okx-afd on 2025-04-30

382
FXUS61 KOKX 301522
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1122 AM EDT Wed Apr 30 2025

.SYNOPSIS...
High pressure will be in control through Thursday. A warm front
approaches Thursday night and lifts through the region on
Friday. A cold front then passes through the region Saturday
into Saturday night, with a wave of low pressure developing
along it as does so. High pressure then attempts to build in
from the north and west into early next week, while an upper low
meanders nearby.

.NEAR TERM /THROUGH TONIGHT/...
Forecast on track this morning. The cold front has moved east of
the region any any light rain showers have ended.

High pressure will build in from the NW for the rest of the day
and through tonight. Still somewhat breezy through at least
early afternoon before winds become lighter later today. A dry
NW flow will promote above-normal temperatures with some
compressional heating via downsloping, and for south-facing
coasts, winds should be strong enough to prevent sea breezes
pushing in during the day. Leaned more toward the NBM 50th
percentile, which is warmer than the deterministic NBM given the
temperatures at the top of the mixed layer. See the fire
weather section below for potential impacts of the dry and
breezy conditions.

The surface ridge axis moves into the forecast area tonight with
winds continuing to weaken. Strong radiational cooling conditions
should therefore develop in the usual spots as winds become calm and
cirrus probably holds off through the night. NBM as usual looks too
warm for these areas, so instead blended MET and MAV MOS. This
results in lows in the mid-upper 30s well NW of city and in parts of
the LI Pine Barrens Region, however no frost concerns at this time.

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Surface ridge axis will be over or just to our east through the day
on Thursday with still some slight ridging aloft. This will keep us
dry through the daytime hours. High temperatures near normal.

Surface low pressure shifts NE through the Great Lakes Region during
Thursday night. A leading warm front is progged to reach our
doorstep by daybreak Friday. Increased moisture with 850mb theta-e
advection and isentropic lift bring chances (40-50%) of light
rain/drizzle/showers during the night.

The warm front lifts north through the area on Friday with mainly
afternoon and nighttime showers and thunderstorms possible as a cold
front approaches. While strong thunderstorms will be possible for
roughly the western half of the forecast area based on progged CAPE
and shear profiles in the afternoon and evening, severe storms are
not anticipated at this time. No flooding impacts are expected
either. NBM looked good for high temps, but adjusted downward in
some spots with a southerly flow expected off the waters.

.LONG TERM /SATURDAY THROUGH TUESDAY/...
An unsettled start (at least) to the long term as a cold front works
east through the region Saturday. Guidance still indicates frontal
wave development along the nearby boundary, likely enhancing
rainfall and leading to periods of showers much of the day. Can`t
rule out a few thunderstorms as well, though instability appears
relatively low and severe weather is not expected.

Thereafter, wildly diverging solutions amongst global guidance
continues to lead to considerable uncertainty and low confidence
into next week. One camp, which includes the GFS/GEFS, has a less
amplified, more progressive trough that advances far enough east
before closing off into an upper low near the Canadian Maritimes.
This allows high pressure to build in locally and dries the region
out. Meanwhile, EPS and GEPS members largely have a sharper, slower
trough that closes off to our west, meandering within the Eastern
CONUS for several days and leading to a much more dreary and wet
outlook. The 00Z ECM, for example, advertises a washout, producing 4
to 5 inches of rainfall across portions of the local Tri State thru
Monday, with more beyond that as the system lingers thru mid next
week. The same run of the GFS yields barely a half inch, all with
the frontal wave on Saturday. With this large spread, used the
national blend for PoPs, yielding chance (25-40%) Sunday and beyond.
The associated energy is just moving onshore western Canada, and
additional sampling over the next day or so should help resolve the
solution.

Given the potential for these persistent unsettled conditions,
temperatures will be highly dependent on the synoptic outcome and
have stayed close to consensus with this update.

.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
A cold front tracking through the region pushes offshore late
this morning. High pressure builds in thereafter from the north
and west.

VFR thru the TAF period.

Winds will be NE near 15 kt with gusts around 20 to 25 kt
expected through this afternoon. Gusts diminish early this
evening across the region, with decreasing flow veering
northerly toward daybreak Thursday, then SE by Thursday
afternoon.

...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

Timing of gust onset/cessation may be off by an hour or two.

.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...

Thursday: VFR.

Thursday night: Chance of showers after midnight with MVFR cond
possible.

Friday: Chance showers/tstms with MVFR or lower cond from mid
afternoon into the night. S winds G20kt at the NYC metros and along
the coast.

Saturday: Showers likely and possibly a tstm with MVFR or lower cond
expected.

Sunday: Chance of showers with MVFR cond likely.

Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90

.MARINE...
-- Changed Discussion --SCA remains on the two eastern ocean zones at this point, and
this will be due mainly to residual elevated wave heights. Sub-
advisory conditions by late afternoon, continuing through Friday
morning. With southerly winds increasing Friday afternoon,
expecting a return to SCA conditions at least on the ocean and
possibly on some of the other waters as well.

Ocean seas may linger near 5 ft thru late Saturday before lowering.
Sub SCA conditions then expected on all waters early next week.-- End Changed Discussion --

.FIRE WEATHER...
NW winds pick up and will likely gust to around 25 mph at times
through early afternoon. Winds then likely to diminish thereafter.
Minimum RH levels are expected to be 20 to 30 percent, resulting in
an elevated risk of fire spread. Special Weather Statements have
been collaborated with state agencies and remain posted for all of
our NY, NJ, and CT zones today.

.HYDROLOGY...
There are no hydrologic concerns through the forecast period.

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 2 PM EDT this afternoon for ANZ350-
353.-- End Changed Discussion --

SYNOPSIS...JC/DR
NEAR TERM...BC/JC
SHORT TERM...JC
LONG TERM...DR
AVIATION...JM/DR
MARINE...BC/JC/DR
FIRE WEATHER...
HYDROLOGY...JC/DR