920
FXUS61 KOKX 171611
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1211 PM EDT Sat May 17 2025
.SYNOPSIS...
-- Changed Discussion --
A cold front moves across the area late this evening. Low
pressure slowly moves across New England on Sunday sending a
secondary cold front across the area. The low slowly exits the
New England coast on Monday as high pressure gradually builds in
from the northwest. High pressure takes control Monday night
into early Tuesday night. A frontal system impacts the area
Wednesday into Friday.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Forecast on track this afternoon. A pre-frontal trough will
continue pushing east of the area. A lingering shower out east
is possible through 2pm.
Confidence with afternoon and evening convection remains low.
The weak shortwave associated with the aforementioned vorticity
will leave behind some subsidence as well as mid level dry air
this afternoon. Deeper mixing is also expected to develop, which
may also help mix out some of the higher dew points. Another
limiting factor will be the most organized forcing remaining
well to our north and west this afternoon and evening
immediately ahead of the parent upper low and surface low over
the Great Lakes. There is also a question of how much
instability will exist this afternoon despite limited cloud
cover, mainly due to the aforementioned dry air. Due to all of
these factors, have lowered PoPs into the evening and placed
the highest probabilities over the Lower Hudson Valley and
interior SW CT. Any convection looks isolated further south and
east closer to the coast/Long Island and may just be associated
with the cold front passage this evening.
The severe weather risk remains marginal as there is enough mid
level flow for shear supportive of updraft organization. The
main limiting factor again is with an organized trigger and the
amount of instability. While SPC has the area in a marginal
risk, think the probability for an isolated severe storm is
highest across the Lower Hudson Valley with the main threat from
damaging winds and potentially hail.
Convection may linger towards or just after sunset with the cold
front passage, but the severe threat diminishes quickly with
loss of heating. Any lingering showers should diminish through
the rest of the evening.
Highs in the middle to upper 70s to mid 80s are expected today.
Winds will likely gust 25 to 30 mph, especially across NE NJ,
NYC metro, and the Lower Hudson Valley where mixing is
maximized.
The cold front pushes through likely just before or around midnight
and will finally start to filter in a drier airmass in a westerly
flow.-- End Changed Discussion --
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
The upper level low will be centered to our north most of Sunday as
it very gradually shifts east. Some energy rotating around the low
will aid in pushing a secondary cold front through the area in the
evening hours. Some light rain showers are possible with this
feature, mainly across the interior. No thunder is forecast. Skies
also likely fill in around 4 kft, leading to mostly cloudy
conditions for the afternoon. In the cooler airmass, highs are
forecast to be in the upper 60s to lower 70s.
Surface troughing could continue into Monday as the low lingers off
the New England coast. Dry and sunny conditions are expected with
similar high temperatures as Sunday.
Both days could be gusty with some deeper mixing each day. 25 to 30
mph gusts are expected.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
Key Message:
* A frontal system likely impacts the region beginning Wednesday,
and continues into Thursday, and possibly into Friday.
No significant changes were made to the forecast for Tuesday into
the end of the week, as a frontal system remains likely to impact
the region late Tuesday night into Friday. An upper closed low
develop over the mid section into the upper Midwest by late Tuesday
night, and then the upper trough deepens and the closed low and
upper trough are slow to move eastward into the beginning of next
weekend. At the surface a deepening low moves out of the Mid
Mississippi Valley and into the Ohio Valley late Tuesday into
Wednesday. This low then moves slowly across the northeast Thursday
into Friday in association of the upper low becoming nearly
stacked. With a secondary surface low developing late Wednesday
into Wednesday night and increased precipitable waters values and
lift, there is the potential for a period of moderate rainfall.
Also, depending on the track of the low Thursday`s temperatures are
more uncertain. However, overall temperatures will be near or slightly
below normal levels Tuesday through Friday.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
A warm front moves through the area during the day. A cold front
moves across the region late this evening.
IFR/LIFR conditions persist for KHPN, KBDR, KGON this morning
but should improve fairly quickly over the next few hours.
Otherwise, VFR expected outside of any showers or TSRA. -SHRA
possible at the NYC terminals through early afternoon. Some TSRA
have developed outside of the NYC terminals and may impact KHPN
and KSWF through 16Z/17Z. If these persist, KBDR may end up
seeing TSRA by 16-17Z.
Another low chance of additional SHRA or TSRA this afternoon,
though the best chance remains for KSWF. Kept PROB30 to convey
the expected isolated nature of the TSRA, if any form at all.
South winds this morning increase to 10-15kt with some gusts
17-23kt late morning through the afternoon. With a cold front
passage late this evening winds shift to the W/NW, and may
become gusty late tonight. Gusts are more likely during the day
Sunday.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
A few light showers possible this morning, with no impacts to
conditions. Thunderstorm chances for late day into the evening
is low and continued the PROB30. There is a chance that thunder
does not occur.
.OUTLOOK FOR 15Z SUNDAY THROUGH WEDNESDAY...
Sunday: VFR. Slight chance of showers inland with MVFR
possible. W winds G20-30kt.
Monday - Tuesday: VFR. Monday NW winds G20-25kt day into evening.
Wednesday: MVFR or lower with showers likely, a slight chance of
thunderstorms in the afternoon. E wind gusts 15-20kt.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
-- Changed Discussion --
Conditions will remain below Small Craft Advisory levels for
the most part into this evening. However, some nearshore gusts
could reach 25 kt, mainly in the NY Harbor and western LI Sound.
Winds pick back up on Sunday and a Small Craft Advisory is in effect
during the daylight hours. Gusts could reach 25 to 30 kt, with seas
over the ocean reaching 4-5 ft. There is potential for the SCA to be
extended through Monday as marginal conditions are expected.
Winds and seas remain below advisory levels on all the forecast
waters Tuesday into Wednesday. With the approach of a frontal system
during Wednesday and easterly flow will be increasing and by late
day SCA conditions may develop on the ocean waters. With the
increased and persistent east flow into Thursday winds and seas on
the ocean waters will likely be at SCA levels. As low pressure
tracks northeast of the area Thursday night a northerly flow
develops and winds diminish, however, ocean seas are likely to
remain elevated into Thursday night.-- End Changed Discussion --
&&
.HYDROLOGY...
There are no hydrologic concerns through next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 6 AM to 6 PM EDT Sunday for ANZ331-
332-335-338-340-345-350-353-355.
&&
$$
SYNOPSIS...MET/JT
NEAR TERM...DS/JT
SHORT TERM...JT
LONG TERM...MET
AVIATION...MW
MARINE...MET/JT
HYDROLOGY...MET/JT