399
FXUS61 KOKX 181423
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1023 AM EDT Sun May 18 2025
.SYNOPSIS...
Low pressure is slow to exit the New England Coast and will
send several surface troughs through the area through Monday.
High pressure noses in from the north thereafter through Tuesday
night. A frontal system impacts the area Wednesday into Friday
night, moving northeast of the region Saturday.
&&
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Forecast remains generally on track with mostly clear skies
slowly becoming more cloud covered from northwest flow advecting
a low-level cloud deck into the area. Temperatures are rising
slightly quicker than forecast so adjusted high temperatures
today slightly upwards, mainly for Long Island and the NYC
metro, but an upper trough should limit the amount of surface
heating allowing temperatures to rise more than the middle 70s.
The upper level low can be seen well on latest water vapor
imagery centered to our north and moving over northern NY. At
the surface, a cold front is now pushing offshore and W/NW flow
is filtering in some drier air. The upper level low and
associated surface low are slow to exit the area and will
gradually move off the New England Coast tonight. The surface
low will send a few surface troughs through the area through
Monday, the first being this afternoon.
Today starts off mostly sunny, but with the help of cyclonic
flow aloft a decent cloud deck around 4 kft should fill in and
lead to mostly cloudy skies. There is also potential for some
light showers, mainly across the Lower Hudson Valley and
interior southern CT. If anything makes it farther south it will
likely only be sprinkles. The more notable weather today will
be the gusty W/NW flow. There is some concern with how well
mixed we can get once clouds fill in, but confidence was high
enough to go above the NBM90th percentile for gusts as even
shallow mixing up to 950mb could bring down some 35+ mph gusts.
Stuck with NBM for highs today, giving upper 60s to mid 70s.
Mixed in other global guidance and NBM10th percentile for Td as
the NBM has shown some high bias in drier regimes.
The pressure gradient increases a bit over the area tonight and
sustained winds may increase slightly, but gusts lower with
less mixing. Stuck with NBM for lows with the lack of strong
radiational cooling. Lows will be in the 50s.-- End Changed Discussion --
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
A quick approaching shortwave will move overhead on Monday
along with another surface trough. Not expecting any
precipitation from these features. Gusty winds do continue
though, a few mph lower than today.
Winds finally start lowering Monday night with high pressure
nosing in from the north. Thinking winds will still be a bit too
high though for ideal radiational cooling conditions.
Light winds expected on Tuesday with at least a mostly sunny
sky through the early afternoon. Some mid and upper level clouds
may move in from the northeast in the afternoon thanks to the
influence of the still-departing upper level low.
Late in the period, Tuesday night, unsettled weather returns
with an approaching large frontal system. Slight chance PoPs
begin after midnight for the western third of the area.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Key Message:
* A frontal system impacts the region Wednesday into Friday night.
Periods of moderate rainfall are possible Wednesday afternoon
into Wednesday night.
The forecast remains fairly consistent from previous forecasts
with the approach of a frontal system Tuesday night that impacts
the region during Wednesday into at least Friday, and possibly
into Friday night. An upper level trough deepens across the
upper midwest and into the Great Lakes region Wednesday into
Wednesday night with a closed low developing. The upper low will
be slow to depart to the northeast as pieces of energy rotate
through the low. The upper trough begins to weaken and move
northeast during Saturday. Meanwhile, at the surface low
pressure moves out of the Great Lakes and into the region
Wednesday into Wednesday night. The guidance is still developing
a deepening low along the mid Atlantic coast late Wednesday.
This low deepens through Thursday while tracking over or just
east of the region. This is in response to the upper low energy
moving toward the coast Wednesday. With an influx of Atlantic
moisture and strong lift with the upper low and surface low.
periods of moderate to possibly briefly heavy rainfall are
becoming more likely late Wednesday into Wednesday night.
However, no hydrologic impacts are expected at this time. With
the upper low slow to depart have kept chances and slight
chances of precipitation in the area into Saturday. With
extensive cloud cover and rainfall, daytime temperatures will be
5 to near 10 degrees below normal Wednesday through Friday, and
night time lows will be near to around 5 degrees below normal.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
Low pressure over Northern New England into the Canadian
Maritimes moves little through tonight.
VFR. The only exception is a low chance of MVFR cigs with
showers at KSWF this afternoon.
W-NW 15-20 kt, with gusts 25-35 kt, with the highest gusts late
afternoon into the evening, and mainly along the coast. A few
gusts may peak at 40 kt along the coast. Winds become more NW
tonight with winds around 15 kt and gusts 20-25 kt. Gusts may
briefly end at a few terminals outside of the NYC metro area
late tonight.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
A few gusts late afternoon into early evening may peak 35 to 40
kt.
.OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...
Monday: VFR. NW winds G25-30 kt into the evening.
Tuesday: VFR.
Wednesday: MVFR or lower with showers likely, especially in the
afternoon into the night. E wind gusts 15-20kt.
Thursday: MVFR or lower possible in showers. NE winds G20-30kt,
highest across southeastern Connecticut and eastern Long Island.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Small Craft Advisory conditions will start this morning with 25 to
30 kt gusts. Nearshore gusts could even be a few kt higher.
There will likely be a bit of a lull overnight before 25 kt
gusts are expected again on Monday. Thereafter, sub-SCA
conditions expected through Tuesday night. Seas on the ocean may
build to around 5 ft today into tonight.
With the approach of a frontal system during Wednesday, an easterly
flow will be increasing, and by late day SCA conditions are likely
to develop on the ocean waters. With the increased and persistent
east flow Wednesday night SCA conditions become likely across all
the forecast waters Wednesday night and continue into Thursday. A
brief period of near gale force gusts are possible on the ocean
waters east of Moriches Inlet Thursday.
As the low tracks northeast of the area Thursday night a northerly
flow develops and winds diminish west to east, falling below
advisory levels Thursday night. However, ocean seas are likely to
remain elevated through Friday, and possible into Friday
evening.
&&
.HYDROLOGY...
There are no hydrologic concerns through the week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT Monday for ANZ331-332-335-
338-340-345-350-353-355.
&&
$$
SYNOPSIS...MET/JT
NEAR TERM...JT/MW
SHORT TERM...JT
LONG TERM...MET
AVIATION...DS
MARINE...MET/JT
HYDROLOGY...MET/JT