475
FXUS61 KOKX 121857
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
257 PM EDT Sat Oct 12 2024
.SYNOPSIS...
A cold front was moving south of Long Island this morning, and
will stall to the south tonight, then lift north as a warm
front late Sunday into Sunday night along with developing low
pressure. The low will drag a cold front through on Monday, with
high pressure slowly building in thereafter.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A cold front moved through the region this morning, and at 14Z
was moving south of Long Island. Initial gusts with the frontal
passage peaked at 28 to 32kt. Mixing to around 900mb continues
through the day, and continued, and increased gusts into late
afternoon, ending 22Z/23Z, as winds aloft diminish and mixing
slowly weakens with peak heating having passed.
Dry conditions continue today with a cold front south of the
region. Meanwhile, a weak upper shortwave moves off the northern
New England coast by midday. The flow aloft looks to become
more zonal and progressive over southern New England and the
Northeast as a whole by this afternoon. With a gusty NW flow,
downsloping off the higher terrain will allow temperatures to
warm to above normal levels today, with highs in the upper 60s
to mid 70s.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
High pressure builds in for the first part of tonight. The cold
front begins to move north late tonight, with a weak area of low
pressure over the mid-West riding the frontal boundary and heading
east. At the same time, an upper level trough dives south from the
western Great Lakes region and aid in some intensification of this
low over the Northeast. Most of the deterministic models show the
low intensifying as it rounds the trough and heads into northern New
England. A period of light rain showers is therefore in the forecast
from Sunday into Sunday night. Some lingering showers are possible
for eastern areas Monday morning. Some CAMs try to bring in some
showers late tonight into NYC and points east, however looking at
forecast soundings, instability does not look impressive to warrant
any POPs. Any showers should be limited to the interior for tonight,
with the best chances for any precipitation actually occurring
Sunday night.
There is also a brief period window for the possibility of thunder
for the first half of Sunday night as instability aloft increases to
a couple hundred J/kg, so continue to carry a slight chance for
thunder from 2 am to 8 am Sunday night into Monday morning.
Generally, light rain is expected with anywhere from 0.10"-0.50"
in the forecast. The highest amounts are expected across the
Lower Hudson Valley and inland CT, while lower amounts are
expected across NYC, NE NJ, and Long Island (eastern areas of
Long Island may be on the higher side of the aforementioned
range as the low intensifies east of the area, it could bring
some heavier showers in before it departs).
There is a decent temperature gradient across the forecast area on
Sunday, with area north and west of NYC seeing highs in the 50s,
while the city and coastal areas see highs in the upper 60s to lower
70s. This is because the frontal boundary is expected to be within
the forecast area on Sunday. However, there is a large spread in
temperatures seen in the NBM for Sunday (as much as 9 degrees in
some cases) as there is uncertainty in where the frontal boundary
will be. If it ends up farther north than is currently forecast,
then temperatures will likely be warmer than what is currently in
the forecast. If it remains to the south, then cooler temperatures
can be expected.
The cold front moves through on Monday and high pressure builds in
behind it. Precipitation will end from west to east through the day,
with dry conditions expected everywhere by sunset. Highs on Monday
will be seasonable, ranging from the upper 50s inland, to the upper
60s along the coast. With the strengthening low pressure to the
north and the high building in, a strong pressure gradient will set
up over the area, and breezy conditions are expected, with gusts of
20 to 30 mph.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Dry conditions expected, with the area remaining in between low
pressure over ern Canada and high pressure over the Plains states as
a closed low to our northeast is slow to move out of New England and
ern Canada. A NW flow will bring down cooler air, with low temps Tue
and Wed from the mid 30s to mid 40s, and highs only in the 50s. Kept
the fcst dry Tue night but cannot totally rule out a few wraparound
snow or rain showers making it to wrnmost Orange County.
Slow moderation in temps (more daytime than nighttime) should occur
late in the week as the air mass modifies. Some frost is possible at
night especially Wed night and Thu night, as winds decouple both
nights and as dewpoints start to rise Thu night.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
High pressure builds in from the NW this afternoon into
tonight. A warm front lifts into the region Sunday afternoon,
ahead of an approaching frontal system Sun eve.
NW winds 15G20-25kt, diminishing late in the afternoon into the
early evening. Light winds veering to NE overnight, and then
becoming E/NE Sunday AM. Warm front lifts through most terminals
from SW to NE late Sun AM into mid Sun aft. Windshift to S/SW with
gusts 20-25 likely in it wake. A few showers possible at KSWf
Sunday, and then all terminals late aft/eve.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Gusts to 25 kt through 20z, diminishing through the eve push.
Winds generally right of 310 magnetic.
S/SW gusts 25 to 30 kt possible for Sun aft/early eve push. -SHRA
possible for late aft/eve push.
OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY...
Sunday aft: VFR with chance of late aft/eve showers, greatest at
KSWF. S/SE 10-15G20-25kt for most terminals. SW winds 20g30kt
possible for KEWR/KTEB in the afternoon/early eve.
Sunday night: Slight chance of an evening tstm. Showers possible
overnight, particularly northern terminals. S/SW winds becoming NW
10-15G20kt overnight.
Monday: Showers possible in the AM. MVFR conds possible for KSWF and
eastern terminals in the AM. Otherwise VFR. W/NW winds 15-20G25-
30kt, becoming NW 10-15G20kt by late Mon eve.
Tuesday and Wednesday: VFR. W/NW winds 10-15G20-25kt.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
-- Changed Discussion --
With wind gusts and seas below advisory levels east of Fire
Island Inlet have cancelled the advisory that was in effect.
Conditions remain below SCA criteria on all waters through
Sunday morning. The approach of a frontal system to the south
and then a strengthening pressure gradient from Sunday afternoon
into Monday will mean a prolonged period of SCA on the ocean
waters during this time frame as ocean seas build to 4-8 ft and
gusts of 25-30 kt are possible. By Monday afternoon, all waters
should see gusts 25-30 kt. Did not issue SCA for this period
just yet.
SCA cond in NW flow should continue on all waters Mon night,
with gusts 25-30 kt and ocean seas 5-8 ft. Thereafter, SCA
cond still likely on the ocean Tue into Wed night, with seas
3-5 ft and gust up to 25 kt. Could also see a brief round of SCA
cond on the non ocean waters especially the Sound late day Tue
into Tue night, with gusts up to 25 kt.-- End Changed Discussion --
&&
.HYDROLOGY...
There are no hydrologic concerns through the forecast period.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...None.
NJ...None.
MARINE...None.-- End Changed Discussion --
&&
$$
SYNOPSIS...BG/JP
NEAR TERM...JP/MET
SHORT TERM...JP
LONG TERM...BG
AVIATION...NV
MARINE...BG/JP/MET
HYDROLOGY...BG/JP