000
FXUS61 KOKX 030246
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1046 PM EDT Tue Apr 2 2024
.SYNOPSIS...
A warm front will continue to slowly approach from the south
tonight. Low pressure strengthening to the southwest early
Wednesday will then pass over or just south of the area
Wednesday evening through Thursday morning. The low will drift
slowly east of New England later this week into Saturday, with
high pressure building in early next week.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
-- Changed Discussion --
Forecast remains generally on track with some adjustments to
temperatures, dew points, and the PoPs to account for the latest
trends in observations and radar coverage of showers to the
west.
A warm front will continue to slowly approach from the south
tonight as strong surface low pressure and an upper low slowly
spin in place near the western Great Lakes. Latest radar trend
and hi-res guidance indicate light rain lessening in coverage
from west to east this evening before picking up again after
midnight.
E flow will continue and strengthen overnight. Gusts along the
coast should likely reach 30 to 35 mph. Temperatures won`t drop
too much overnight with the strong easterly flow, rain and
cloud cover. Expect lows in the upper 30s/lower 40s.-- End Changed Discussion --
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
Upper level low and associated surface low continue to spin in
place over the Great Lakes Wednesday through Wednesday night.
Low pressure then forms along a frontal boundary near the Mid-
Atlantic extending southeast of the low over the Great Lakes.
This low looks to strengthen and pass over or just south of our
area deepening to around 985mb. This low will bring another
round of moderate to locally heavy rain as well as high winds.
Model fcst winds have increased over the past few runs and have
bumped forecast winds up. Both the 12z NAM and GFS show 65 to
75 kt at 925mb. Bufkit soundings show no real inversion in place
with mean boundary layer winds around 50 kt at several coastal
locations. Have issued a High Wind Watch for all of Long Island,
NYC, coastal CT and southern Westchester and Hudson Counties.
In these areas, expecting a period from mainly Wednesday
afternoon through the first half of Wednesday night where wind
gusts could potentially reach 60 mph. Elsewhere (except Orange
County and Western Passaic County) have issued a Wind Advisory
for 45 to 50 mph wind gusts.
As previously mentioned, this low will also bring another round
of moderate to locally heavy rain to the area, as well as the
potential for isolated thunderstorms. See hydrology section
below. Any thunderstorms are expected to remain below severe
criteria as instability is real marginal. MUCAPE values will
likely only be up to a few hundred J/kg. The Storm Prediction
Center has maintained the "general thunderstorm" area in their
outlook.
This low will also bring coastal flooding to the area. See
the tides/coastal flood section below.
As the low pull away, cold air gets wrapped up into the system
and precip may end as a wintry mix across far northern and
western locations. At this time, there is potential for snow and
sleet to mix in. There will likely be little to no accumulation
due to marginal surface temperatures.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
A blocky pattern will persist through the period courtesy of a
developing omega block over the CONUS and southern/central
Canada. Its eastern leg (the upper low associated with this
week`s storm) will be moving across Thu night, accompanied by
snow/rain showers especially in the evening. Another fairly good
chance for showers will come on Friday as a mid level vort max
trailing the upper low moves across. This disturbance will have
some low level instability to work with as model fcst sounding
show steep sfc-H7 lapse rates and available moisture above the
LCL, so have bumped up NBM PoP to at least 30 percent
throughout, and while fcst does not include this could not
entirely rule out some isolated thunder and/or graupel/small
hail with some of this activity.
Another vort max pinwheeling around the slow moving upper low E
of New England should bring another chance for showers on Sat
mainly across S CT and ern Long Island. Then fair and milder wx
likely for Sun-Tue with sfc high pressure finally building in
and heights rising aloft. Siding more with slower ECMWF vs
faster GFS solution with a weakening upper ridge axis sliding
across, and some mid level shortwave energy riding atop the
ridge axis in the afternoon. This means there could be a fair
amt of bkn high clouds present during the time of the solar
eclipse in the afternoon.
Temps a few degrees below normal Thu night through Sat should
moderate to near normal on Sunday, then warm up to a few
degrees above normal Mon-Tue, with highs in the lower/mid 60s
both days.
&&
.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
A large developing low pressure system will impact the area
through Thursday. The center of the low passes over the area
Wednesday night into Thursday morning.
Mainly IFR expected for all terminals through the TAF period,
though some spots tonight may fluctuate to MVFR. LIFR
conditions will be possible, especially for coastal terminals
into the early morning Wednesday. A break in the rainfall is
likely through 6-8Z for much of the area. More steady and
moderate rainfall moves into the area by morning and throughout
the day on Wednesday. Heavy rain with embedded TS possible
after 21Z Wednesday, but confidence in occurrence and coverage
too low to include in the TAFs at this time.
E winds will increase tonight, strengthening significantly on
Wednesday. Gusts may be more occasional tonight before
increasing in frequency near or just before the Wednesday
morning push. Winds gust beyond 35 kt at the NYC terminals
between 12-15Z. Peak gusts to around 50 kt possible after 18Z
Wednesday across the NYC and coastal terminals, particularly at
KJFK, KLGA, KHPN, KBDR, KISP. Winds less further inland but
gusts up to 40kt remain possible. Winds slowly weaken and become
more northerly with the passage of the low pressure after 04Z
Thursday.
Though winds at 1-2kft will be 50-60 kt Wednesday afternoon
into the evening, LLWS was not included in the TAF as surface
winds will be strong as well.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments likely through the TAF period for changing cigs/vis
and possible fluctuations in flight categories.
Gusts may fluctuate between occasional and frequent tonight
before becoming prevailing by 09Z-12Z Wednesday.
OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY...
Wednesday Night: IFR or lower in rain. The rain could be mixed
with wet snow at KSWF late Wednesday night. E winds with peak
gusts around 50 kt possible. Winds 50kt or more at 2kft.
Thursday: MVFR or lower with lingering rain, possibly mixed with
wet snow at KSWF. NW gusts 20-25 kt.
Friday: Mainly VFR. Slight chance of showers. NW flow with gusts
around 25kt.
Saturday: MVFR possible with N flow.
Sunday: VFR with N flow.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Winds will be increasing tonight and a Gale Warning is in effect
for the ocean W of Moriches Inlet, where gusts up to 35 kt are
expected after midnight, with ocean seas building to 7-9 ft.
A Storm Warning is then in effect starting Wednesday morning on
all waters. Strong low pressure will pass over or just south
of the waters and bring a period of 50 kt wind gusts, mainly
from Wednesday afternoon through he first half of Wednesday
night. Waves on the ocean waters likely reach 15 to 17 ft on the
ocean waters and 9 to 11 ft across the Sound.
Winds drop below Gale criteria by Thursday morning, with
lingering SCA criteria mainly in the form of elevated ocean
seas persisting into Thu night-Fri night. Some gusts up to 25 kt
are also possible in NW flow Fri afternoon and early evening
on most waters, and later into Fri night on the ocean.
&&
.HYDROLOGY...
An additional 1.5 to 2.5 inches of rainfall is expected tonight
through early Thursday. The bulk of this rain will fall
Wednesday afternoon and evening. Rainfall rates with the round
on Wednesday will be mainly 0.25 to 0.5 inch per hour, with
locally 0.75 to 1.0 inches per hour in any thunderstorms. Poor
drainage flooding and urban low lying flooding is possible
along with minor river flooding across quick responding rivers.
The WPC has maintained a marginal risk of excessive rainfall.
&&
.TIDES/COASTAL FLOODING...
Local minor flooding benchmarks may be reached, or just touched,
late tonight/early Wednesday morning along the Long Island south
shore back bays.
Around 2.5-3 ft of surge is needed for minor coastal flood Wed
aft/eve and around 3.5-4 ft for moderate coastal flooding.
With easterly winds ramping up through gale to storm force
during the time of high tide, as well as building wave action,
widespread moderate coastal flood thresholds are likely to be
eclipsed along the southern and eastern bays of Long Island and
along the western Sound. Elsewhere widespread minor coastal
flooding likely. In addition, the combination of heavy rain and
elevated water levels on Wednesday afternoon into evening may
cause localized flash flooding along some shoreline roads and
properties.
Easterly winds gradually subside late Wed night as low pressure
moves over the area, and then switch to NW gales behind the low
Thu AM. High easterly swells will likely inhibit drainage,
particularly bay areas, bringing potential for widespread
moderate flooding (locally major for the southern and eastern
bays of Long Island) late Wednesday night into early Thu
morning. The coverage and areas of greatest coastal flood
impact will be highly dependent on track of the low, and timing
of the wind shift from easterly SCA/Gales to northwest gales.
Forecast is based on a 75th percentile of Stevens, blended
with ETSS, STOFS guidance, which applies a bit of margin for
safety. This will be refined over the next 24 hours.
Along the oceanfront, breaking waves of 6-10 ft Wednesday into
Thursday morning, along with elevated water levels, will
result in widespread beach flooding and erosion. Scattered areas
of dune erosion with localized overwashes are likely during the
times of high tide Wed afternoon into Thursday morning.
Along Long Island Sound, breaking waves of 3-7 ft Wednesday
evening, along with elevated water levels, will result in
beach erosion with damage to shoreline structures possible. Wave
splashover over bulkheads and seawalls will likely exacerbate
flooding of shoreline roadways and properties. A similar threat
exists for the twin forks, with breaking waves of 4-8 ft
Wednesday evening and Thursday morning.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Wind Advisory from 11 AM Wednesday to 5 AM EDT Thursday for
CTZ005>008.
High Wind Watch from Wednesday morning through late Wednesday
night for CTZ009>012.
Coastal Flood Warning from 4 PM Wednesday to 10 AM EDT
Thursday for CTZ009-010.
Coastal Flood Watch from late Wednesday night through Thursday
morning for CTZ011-012.
NY...Wind Advisory from 11 AM Wednesday to 5 AM EDT Thursday for
NYZ068>070.
High Wind Watch from Wednesday morning through late Wednesday
night for NYZ071>075-078>081-176>179.
Coastal Flood Warning from 4 PM Wednesday to 10 AM EDT
Thursday for NYZ071-073-078-176-177.
Coastal Flood Advisory from 2 PM Wednesday to 7 AM EDT
Thursday for NYZ072-074-075.
Coastal Flood Warning from 2 PM Wednesday to noon EDT Thursday
for NYZ079>081-179.
Coastal Flood Advisory from 2 PM to 7 PM EDT Wednesday for
NYZ178.
Coastal Flood Warning from 3 AM to 7 AM EDT Thursday for
NYZ178.
NJ...Wind Advisory from 11 AM Wednesday to 5 AM EDT Thursday for
NJZ004-103>108.
High Wind Watch from Wednesday morning through late Wednesday
night for NJZ006.
Coastal Flood Advisory from 2 PM Wednesday to 7 AM EDT
Thursday for NJZ006-104-106-108.
MARINE...Small Craft Advisory until 6 AM EDT Wednesday for ANZ331-332-
335-338-340-345-350.
Storm Warning from 6 AM Wednesday to 2 AM EDT Thursday for
ANZ331-332-335-338-340-345-350-353-355.
Gale Warning until 6 AM EDT Wednesday for ANZ353-355.
&&
$$
SYNOPSIS...BG/JT
NEAR TERM...BG/JT/MW
SHORT TERM...JT
LONG TERM...BG
AVIATION...MW
MARINE...BG/JT
HYDROLOGY...BG/JT
TIDES/COASTAL FLOODING...