432
FXUS61 KOKX 092038
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
438 PM EDT Wed Apr 9 2025

.SYNOPSIS...
-- Changed Discussion --
High pressure along the coast through Thursday will slowly give
way to weakening low pressure over the Ohio Valley and a warm
front to the south. Low pressure over the Mid Atlantic states on
Friday will then slowly lift north and east through Saturday,
passing to the east on Sunday. High pressure will briefly build
across on Monday before a frontal system moves through from late
Monday night into Tuesday. High pressure will again build in
from the southwest for the middle of next week.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
-- Changed Discussion --
Sfc high pressure will remain just off the coast tonight. A
S-SW flow mainly along the coast and in the metro area
expected, with winds becoming light/vrb inland. In the zonal
flow aloft mid level clouds should make it into the area from W
PA and OH especially from NYC north/west. Temps should be
warmer than those of last night in most places, mainly mid 30s
to around 40, except inland and across the Long Island Pine
Barrens where radiational cooling will allow temps to fall to
the mid 20s to lower 30s once again.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
-- Changed Discussion --
An upper trough crossing the Great Lakes should slowly amplify
during this time. WAA between this system and the offshore high
should allow for further increase in clouds, perhaps some
afternoon sprinkles from NYC north/west with the best chances
well inland. Temps while warmer than recent days will still be
below normal, with highs mostly in the lower 50s, and upper 40s
along the immediate south shores of Long Island and SE CT.

GFS quicker than the NAM to bring rain in Thu afternoon/night
and wetter overall. Have split the difference between the two
but even this looked too aggressive with the high to the east
slow to budge, so tempered with slightly lower NBM PoP. This
give chance PoP for all areas during Thu evening, then likely
from NYC west late Thu night. Sfc temps should cool off to
35-40 but with warming temps aloft expect p-type to be all rain.
-- End Changed Discussion --

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
Global models are all in good agreement with closing off an
upper low over the Mid Atlantic states on Friday, then lifting
it slowly north and east through the weekend. However, there are
some differences with the positioning of the surface low, with
the 12Z GFS tucked closer to the upper low, tracking it closer
to the coast. The GEFS mean and most of its members are farther
east, supporting the operational consenus. This difference is
also reflected in the positioning of the warm conveyor belt
rains coming in off the Atlantic. The GFS is farther to the
west, in line upper jet dynamics and upper difluence, focusing
some heavy rainfall across NE NJ, NYC, the Lower Hudson Valley
and SW CT Friday night. The operational runs of the ECMWF and
Canadian are father west with this axis and also focus the
heaviest overrunning rains farther to the east across eastern LI
and SE CT, even moreso over SE New England. Bottom line, there
is some uncertainty with the axes of heaviest rain late Friday
into Saturday. A consensus forecast, using the NBM, gives much
of the area 1.00 to 1.50 inches through Saturday. However, did
cut down the higher amounts (2 inches) of the NBM across western
areas due to the uncertainty and location of the western axis.
WPC has the entire forecast area in a Marginal Risk of Excessive
Rainfall. Current thinking is flooding will mainly be of the
minor nuisance variety. Any thunderstorms look to be isolated
and across eastern LI and SE CT where there is marginal
instability. Rain diminishes in intensity Saturday afternoon and
night to light rain and/or drizzle, which may continue into
Sunday, especially for the eastern half of the forecast area. In
addition, a gusty easterly flow up to 25 mph is expected across
coastal locations Friday into Saturday.

A weak high pressure ridge will then move across the area
Monday, followed by a frontal system impacting the area late
Monday night into Tuesday with a low chance of showers. Low
pressure departs to the north across eastern Canada on
Wednesday, with high pressure building in from the southwest.

For temperatures, daytime highs will be in the upper 40s to
lower 50s Friday and Saturday, which is on the cool side. Lows
though will be closer to normal due to the cloud cover, in the
upper 30s inland and the lower to mid 40s along the coast. Expect
a warmup into Tuesday ahead of the cold front with highs
getting into the 60s and possibly around 70 for the NJ/NYC metro
north into the Lower Hudson Valley. This is about 5 to 10 degrees
above normal.
-- End Changed Discussion --

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
-- Changed Discussion --
High pressure builds over the Atlc thru Thu.

VFR thru the TAF period.

WNW winds backing to the W and diminishing thru this eve. An onshore
component bringing winds closer to 210 true on the south coasts at
times thru 02Z. Winds become lgt and vrb tngt, then become SE and
strengthen thru the day on Thu.

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

As winds lighten, some variability in direction likely thru 00Z.

.OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY...

Rest of Thursday: MVFR possible by late Thu ngt with -RA possible.
SE winds about 10-15kt.

Friday: MVFR with periods of IFR. Rain. E flow 10-20kt.

Saturday: MVFR or lower. Chance of light rain. NE winds 15-20 kt
possible.

Sunday: MVFR possible with winds becoming NW.

Monday: VFR.

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

&&

.MARINE...
-- Changed Discussion --
Some gusts in SW flow on the central Sound were approaching but
remaining just shy of 25 kt attm. Sub SCA cond expected on all
waters through Thu night, with winds becoming S-SW tonight (with
some gusts close to 20 kt on the western ocean waters) this
evening, backing SE Thu afternoon/evening, then E (with some
gusts to 20 kt on the ocean) late Thu night as high pressure
over the waters slowly retreats.

A strengthening easterly flow will bring SCA conditions to the
ocean waters Friday into Saturday with gusts up to 30 kt and
seas building to 6 to 9 ft on the ocean on Saturday. Conditions
look more marginal for the non-ocean waters. SCA seas will
likely linger Saturday night into Sunday on the ocean with a
gradually weakening NE flow.
-- End Changed Discussion --

&&

.HYDROLOGY...
-- Changed Discussion --
Rainfall from Friday evening through Saturday afternoon will
average from 1 to 1 1/2 inches. These amounts should limit any
flooding to the minor nuisance variety. However, there is a fair
amount of uncertainty with the location of the higher rainfall
axes during this event. These details should be better resolved
as we draw closer to the event.
-- End Changed Discussion --

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$

SYNOPSIS...BG/DW
NEAR TERM...BG
SHORT TERM...BG
LONG TERM...DW
AVIATION...JMC
MARINE...BG/DW
HYDROLOGY...BG/DW