617
FXUS61 KOKX 302355
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
755 PM EDT Mon Sep 30 2024
.SYNOPSIS...
High pressure will be in place through Tuesday night. A weak cold
front from the west then moves through late Wednesday. High
pressure builds in Thursday and passes east on Friday. A cold
front is expected on Saturday, with high pressure building in
behind it to close out the weekend.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
No major changes were made to the forecast with this early
evening update. The only item worth noting is that dewpoints
were running a little dry in spots, so adjustments were made to
bring the forecasted dewpoints back in line.
High pressure will be weakly building in from the north tonight as
the center of the high remains over the Canadian Maritimes. No rain
is expected, but there is some uncertainty regarding how much lower
cloud cover ends up pushing in on an easterly low level flow. Will
leave out the mention of fog for now as radiation fog will probably
be mitigated by cirrus over the region. Can`t however rule out
patchy fog mainly over eastern sections where there will be more low
level moisture advection. Low temperatures around 60 in NYC and 50s
elsewhere.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
The pattern holds for Tuesday with high pressure stretching into the
forecast area from the NE. With dry mid-levels in place, not
expected any shower activity, Regarding clouds, best guess is that
it`s similar to what happened today - mostly cloudy to start, then
fewer clouds overall in the afternoon. Highs around 70. Continued
dry for Tuesday night with lows again around 60s in the city and 50s
for the rest of the area.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
High pressure noses in from the northeast to start the day on
Wednesday while a trough moves through the upper Great Lakes and
Ontario. This will bring a cold front across the northeast Wednesday
afternoon/evening. However, the front is expected to be weak, with
most of the temperature and dewpoint gradient focused north of our
area. I`ve kept slight chance POPs in the forecast for areas north
of NYC Wednesday, but they may not materialize this far south due to
weak forcing and lingering dry air. Cloud cover may still develop
ahead and along the front, clearing into Wednesday night after the
frontal passage.
High pressure looks to reestablish itself over the area on Thursday
and Friday after the cold frontal passage late Wednesday. Aloft,
heights rise ahead of an approaching broad upper level trough. With
S/SW flow through the column, we will see a warming trend through
Friday as well as increasing moisture. Highs both days will be in
the mid to upper 70s.
As the aforementioned upper level trough approaches, an associated
surface low likely forms and passes to our north. This would drag a
cold front through the area sometime on Saturday and result in some
showers. There are differences among the guidance with the strength
of the surface low/front, but given where the upper level trough
will likely be, the greatest lift would be to our north and we would
likely only see light showers here. The placement and strength of
the trough aloft, may also influence how cool we get following the
cold front.
High pressure builds in behind the cold frontal passage, with a
cooler and drier airmass likely moving in. Dewpoints drop to the 40s
and high temperatures will be in the upper 60s to low 70s.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
High pressure remains northeast of the region through the TAF
period.
VFR this evening transitions to MVFR overnight with development
of lower stratus. The MVFR stratus will last into early Tuesday
before scattering out. There is forecast to be some localized
IFR outside of NYC terminals overnight into early Tuesday
morning. Only have this at KGON in TEMPO but will be possible at
other non-NYC terminals as well.
Winds remain generally easterly through much of the TAF period
near 5-10 kts. A few gusts of 15-20 kt are possible Tuesday
afternoon, mainly along the coast.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Start and end time of MVFR could be a few hours off from TAF.
OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
Tuesday night: VFR initially, then MVFR with development of
stratus late.
Wednesday: MVFR possible with a slight chance of showers.
Thursday through Friday: Mainly VFR.
Saturday: Mainly VFR. A slight chance of showers with MVFR
possible.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Sub-advisory conditions are expected across all local waters through
tonight. While gusts will approach 25kt on the ocean starting
tomorrow, they should prevail below this. Seas however are expected
to build up to around 5 ft as an easterly wind averages a little
over 15kt. SCA has been issued for the ocean for tomorrow and
tomorrow night.
5 foot waves are likely to persist into Wednesday, gradually
dropping Wednesday night. Sub-SCA winds and waves are then
expected through Saturday.
&&
.HYDROLOGY...
There are no hydrologic concerns through this weekend.
&&
.TIDES/COASTAL FLOODING...
Astronomical tides will be increasing with the approach of a new
moon Wednesday afternoon. This combined with a persistent easterly
wind may push levels right up to minor flooding benchmarks for the
Wednesday morning high tide cycle. A statement may eventually be
needed to address this for the south shore back bays of Nassau and
Queens.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from noon Tuesday to 6 AM EDT Wednesday
for ANZ350.
Small Craft Advisory from 6 AM Tuesday to 6 AM EDT Wednesday
for ANZ353-355.
&&
$$
SYNOPSIS...JC/BR
NEAR TERM...JC/BR
SHORT TERM...JC
LONG TERM...BR
AVIATION...JM
MARINE...JC/BR
HYDROLOGY...JC/BR
TIDES/COASTAL FLOODING...