000
FXUS61 KOKX 071505
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1105 AM EDT Sat Oct 7 2023
.SYNOPSIS...
A cold front will move across the area this afternoon and into
this evening as the remnant low of Philippe moves northward,
well to the east of the area by Sunday morning. Low pressure
remains north of the area into the beginning of next week, with
frontal systems impacting the area around the middle and end of
the week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
For much of the morning, the showers/embedded thunderstorms
have remained disorganized and scattered. The heaviest rainfall
has remained south of the area off the NJ coast where radar has
estimated a max of 7 inches with hourly rates of 1-2"/hr. This
area has begun to shift ever so slightly east, with some heavier
showers to the north across Long Island and the Lower Hudson
Valley with pockets of 0.50 to 0.75"/hr rates.
With the incoming front and upper trough dynamics, this area
will have to be watched to see if it fills in moreso to the west
across NE NJ and NYC with training of cells south to north.
Latest MPD from WPC discusses high PW values around 1.5 inches
and weak moist adiabatic lapse rates through a deep warm cloud
depth of around 11,000 ft. Thus, the ingredients are in play
through early this afternoon for NYC and points west for
localized to scattered instances of flash flooding before the
cold front passes. To the east, it should be more isolated in
nature. However, latest CAMs are fairly progressive with the
convection along and ahead of the cold front, and out ahead it,
not very organized and progressive as well. Still though,
antecedent conditions for the area under the Flood Watch are
ripe and in some case only need 0.50-1"/hr for flash flooding
(NE NJ). So it won`t necessarily require much rain for some
locations,
The cold front then pushes the heavier rainfall eastward this
afternoon before exiting eastern LI/SE CT this evening. A
widespread 1-1.5 inches is possible for the western and northern
portions of the CWA. Eastern portions of the CWA may see a half
inch or less.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
The upper trough pushes the front through the area tonight and
closes off and becomes negatively tilted this evening as the
remnant low of Philippe merges with the frontal system.
Colder air moves in with temperatures returning to seasonal to
slightly below for tonight. Lows will be in the 40s for much of
the area.
Fairly dry conditions are then expected Sunday through Monday as
the area remains in the base of a large trough and the
associated cut-off low positioned well to the north. This will
allow for breezy NW winds continuing through the timeframe with
gusts upwards of 25-30 mph on Sunday and gradually diminishing
into Monday. Highs Sunday and Monday will be in the upper 50s to
low 60s.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A weak front comes thru late Tue into Wed with a few shwrs possible.
Little change in airmass expected with temps remaining a little blw
normal. Not much moisture to work with so any pcpn should be mainly
light.
Humidity increases Thu and Fri ahead of a strong cold front. Chances
for rainfall increase thru the period, although the heaviest pcpn
may hold off until Fri ngt or later. Temps warming back to around
normal with smaller diurnal swings.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
A cold front will pass through the terminals this afternoon and
evening. Low pressure will then meander over New England and
southeast Canada into early next week.
IFR with some areas of LIFR from showers. Showers will continue
into the afternoon, but likely focus over Long Island and
Southern Connecticut late afternoon and evening. A few isolated
thunderstorms have occurred, but confidence not high enough to
include in TAFs.
Improvement to MVFR is expected into the early afternoon for
NYC terminals on NW, but IFR may continue into the evening
further east. VFR returns late afternoon into the evening from
west to east.
E-ESE winds 5-10kt will shift to the NW behind the passage of a cold
front this afternoon. Gusts 20-25 kt should become frequent behind
the front and continue into the evening. Winds and gusts may
weaken a bit late tonight into early Sunday morning before
increasing after day break.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments likely due to changing flight categories.
Timing of improvement to VFR may be off by 1-3 hours.
Timing of cold front passage/NW wind shift may be off by 1-2
hours.
OUTLOOK FOR 15Z SUNDAY THROUGH WEDNESDAY...
Sunday: VFR. W winds 15-20G25kt.
Monday: Mainly VFR. Chance of showers at night. SW G15-20kt
Tuesday...Manly VFR. Chance of showers. S-SW G15-20kt.
Wednesday...VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
-- Changed Discussion --
A SCA remains on the ocean waters through at least Sunday night
as increasing swell from the remnant low of Philippe tracking
well east of the area. Behind a cold front tonight northwest
winds and gusts will be increasing, with gusts reaching SCA
levels across all the forecast waters by this evening.
West winds will produce SCA conditions on all waters Sun. Winds
will decrease Sun night, but seas on the ocean will remain at
or above 5 ft. Seas on the ocean are progged to be in the 3-5 ft
range Mon-Tue, then less on Wed. Seas then build again on Thu
ahead of a strong frontal sys. Otherwise, winds are progged to
remain blw SCA lvls Mon-Thu attm.-- End Changed Discussion --
&&
.HYDROLOGY...
-- Changed Discussion --
The potential for a narrow band of heavy rainfall remains this
morning into early this afternoon, though confidence in its
occurrence has decreased.
A basin wide average of 1 to 1.5 inches, with locally as much
as 2 to 3 inches, of rainfall is expected across much of
northeastern New Jersey into the Lower Hudson, New York City,
Nassau County New York, and Fairfield County Connecticut,
through this evening. A Flood Watch has been posted for these
areas with the potential for isolated to scattered flash
flooding. There is uncertainty as to where a band of heavier
rainfall sets up, with the possibility of being from
northeastern New Jersey into Nassau and Fairfield counties. In
locations outside of the Flood Watch 0.5 to around 1.0 inches of
rainfall will be possible tonight through this evening.
No hydrologic impacts expected Sun-Fri.-- End Changed Discussion --
&&
.TIDES/COASTAL FLOODING...
Long period SE swells from the remnant low of Phillipe will
build to 5 to 7 ft today and to 6 to 9 ft tonight, presenting
the likelihood of additional beach erosion/escarpment from an
east to west sweep of 5 to 7 ft breaking surf. Because water
levels are not astronomically high, the dune erosion threat
during times of high tide is isolated. Swells subside Sunday
into Sunday night.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...Flood Watch until 8 PM EDT this evening for CTZ005-009.
NY...Flood Watch until 8 PM EDT this evening for NYZ067>075-176>179.
NJ...Flood Watch until 8 PM EDT this evening for NJZ002-004-006-
103>108.
MARINE...Small Craft Advisory from 6 PM this evening to 8 PM EDT Sunday
for ANZ331-332-335-338-340-345.
Small Craft Advisory until 8 PM EDT Sunday for ANZ350-353-355.-- End Changed Discussion --
&&
$$
UPDATE..DW
AVIATION...BR