000
FXUS61 KOKX 131406
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
906 AM EST Sat Jan 13 2024
.SYNOPSIS...
Deep low pressure tracks into Southeastern Canada today,
sending a frontal system through the region. An Arctic frontal
passage occurs on Sunday. Another passing offshore low may
produce some snow by the middle of next week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
Dense fog has been observed across the south shore of Island
and coastal Connecticut with area areas of dense fog to patchy
dense fog in interior Connecticut and northern Long Island.
Satellite shows clearing west to east just west of the city as
of 9am, so fog should clear over the next few hours.
A flood watch remains in effect for southern Connecticut.
Rain has ended or become scattered across Northeastern New
Jersey and the Lower Hudson Valley, while in Connecticut
moderate rainfall remains possible, with flooding also possible
through later this morning. The rain tapers off across
Connecticut later this morning.
A 981 mb surface low centered over Lake Huron at 11Z will be
tracking into Southeastern Canada later this morning and then
northward through the day. A warm moving into Central New Jersey
at 08Z will move northward through the region this morning,
followed rather quickly late this morning into this afternoon by
a cold front. The best isentropic forcing was moving through
Connecticut early this morning well ahead of the warm front, and
this is where moderate to potentially briefly heavy rainfall
remains possible. Elevated CAPE and instability have been weak
and removed the mention of thunder. While the system remains
fast moving precipitation will be quickly ending this morning
into early afternoon.
Temperatures continue to slowly rise ahead of and just behind a
warm front that was moving into the region at 11Z. High
temperatures will likely occur this morning, then temperatures
will start to fall this afternoon with the passage of a
cold front.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
Upper low pressure will remain, and meander, across Eastern
Canada tonight through Monday. A rather strong shortwave rotates
into the upper low late tonight and moves across the region
Sunday with an Arctic cold front passing through. A chance of
snow showers remains possible mainly Sunday afternoon. With
gusty winds and briefly heavier snowfall possible visibilities
may be quickly reduced as the snow showers move through the
region.
Lows will return closer to seasonable levels in the mid 20s and
lower 30s. Much colder air moves in behind the Arctic front
with temperatures as much as 10 degrees below seasonal normals.
Dry weather returns Sunday night and Monday.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
The models have been suggesting that the trof over the ern
portion of the country will allow low pres to develop over the
Atlc and potentially produce snow locally. The 12/12Z runs
supported this. It is too far out to hang your hat on any one
soln, but likely PoP for snow on Tue per the blended approach
was accepted and used in the fcst. Based on the 12/12Z
deterministic ECMWF/GFS, did keep things all snow over land, and
went with the colder NBM 50th percentile temp for Tue which were
close to the GFS MOS. There remains the possibility that if a
low does track close enough to the coast, mixing or a changeover
could occur in some areas.
The fcst tapers PoP off on Wed, but the overall timing of the
sys could slow and be Tue ngt into Wed. The GFS suggested this
possibility.
High pres and dry on Thu, then another low may take shape for
Fri. Earlier NBM PoP was about 30-40 percent, and went with
that.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
A warm front has moved through the NYC metro and Long Island
terminals and onto the CT coastline. A cold front will move
through early this afternoon.
IFR/LIFR cond along the coast attm should improve to VFR by
about 15Z-16Z at the NYC metros north/west, and 17Z-18Z across
Long Island.
Except for KGON where winds surged to 35G45kt with warm fropa, S
winds should lull for a while early this morning and then
increase while veering SW, and then become WSW-W with a cold
frontal passage from west-east from 17Z-19Z. Winds following
fropa should increase to 20-25G30-35kt with a peak gust to
35-40kt possible til 21Z.
WSW winds may hold into this evening, then slowly diminish
overnight.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
AMD likely for changing categories/wind shifts deviating from
forecast. Brief G35-40kt possible this afternoon.
OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY...
Sunday: Cold fropa around midday from the NYC metros north/west
and early afternoon east, possibly accompanied by brief snow
showers/IFR cond. W winds 15-25kt G30-35kt, isolated G40kt
possible with fropa.
Monday: VFR.
Tuesday: Chance of snow with IFR possible.
Wednesday: VFR. W-NW winds G25-30kt.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Gale warning continues on all waters through tonight, and was
extended on the ocean waters through Sunday. After a lull in the
winds on the non ocean waters Sunday morning, gales may return
Sunday afternoon. With a break of several hours did not want to
extend the gales there attm.
Winds decrease Sun ngt, with all areas likely blw SCA criteria
Mon and most of Tue. SCA may be needed, especially on the
ocean, Wed and possibly Thu with low pres over the Atlc.
&&
.HYDROLOGY...
Hydrologic impacts remain possible this morning, especially
across southern Connecticut where a flood watch remains until
15Z. Rainfall has underperformed across much of the area,
however a moderate rainfall is possible across southern
Connecticut with storm totals 1 to 1 1/2 inches are possible.
There are no hydrologic concerns tonight through Thursday at
this time. It is too early to talk specific snowfall amounts
with the potential low passing offshore early to mid next week.
&&
.TIDES/COASTAL FLOODING...
Widespread minor to moderate and areas of major coastal flood
potential continues for the Saturday morning high tide, as SE
gales build surge to 3-4 ft Fri night, with a wind shift to SW
gales Saturday morning near the time of high tide.
Winds last night were lower than fcst, so surge may be a little
lower than original expectations. Made only minor adjustments
from a blend of the previous forecast and the 06Z Stevens
NYHOPS 50th percentile.
SW to WSW flow later today will be conducive to water piling up
in the eastern Great South Bay, as winds push elevated water to
the east side of the bay with the wind shift. Potential for
widespread moderate to localized major exists on the south
shore bays. Elsewhere, widespread minor to locally moderate
flooding is expected.
Along the oceanfront, breaking surf height should be lower than
the last couple of events, but 12-16 ft breaking surf with
similarly elevated water levels, impacting compromised dune
structure will likely result in another round of widespread dune
erosion and scattered overwashes. Localized breaches possible
where dunes have been severely compromised and barrier beaches
are narrow.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...Flood Watch until 10 AM EST this morning for CTZ005>012.
Dense Fog Advisory until 11 AM EST this morning for CTZ006-
009>012.
Coastal Flood Warning until 3 PM EST this afternoon for CTZ009-
010.
Coastal Flood Warning until 2 PM EST this afternoon for CTZ011-
012.
NY...Dense Fog Advisory until 11 AM EST this morning for NYZ071-
079>081-178-179.
Coastal Flood Warning until 2 PM EST this afternoon for NYZ178.
Coastal Flood Advisory until 2 PM EST this afternoon for
NYZ072-074-075.
Coastal Flood Advisory until 3 PM EST this afternoon for
NYZ071-073-078-176-177.
Coastal Flood Warning until 6 PM EST this evening for
NYZ079>081-179.
NJ...Coastal Flood Advisory until 2 PM EST this afternoon for
NJZ006-104-106-108.
MARINE...Gale Warning until 6 AM EST Sunday for ANZ331-332-335-338-340-
345.
Dense Fog Advisory until noon EST today for ANZ331-335-340-345-
350-353-355.
Gale Warning until 6 PM EST Sunday for ANZ350-353-355.-- End Changed Discussion --
&&
$$
SYNOPSIS...MET
NEAR TERM...BR/MET
SHORT TERM...MET
LONG TERM...JMC
AVIATION...BG
MARINE...JMC/MET
HYDROLOGY...JMC/MET
TIDES/COASTAL FLOODING...