507
FXUS61 KOKX 151342
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
942 AM EDT Tue Apr 15 2025
.SYNOPSIS...
A cold front moves through the area this morning. A series of weak
surface troughs move through this afternoon through Wednesday. High
pressure starts to gradually build in Wednesday night, remaining in
control through Thursday night. A frontal system approaches
Friday and may impact the area from Friday night through
Saturday night. High pressure returns for Sunday. Another
frontal system may impact the area late Monday.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
The frontal boundary is moving a bit slower than previously
progged, but it does pivot through and gets clear of eastern
portions of the area by midday. Any sprinkles or light showers
associated with the boundary get east, with not much activity
expected for a few hours afterwards.
Thereafter however, a strong shortwave approaches. Towards later
in the afternoon CAMs suggesting widely scattered to isolated
shower activity. Cooling aloft will steepen lapse rates and
allow instability to increase. When these showers first move
into the area it looks like they will likely not be able to
produce any thunder because of a mid-level cap evident in model
fx soundings around 600mb. This cap is just below the -10C to
- 20C layer. Once this cap weakens by 20z or so, then about 100
to 200 J/kg of CAPE will be available in the -10C to -20C layer
and isolated thunder will be possible. With a dry sub-cloud
layer and strong mid-level flow, any stronger showers or
thunderstorms should be able to mix down 40+ kt gusts. Small
hail or graupel is also possible.
Outside of any showers or thunderstorms, the synoptic winds
themselves will be very gusty. Deep mixing is seen in model
soundings in strong CAA. The deepest mixing occurs in the western
half of the area before sunset and expecting the highest wind gusts
here. Mainly 35 to 40 mph with an occasional 45 mph gust possible.
Highs reach the 60s today, likely a bit earlier than climo for
western locations, maybe closer to 2 PM.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
Cyclonic flow aloft continues through Wednesday. At the surface a
series of weak troughs will move through. No precipitation is
expected from these features. Gusty winds expected again
Wednesday, but closer to 30 to 35 mph. Heights start rising
aloft Wednesday night with ridging aloft and high pressure
moving in at the surface. Light winds and clear skies expected
by Thursday night, so went straight CONSMOS guidance for now.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
A weakening ridge in the upper levels will push east of the area
Friday, while at the surface high pressure will be situated to the
south off the mid-Atlantic coast with a surface ridge axis extending
from it northward into southern Quebec. This will allow a
warm front to lift north Friday night and will be be the next
chance for precipitation. However, only light amounts of rain for
Friday night are expected at this time. The associated cold front is
expected to move through on Saturday night, with a secondary cold
front possibly moving through late Saturday night into early Sunday
morning. High pressure builds in behind the cold fronts for
the rest of Sunday.
With a building ridge moving into the region Thursday and a warm
front lifting north Friday night, a warming trend through the period
is expected. Temperatures in the 50s and 60s on Thursday will rise
into the 60s and 70s by Saturday for most areas. Cooler conditions
are expected along coastal areas. Cold air advection after the
passage of the cold front will temperatures back to near seasonable
levels for Sunday and Monday.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
A cold front moves across the terminals this afternoon. High
pressure then gradually builds in through Wednesday.
VFR through the TAF period. A brief shower is possible this
morning. Showers are then possible late this afternoon and early
evening. An isolated thunderstorm cannot be ruled out. Showers
look to end around 23z-01z.
Light winds to start will become SW and increase late morning
and early afternoon, becoming gusty 20-25 kt. Winds will shift
to the W and increase further to 15-25 kt with gusts 30-35 kt.
A few gusts to around 40 kt possible, especially with any
showers that develop late afternoon and evening. Winds should
then weaken a bit 01z-03z, but remain gusty around 25 kt
overnight into early Wednesday morning.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Start time of gusts may be off by 1-2 hours.
An isolated thunderstorm is possible 20z-01z. Isolated gusts
around 40 kt possible.
.OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY...
Wednesday: VFR. WNW winds G25-30kt.
Thursday: VFR. NW winds G15-20kt.
Friday: VFR. Chance of showers at night. S winds G15-20kt.
Saturday: Chance of MVFR in showers. SW winds G15-20kt.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
-- Changed Discussion --
Winds ramp up into the early afternoon. The Small Craft
Advisory now goes into effect everywhere at 12 noon. Tricky
wind forecast as there will be an inversion in place over the
waters through much of today. Meanwhile, gusts on land could
reach just below 40 kt around western Long Island, NYC,
northeast NJ and souther Westchester. Have decided to hold off
on a Gale Warning, but gusts right along the coast will at least
occasionally reach 35 to 40 kt. The inversion will weaken
through the day and stronger gusts will be able to mix down over
the open waters by tonight. There looks to be a few hour period
where gales are expected. Have also held off on Gale Warning
issuance for tonight given the brief period. A short fused Gale
Warning may be needed, or potentially an Marine Weather
Statement.
Gusts gradually lower on Wednesday. By Wednesday night most waters
will be below SCA criteria, with the eastern ocean zone likely
lingering due to 5ft waves. Sub-SCA conditions continue through
Thursday night.
Waves are expected to remain below SCA criteria through the
first half of Friday night but build to 4 to 6 ft late Friday to
around daybreak Saturday on the ocean. Waves continue to build to
4 to 8 ft by Saturday afternoon on a southerly flow ahead
of an approaching cold front. Waves slowly diminish thereafter
through Sunday, with all ocean zones below 5 ft by late Sunday
morning into Sunday afternoon.
Winds will remain below 25 kt through Friday, are expected to gust
25 to 30 kt kt by late Friday night into Saturday on the ocean
waters as a frontal system approaches from the west. Winds on the
ocean fall below 25 kt for Saturday night into Sunday. There is a
chance that non-ocean waters reach SCA gusts on Saturday.-- End Changed Discussion --
&&
.HYDROLOGY...
There are no hydrologic concerns through the start of next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT Wednesday for ANZ331-332-
335-338-340-345-350-353-355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JP/JT
NEAR TERM...JE/JT
SHORT TERM...JT
LONG TERM...JP
AVIATION...JP/DS
MARINE...JP/JT
HYDROLOGY...JP/JT