000
FXUS61 KOKX 092112
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
412 PM EST Sat Mar 9 2024
.SYNOPSIS...
Low pressure tracks across the New York City Metropolitan Area
tonight and into Maine on Sunday. High pressure south of the area
will be in control Tuesday. A frontal system may stall nearby for
mid week, before lifting north as a warm front late Thursday and
Friday. Another frontal system follows on Saturday.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
A stormy night is still on track across the area, as low pressure
moves over the region tonight.
Forecast models continue to be in very good agreement that a roughly
993 low will track over or very close to NYC around 06Z. Have stuck
fairly close to the NBM POPs tonight. The best chances for rain are
this evening through at least the first half of the overnight. After
06z, POPs start to taper off from SW to NE, with most of the rain
ending towards daybreak.
Rainfall amounts will range between 1 and 2 inches with some of the
rain falling heavy at times. After collaboration with surrounding
WFOs, have decided to expand the flood watch to include the
remainder of the Lower Hudson Valley and southern CT. There will be
a chance of flash flooding along some of the rivers and streams
across the watch area due to antecedent wet soils and the
anticipated rain totals. Across NYC and Long Island, we are
generally looking at a potential for minor/poor drainage flooding
tonight.
Winds will increase a bit tonight as the low gets closer. Expect
gusts between 35-40 mph closer to the coasts. Winds will be less
across the interior.
Lows tonight will be in the upper 30s and 40s.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
-- Changed Discussion --
Not too much change in the short term period.
Sunday will be the start of a period of strong W to NW winds.
Direction will be more W on Sun, then veer to the NW Sunday night as
winds aloft also increase. The breezy conditions on Sun will
strengthen Sunday night, with 850mb winds around 50kt on Monday.
Deep mixing is likely in this pattern. Wind advisory headlines seem
likely on Monday, but its still a tad early right now for headlines.
The winds will likely keep wind chills from getting out of the 30s.
A large upper level low passes over the region late Sunday and
Sunday night. As it does, expect some additional cloud cover.
Also, with the substantial cold pool aloft, dpva, and even some
sbcape, will continue to keep a 30 POP in the forecast. Expect a
chance a snow and rain showers. Can not rule out some ice
pellets as well. Temps fall late in the afternoon, with
dewpoints dropping into the 20s.
Temperatures on Sunday will be in the middle and upper 40s to 50s.
While Monday will feel chilly, high temperatures are expected to be
in the 40s.-- End Changed Discussion --
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Key Points...
* Winds diminish Monday night into Tuesday morning...
* A warming trend takes place...
The upper level low gets further to the northeast and well up into
the Canadian Maritimes Monday night and into Tuesday morning. This
will lead to a diminishing of the winds. Afterwards for midweek, in
response to the digging and amplification of the upstream trough
over the Rockies a ridge builds across the East. This will lead to a
warming trend with temperatures averaging well above normal for the
mid and late week period with dry conditions.
The trough will approach late in the week and likely bring another
round of unsettled weather in the form of rain late Friday and
Saturday with the arrival of low pressure and its associated
occluded / cold front. There are differences in timing and in the
handling of the Pacific branch and any potential interaction with
the pure southern branch of the jet. Thus chose to take a consensus
blend, which the NBM seemed reasonable with respect to PoPs for
Friday and Saturday.
The greatest deal of uncertainty deals with temperatures for
Wednesday through Friday. By Thursday max temperatures are likely to
get into the 60s across a good portion of the area, particularly
away from the coast. If more of a westerly component to the wind
develops closer to the surface, then temperatures could get even
warmer than currently advertised. Some 70s therefore are a
possibility away from the coast later in the week.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
Deepening low pressure will approach from the southwest this
evening, passing across the area late tonight, then to the north on
Sunday.
Widespread MVFR ceilings will continue to lower into this evening as
rain overspreads the area from west to east. IFR conditions are then
likely tonight with moderate to heavy rain. Thunder can`t be ruled
out, mainly for the NYC terminals, but not confident enough to
include in the TAFs. Improvement to MVFR expected from 09Z to 12Z as
the rain exits to the east. MVFR conditions may persist into the
early afternoon on Sunday before cigs rise to VFR for most. Eastern
terminals may struggle to rise to VFR. There may be some residual
scattered rain or snow showers Sunday afternoon into the evening
which may result in brief MVFR conditions.
E/SE winds 10-15 kt increase to 15-20 kt going into early evening.
Gusts will become more likely around 25-30 kt going into early
evening. LLWS arrives towards late evening with SE winds near 45-50
kt for most coastal terminals. Winds veer around to the W/SW toward
12Z Sunday. Gusts of 20-25kt persist through much of the day
tomorrow, perhaps increasing up to 30-35 kt by Sunday evening.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments likely to refine timing of flight category changes and
the heaviest rain which could be a few hours off compared to TAF.
Isolated thunder remains possible into the overnight but not
confident enough to include in the TAFs.
OUTLOOK FOR 21Z SUNDAY THROUGH THURSDAY...
Sunday: MVFR or low end VFR by afternoon. Winds W 20-25G30-35 kt by
afternoon. Rain showers possible with MVFR conditions.
Sunday night: MVFR possible with any rain or snow showers.
Otherwise, VFR. W winds 15-20G25-30kt.
Monday: VFR. NW winds 20-25 kt with gusts near 35-40 kt.
Monday night: VFR. NW winds near 20 kt in the evening with gusts up
to 25-30 kt, eventually decreasing to 10-15 kt with gusts 20-25kt
late.
Tuesday: VFR. NW winds 10-15G20kt.
Tuesday night through Thursday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Low pressure passing over the area waters tonight will result in
gales on all waters except the NY Harbor and the far eastern portion
of LI sound. A Small craft advisory is in effect for those areas.
Sunday, the gales go away and will need to be replaced with Small
Craft headlines. There may be a period on the non-ocean waters where
conditions fall below SCA. However, Wind and seas increase again
Sunday night into Monday. Gale watches remain in effect for all
waters on Monday. Ocean seas will will remain 8-10 ft tonight
through Monday.
Gales will give way to small craft conditions Monday night as the
winds begin to diminish. Any small craft conditions early on Tuesday
should give way to sub small craft conditions for late Tuesday. More
tranquil conditions are expected towards Wednesday and much of
Thursday with light winds and ocean seas closer to 2 ft.
&&
.HYDROLOGY...
Around 1 to 2 inches of rain is expected to fall this afternoon
through tonight. The higher amounts are expected to be north and
west of NYC. There will be the chance of flash flooding, primarily
along the smaller rivers and streams due to antecedent wet
soils and the anticipated rain totals. The heaviest rainfall is
expected this evening into the early morning hours of Sunday.
Otherwise, mainly minor/poor drainage flooding will be possible
tonight.
There are no hydrologic concerns Sunday night through next week.
&&
.TIDES/COASTAL FLOODING...
Strengthening SE flow with gale force wind gusts on the coastal
waters tonight will coincide with high astronomical tides, in some
cases producing departures of 2-3 ft above astronomical tides. This
will result in widespread minor and moderate coastal flooding during
the times of high tide tonight and Sunday morning.
For tonight: Per bias-corrected Stevens 50th percentile guidance
have issued a coastal flood warning for S Nassau and SW Suffolk for
tonight, and upgraded the watch to a warning for S
Fairfield/Westchester/Bronx/N Queens/N Nassau, all of which should
see a long enough period of strong SE winds to push water levels
above moderate thresholds. Strong onshore flow and associated wave
action will likely exacerbate problems along the coast of S
Fairfield as seas in the western Sound just offshore reach 3-4 ft
around the time of high tide.
Replaced the coastal flood watch with an advisory for NW Suffolk,
where guidance predicts water levels to approach moderate thresholds
in some spots , but where offshore flow may have some mitigating
influence.
Coastal flood advisories are in effect for all other waters. A river
flood advisory (FLS) will also be issued for the Hudson for Rockland
and N Westchester where minor coastal flood impacts are also
expected this evening.
For Sunday morning: Still have concern that strong SE flow followed
by strong SW-W flow will result in water remaining trapped in the
Long Island south shore bays, which would then slosh eastward into
the Great South Bay, and that water levels elsewhere will be higher
than than the Stevens 50th percentile. Took a 2:1 blend of the
Stevens 95th and 50th percentile forecasts, and nudged that toward
PETSS 50th percentile guidance on the Long Island south shore bays
where higher.
This forecast results in moderate flooding for Jamaica Bay (S Queens
portion) and another round for S Nassau, so a coastal flood warning
was issued for both areas for Sunday morning. Water levels farther
east into the Great South Bay should at least reach minor thresholds
due to water sloshing eastward. Minor flooding also expected on all
other remaining coastlines including the lower Hudson.
For the oceanfront, a forecast 8-11 ft surf (highest east across
Suffolk County) will likely cause scattered dune erosion Sunday
morning.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Flood Watch from 10 PM EST this evening through Sunday morning
for CTZ005>012.
Coastal Flood Warning from 9 PM this evening to 1 AM EST
Sunday for CTZ009.
Coastal Flood Advisory from 7 AM to 2 PM EST Sunday for
CTZ009>012.
Coastal Flood Advisory from 9 PM this evening to 1 AM EST
Sunday for CTZ010>012.
NY...Flood Watch from 10 PM EST this evening through Sunday morning
for NYZ067>071.
Coastal Flood Warning from 9 PM this evening to 1 AM EST
Sunday for NYZ071-073-176-177.
Coastal Flood Advisory from 7 AM to 2 PM EST Sunday for NYZ071-
073-176-177.
Coastal Flood Advisory until 10 PM EST this evening for NYZ072-
074-075-178.
Coastal Flood Advisory from 7 AM to 11 AM EST Sunday for
NYZ072-074-075.
Coastal Flood Advisory from 9 PM this evening to 3 AM EST
Sunday for NYZ078-079.
Coastal Flood Advisory from 9 AM to 1 PM EST Sunday for NYZ078-
079.
Coastal Flood Warning until 1 AM EST Sunday for NYZ080.
Coastal Flood Advisory from 7 AM to 1 PM EST Sunday for NYZ080-
081.
Coastal Flood Advisory until 3 AM EST Sunday for NYZ081.
Coastal Flood Warning from 7 AM to 11 AM EST Sunday for NYZ178-
179.
Coastal Flood Warning until 11 PM EST this evening for NYZ179.
NJ...Flood Watch from 10 PM EST this evening through Sunday morning
for NJZ002-004-006-103>108.
Coastal Flood Advisory until 10 PM EST this evening for NJZ006-
104-106-108.
Coastal Flood Advisory from 7 AM to 11 AM EST Sunday for
NJZ006-104-106-108.
MARINE...Small Craft Advisory until 7 AM EST Monday for ANZ331-335-338.
Gale Watch from Monday morning through Monday evening for
ANZ331-332-335-338-340-345.
Gale Warning until 7 AM EST Sunday for ANZ332-340-345-350-353-
355.
Small Craft Advisory until 6 PM EST this evening for ANZ350-
353-355.
Gale Watch from Sunday evening through Monday evening for
ANZ350-353-355.
&&
$$
SYNOPSIS...BC
NEAR TERM...BC
SHORT TERM...BC
LONG TERM...JE
AVIATION...MW
MARINE...BC/JE
HYDROLOGY...BC
TIDES/COASTAL FLOODING...