000
FXUS61 KOKX 091844
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
144 PM EST Sat Mar 9 2024
.SYNOPSIS...
Low pressure develops over the Carolinas today, then tracks across
the New York City Metropolitan Area tonight and into Maine on
Sunday. High pressure then builds in from the west through the
middle of next week, and offshore by the end of the week.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --
Forecast update to mostly reflect temperatures forecast.
Temperatures have been slow to rise this morning and high-res
forecast guidance has lowered temperatures though the day.
Generally looking at temperatures remaining in the lower and
middle 40s through the day, then rising into the upper 40s
tonight.
Otherwise, expect a cloudy day with rain developing from west to
east. The rainfall should be light for much of the day, before
the heavy rain in later tonight.
The models are in good agreement that a roughly 993 low will
track thru or very close to NYC at 6Z. The ECMWF is the only
model out of the main group a little outside of the cluster, and
this is only about 60 miles SE of the center of the low tracks.
As a result, the timing has been adjusted per the NBM which is
slightly faster than the previous fcst. Expanded slightly tstm
chances based on model track and timing. A track closer to the
ECMWF will relegate tstm chances to far ern zones.
After collaboration with surrounding WFOs, have decided to
expand the flood watch to include the remainder of the Lower
Hudson Valley and into western 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. The heaviest rainfall is expected this evening into the
early morning hours of Sunday. Across NYC and Long Island, we
are generally looking at a potential for minor/poor drainage
flooding tonight.
Winds will ramp up tngt as the low gets closer. Not much change in
the intensity fcst, with BL winds in the 30-40kt range expected to
yield gusts up to 40 mph, strongest at the coasts.
After the low passes, the rain shuts off quickly and a deep wly
component flow develops. There could be an hour or so of fog
with the low passage, but it has not been included in the fcst
due to the brevity. The NAM models the speed of the low at about
24kt.
The entire cwa should be mainly dry at 12Z based on the 00Z data.-- End Changed Discussion --
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
The massive h5 low will come thru about 00Z Mon. With the
substantial cold pool aloft, dpva, and even some sbcape, I still
think the NBM is way too low with pops. Blanketed the whole cwa with
aftn and eve 30 pops for sct shwrs of snow and rain. Some IP
also possible. Temps should fall in the aftn, with dewpoints
dropping into the 20s.
Sun will also mark the start of a period of strong W to NW
winds. Direction will be more W on Sun, then veer to the NW Sun
ngt as winds aloft also increase. The breezy conditions on Sun
will strengthen Sun ngt, with h85 around 50kt on Mon. Deep
mixing is likely in this pattern, so manually raised wind during
the day on Mon over the land. There is advy potential there.
The winds will likely keep wind chills from getting out of the
30s.
Although Mon will feel chilly, high temperatures are modeled to be
right around normal for the date. This will be the coldest day of
the fcst period with a warming trend starting on Tue.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
The gusty winds will diminish Mon ngt, then the rest of the
week will feature mainly quiet and dry conditions, with a
warming trend. A ridge builds over the eastern CONUS aloft as
high pressure remains in control at the surface. Highs Tuesday
will be in the 50s and by Friday they will be in the mid 50s to
upper 60s. A frontal system does approach late week and could
bring unsettled weather to the area. For now, stuck close to the
NBM during that time period as there is quite a bit of spread
among the deterministic guidance. This gives slight chance PoPs
Friday morning increasing to chance PoPs by the afternoon. This
would be an all plain rain event.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
Deepening low pressure will approach from the southwest today,
passing across the area late tonight, then to the north on
Sunday.
Widespread MVFR ceilings will lower this afternoon as rain
overspreads the area from west to east. IFR conditions are then
likely tonight with moderate to heavy rain. Improvement to MVFR
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.
E/SE winds 10-15 kt increase to 15-20 kt going into early
evening. Gusts will become more likely this afternoon up to 20
kt, but around 25 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.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments likely to refine timing of flight category changes
and the rain which could be a few hours off compared to TAF.
There could be fluctuation between MVFR and IFR this afternoon.
OUTLOOK FOR 18Z 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...
Seas on the ocean near sca lvls today, then winds and seas build
everywhere by this eve. Gale warning on the ocean, and srn and
ern waters for tngt. Elsewhere, a watch remains in effect with
more uncertainty.
Winds may stay just blw gale on Sun, even on the ocean, before
ramping up again Sun ngt and Mon. The watch has been extended thru
Mon for all waters.
Gusts lower Monday night, but could remain around Small Craft
Advisory criteria through Tuesday. Thereafter, winds and waves
look to remain below SCA criteria, with the next potential being
with a frontal system at the end of next week.
&&
.HYDROLOGY...
-- Changed Discussion --
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.-- End Changed Discussion --
&&
.TIDES/COASTAL FLOODING...
Coastal flood hazards have been updated with some adjustments.
The coastal flood watch for the south shore of Long Island for
tonight`s high tide cycle has been converted to a coastal flood
advisory. A coastal flood advisory has also been issued for
locations adjacent to lower NY Harbor and southern New Haven
county for tonight`s high tide cycle.
Elsewhere, a coastal flood watch remains in effect tonight for
the western half of Long Island Sound with advisories remaining
in effect for this morning`s high tide cycle across the south
shore back bays of western LI and western LI Sound, with a
statement for Lower NY Harbor.
A strengthening SE flow today with gale force gusts on the
adjacent waters tonight will coincide with high astronomical
tides, in some cases producing water levels 2 to 3 ft above
normal. This will result in widespread minor to moderate coastal
flooding during the times of high tide tonight. This morning`s
high cycle will be less impactful without strongest wind
forcing. The watch was kept up across western LI Sound tonight
due to a longer period of strong ESE winds. The forecast calls
for several locations to touch moderate with the potential of
going a few tenths higher. For the south shore of LI, the watch
was dropped as any moderate coastal flooding should be more
localized due to a shorter duration of the strongest winds.
As winds shift to the west Sunday morning, there is some uncertainty
with how much water escapes out of the south shore back bays of
western LI, and the potential for water sloshing to eastern
portions of the Great South Bay. Across Long Island Sound, this
seems less likely to be a problem due to a later high tide cycle
and thus longer duration of west winds.
For the ocean front, a forecast 8 to 12 ft surf will likely
cause scattered dune erosion.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...Flood Watch from 10 PM EST this evening through Sunday morning
for CTZ005-006-009-010.
Coastal Flood Watch from 9 PM this evening to 1 AM EST Sunday
for CTZ009.
Coastal Flood Advisory from 9 PM this evening to 1 AM EST
Sunday for CTZ010.
NY...Flood Watch from 10 PM EST this evening through Sunday morning
for NYZ067>071.
Coastal Flood Watch from 9 PM this evening to 1 AM EST Sunday
for NYZ071-073-078-176-177.
Coastal Flood Advisory from 6 PM to 10 PM EST this evening for
NYZ072-074-075-178-179.
Coastal Flood Advisory from 7 PM this evening to 1 AM EST
Sunday for NYZ079-081.
Coastal Flood Advisory from 6 PM this evening to midnight EST
tonight for NYZ080.
NJ...Flood Watch from 10 PM EST this evening through Sunday morning
for NJZ002-004-006-103>108.
Coastal Flood Advisory from 6 PM to 10 PM EST this evening for
NJZ006-106-108.
MARINE...Gale Watch from 6 PM EST this evening through Monday evening
for ANZ331-335-338.
Gale Warning from 6 PM this evening to 7 AM EST Sunday for
ANZ332-340-345-350-353-355.
Gale Watch from Sunday morning through Monday evening for
ANZ332-340-345-350-353-355.
Small Craft Advisory until 6 PM EST this evening for ANZ350-
353-355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JMC
NEAR TERM...BC/JMC
SHORT TERM...JMC
LONG TERM...JMC/JT
AVIATION...MW
MARINE...JMC/JT
HYDROLOGY...JMC
TIDES/COASTAL FLOODING...