evening for NYZ075-
     080-081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ350-
     353-355.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...JP
MARINE...
HYDROLOGY...
TIDES/COASTAL FLOODING...

NWS OKX Office Area Forecast Discussion