000
FXUS61 KOKX 231738
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
138 PM EDT Sat Mar 23 2024
.SYNOPSIS...
A frontal boundary remains nearly stationary across Long Island
Sound this afternoon as associated low pressure tracks
northeastward across the region late this afternoon into this
evening. High pressure starts to build in from the north and
west tonight into Sunday and continues to ridge down from the
north Monday into Tuesday. A weakening warm front approaches
Tuesday night into early Wednesday. A frontal system then pushes
through slowly on Thursday with low pressure forming along the
boundary to the south and pushing offshore into Friday. Weak
high pressure attempts to build in afterwards.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
The warm front that was across Long Island Sound has become
nearly stationary, and is not expected to move much through this
afternoon, possibly moving northward across portions of
southeastern Connecticut. The associated low pressure system
centered over the Delmarva at 16Z will track northeastward into
early this evening. Precipitation continues across the region
with the heaviest expected from around 18Z south and west
through 03Z east. There may be a few pockets of freezing rain
across extreme western Orange County, and with the warmer air
not expected to reach into the interior isolated freezing rain
may remain into early afternoon.
Surface low pressure will strengthen slightly this afternoon as
it tracks across the region.
A surface trough will extend northeast towards our area ahead
of its passage. This feature, combined with an approaching upper
level trough, strong frontogenesis as the surface low nears,
and a nearby rear right quadrant of an upper level jet streak
will place our area under deep lift for a good part of the day.
With plenty of moisture available (pwats 1 to 1.25 inches which
is near the max moving average for this time of year) moderate
to heavy rain is expected. See hydrology section below.
The latest CAMs are in overall agreement of the axis of highest
rain totals being in a line from the NYC/NJ metro area up
through Fairfield and New Haven Counties. Light rain becomes
moderate this morning and then heavy by the afternoon.
Confidence in thunder is low, and latest CAMs and Bufkit
soundings are showing little to no surface and elevated CAPE, so
have removed the mention of thunder. If any does occur looks to
be over the waters and just south of the area. CAMs do still
show a convective line moving across the area and with a low
level jet of 60 to 70 kt higher winds may mix down with heavier
rain, and will leave the wind advisory as posted. Although
gusts will be marginal (mainly isolated 45 to 50 mph) soaked
grounds will make it easy for trees to be downed.
The system has sped up a bit and much of the area will likely
be dry by 03z tonight. Left timing of the Flood Watch alone for
now, but there is potential for it to end earlier.
High pressure noses down from the north behind the low pressure
system tonight as cool air filters back into the area. Strong
winds are expected the first half of the night. There is
potential for stronger winds to continue through the whole night
and for the Wind Advisory to be extended.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
The sun and dry conditions return on Sunday. In a cold
northerly flow highs will only reach the lower to mid 40s, which
is below normal for this time of year. Wind chill values will
be in the 30s. With high pressure nosing in from the north and a
low pressure system strengthening offshore, gusty conditions
will continue Sunday and Sunday night.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
High pressure continues to ridge in from the north on Monday
with dry weather expected across the entire area. Still breezy
mainly for coastal sections where the pressure gradient will be
a little tighter.
The low will meander offshore through early Tuesday with the
upper level ridge axis approaching late Mon and likely passing
through by Tue AM. At the same time in the low levels high
pressure ridges down from the north along the northeast coastal
plain. This should keep the low levels dry and with sinking
motion to the west of the offshore low and frontal boundary
expect a good deal of sunshine on Tuesday. Some high clouds
should start to push in for the afternoon and evening in advance
a warm front which draws closer Tuesday night. For now kept Tue
night dry as higher heights along the eastern seaboard should
slow down the advancement of lower clouds and precip from the
west. Heights lower for mid week and by Wednesday the flow aloft
becomes more cyclonic and thus introduced chance PoPs, with
some low end likely PoPs late in the day and at night. Questions
remain for Thursday with much of the global deterministic
guidance more to south and eventually to the east with a wave of
low pressure forming along a slow moving occluded / cold
frontal boundary for Thursday into Friday. Went a bit below
consensus / NBMEXP PoPs Thursday and Friday and kept chance to
low end chance PoPs in place for this timeframe with overall
confidence below average late in the period.
High temperatures near normal for Monday through Wednesday,
then a little warmer for Thursday and Friday.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --
Low pressure and a cold front pass through this afternoon into
early evening.
IFR and rain prevail through much of the daytime hours today. Rain
could be heavy at times, mainly after around 18z.
Winds varying mostly SE at around 15 kt with some gusts
20-25kt. Winds increase further in the late afternoon, becoming
mostly NW by the evening. Gusts 25-30kt this aftn. NW gusts
this evening 30-40kt.
LLWS for KNYC terminals and points east, with 40-50kts of flow at
2kft, except about 5-10kt stronger for KISP and KGON.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments likely for changing CIGs and VSBYs. An abrupt shift
from SE/E to NE/NW anticipated at some point between approx
19-23z.
OUTLOOK FOR 15Z SUNDAY THROUGH WEDNESDAY...
Sunday: VFR. N-NE wind gusts around 25 kt.
Monday: VFR. NE gusts 20-25 kt.
Tuesday and Wednesday: VFR.
Wednesday Night - Thursday: VFR. MVFR possible in showers.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
A Gale Warning remains for all waters for 35 kt wind gusts
later today and into Sunday morning. Seas on the ocean waters
build today and reach 10 to 12 ft tonight.
Low pressure will move through the area later today and bring
moderate to heavy rain this afternoon and evening. There is
potential for some thunderstorms and a finer line of convective
showers/thunderstorms. In any thunderstorm it is possible to see
40 to 45 mph gusts.
Once Gale conditions end on Sunday, Small Craft Advisories will
likely be needed for lingering elevated seas and 25 kt wind gusts as
high pressure builds in. Small craft conditions will remain in
place through Monday night for much of the coastal waters with
ocean seas remaining quite elevated. Perhaps more marginal small
craft conditions will remain for the western non-ocean waters.
Small craft seas will remain in place for the ocean waters
through Tuesday, with small craft gusts perhaps only remaining
for the far eastern waters into Tuesday afternoon.
&&
.HYDROLOGY...
Total rainfall amounts have increased slightly, but remain in the
2.5 to 3.5 inch range for most, with isolated amounts up to 4-5
possible. The latest guidance continues to show the highest axis
of rainfall on a line from the NYC/NJ metro area and up through
Fairfield and New Haven Counties in CT. The WPC also continues
the "slight risk" for our whole area. The bulk of the rain will
fall in a 6 to 8 hour period this afternoon into the early
evening. Widespread minor urban and poor drainage flooding is
expected, with scattered flash flooding possible. Minor flooding
is likely along several quick responding small rivers and
streams across NE NJ, the Lower Hudson Valley and Southern CT
this afternoon and tonight. Moderate flooding is also possible
along a few quick responding small rivers and streams,
particularly in NE NJ.
No hydrological impacts are anticipated in the long term Sunday
through Friday other than any possible lingering flooding along
rivers.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Flood Watch through Sunday morning for CTZ005>012.
Wind Advisory until 2 AM EDT Sunday for CTZ005>012.
NY...Flood Watch through Sunday morning for NYZ067>071.
Wind Advisory until 2 AM EDT Sunday for NYZ067>075-078>081-
176>179.
Flood Watch through late tonight for NYZ072>075-078>081-
176>179.
NJ...Flood Watch through Sunday morning for NJZ002-004-006-103>108.
Wind Advisory until 2 AM EDT Sunday for NJZ002-004-006-103>108.
MARINE...Gale Warning until noon EDT Sunday for ANZ331-332-335-338-340-
345-350-353-355.
&&
$$
SYNOPSIS...JC/JE/JT
NEAR TERM...MET/JT
SHORT TERM...JT
LONG TERM...JC/JE
AVIATION...BR
MARINE...JC/JE/MET/JT
HYDROLOGY...JC/JE/JT