AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1220 AM EDT Thu May 22 2025

.SYNOPSIS...
Low pressure approaches from the Mid-Atlantic overnight and 
passes just offshore Thursday into Thursday night. The low will 
weaken over the Canadian Maritimes this weekend, allowing high 
pressure to briefly build in for the beginning of next week.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
The forecast remains on track. The radar overall has continued
to fill in as any mid level dry air has given way to surge of
moisture from the SW.

As low pressure continues to approach from the south the rain 
should pick up in intensity overnight as an approaching low 
level jet enhances upward forcing. Hydrologic impacts look to be
limited, especially with the lack of convective potential 
- see the hydrology section for more details.

Breezy conditions with easterly winds for the overnight, 
particularly along the coast. Lows will range from the middle 
40s inland to around 50 for coastal areas.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM FRIDAY/...
The low level jet shifts through the area during the morning into 
early afternoon, taking the highest rainfall probabilities and 
intensity with it. The surface low will however still be nearby to 
our east in the evening, so rain chances continue across the area 
with the highest chances over the eastern zones. Chances then 
diminish during the late night hours with the low farther away to 
the NE.

Clouds and rainfall will hold temperatures in the 50s during the 
daytime with the northern zones likely not getting out the 40s.
NBM has been too warm in a cloudy/rainy regime lately, so went a
couple of degrees below it for highs. Low temperatures then 
mostly in the 40s. 15-25 mph ENE winds in the morning gradually 
back towards the north in the evening and diminish. Gusts 30-35 
mph for the coastal areas during the daytime.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
A broad upr lvl low will become established over the Northeast on 
Fri before translating into the maritimes by Sun. 

Fri will be cool across the area with highs in the 50s and lower 
60s. The cold pool aloft as well as cyclonic flow will allow for the 
generation of shwrs thru the day, especially in the aftn when lapse 
rates are steepest. With h85 temps dropping to around 1C, it would 
not be surprising to see some low topped tstms across the area with 
even some small hail. 

It will be even colder aloft on Sat, so continued chances for the 
generation of a few shwrs and low topped tstms. Drier air at the mid 
lvls attm may limit coverage, but could aid in the production of 
isold downburst wind gusts in convection. Better mixing on wly flow 
is progged to produce warmer daytime highs despite the colder 
airmass overall. Highs in the 60s per the NBM.

The fcst for Sun is dry, although the 12Z GFS has a shrtwv ripping 
thru the cwa producing more sct shwrs. Stuck with the blended 
approach of the NBM until this feature is resolved with more 
confidence. Warmer yet on Sun with highs in the upr 60s.

Warmer again on Memorial Day, although the current progs per the 
NBM still keep high temps aob normal in the low 70s. With weak high 
pres ridging across the cwa, generally dry attm, although the fcst 
brings in very slight chances by the end of the day srn areas as 
the next sys approaches.

The next sys is timed for Tue into Wed in the form of a Gulf primed 
weak low driven by the upr flow and sparked by convection over the 
cntrl CONUS. Stuck with the NBM, with another down-tick in temps due 
to the expected clouds and rain.

&&

.AVIATION /04Z THURSDAY THROUGH MONDAY/...
Weak low pressure will remain near the lower Great Lakes, while a 
second low develops near the southern Mid Atlantic coast. This 
second low will then move north, passing just south of Long Island 
on Thursday and just east Thursday night. 

MVFR cigs with some light rain and E-ENE flow 10-15G20kt should 
persist into this evening. As the low to the south develops, IFR 
cigs develop mainly after midnight and rain becomes moderate to 
locally heavy in intensity, while winds increase to 15-20G25kt and 
back NE. A return to MVFR looks to occur Thursday afternoon, with 
slow improvement toward VFR through the end of the TAF period.

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

Amendments likely mainly for changes in flight categories. 
Gusts may be more occasional than frequent through around 
daybreak.

.OUTLOOK FOR 00Z FRIDAY THROUGH SUNDAY...

Thursday night: Improvement to MVFR likely and potentially low end 
VFR. Winds backing NE-N 15G20-25kt. 

Friday: Chance of showers with MVFR cond at times. N winds 10-
15G20kt E of the NYC metros Thu evening. 

Saturday and Sunday: Mainly VFR. NW winds G15-18kt. 

Monday: VFR. 

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

.MARINE...
Small craft for all waters heading into tonight. Winds increase 
overnight with gales on the eastern ocean waters late at night, then 
over the eastern half of LI Sound as well as the eastern bays 
starting Thursday morning. Gale warning now in effect for these 
spots through Thursday afternoon. May need to extend the warning a 
few hours into the evening based on trends of a stronger low passing 
just east of the waters during Thurs evening. All current SCAs may 
needed to be extended by few hours as well. Gusts to 35 kt possible 
even over the ocean waters west of Fire Island inlet, but not 
widespread enough for warning consideration. 

A SCA will likely be needed on the ocean Fri-Sat, mainly for 
seas. All waters look to be blw SCA lvls Sun and Mon. Seas may 
then build on the ocean to SCA lvls late Tue.

&&

.MARINE...
Small craft for all waters heading into tonight. Winds increase 
overnight with gales on the eastern ocean waters late at night, then 
over the eastern half of LI Sound as well as the eastern bays 
starting Thursday morning. Gale warning now in effect for these 
spots through Thursday afternoon. May need to extend the warning a 
few hours into the evening based on trends of a stronger low passing 
just east of the waters during Thurs evening. All current SCAs may 
needed to be extended by few hours as well. Gusts to 35 kt possible 
even over the ocean waters west of Fire Island inlet, but not 
widespread enough for warning consideration. 

A SCA will likely be needed on the ocean Fri-Sat, mainly for 
seas. All waters look to be blw SCA lvls Sun and Mon. Seas may 
then build on the ocean to SCA lvls late Tue.

&&

.HYDROLOGY...
Total rainfall for this event through Thursday night is expected to 
range mostly 1-2 inches with up to 2.50 inches possible over eastern 
Long Island and Southeastern CT. The intensity and duration of the 
rain are however not high enough for flash flooding concerns. Only 
some minor nuisance urban related/poor drainage flooding will be 
possible, and mainly just during Thursday, so overall impacts should 
be low to none. 

No hydrologic impacts are expected Fri-Wed.

&&

.TIDES/COASTAL FLOODING...
A prolonged E-NE flow continues into Thursday afternoon, backing
N/NE Thursday afternoon and evening. This backing of winds
should help limit the magnitude of coastal flooding for most 
areas, but potentially enhance impacts along Peconic and 
Gardiners Bay and north shore of LI. 

Localized minor coastal flooding possible with the early Thu AM
high tide along western GSB.

The latest forecaster adjusted Stevens (75th percentile 
weighting), ETSS, PETSS STOFS guidance blend signals widespread 
minor coastal flooding for the south shore of Nassau County, the
twin forks of LI (localized moderate impacts possible for north
facing areas along the bayfront), and along much of LI Sound. 

Localized minor coastal flooding likely for NY/NJ harbor where 
winds will back to the N/NNE earlier. Magnitude of coastal 
flooding for central and eastern great South Bay, Moriches, and 
Shinnecock bays will depend on tidal piling trends, but looks to
be localized here.

For Fri evening high tide, coastal flooding looks to be more 
localized for the Fri eve high tide cycle, to southern Nassau 
and SW CT, in response to offshore flow and subsiding onshore 
swells. 

Potential for localized coastal flooding Sun into early next
week with approach of new moon, causing areas to need as little
as 1/4ft of tidal departure for minor coastal flooding. 

As far as shoreline impacts, along the north shore of the south
fork of Long Island, breaking waves of 1 to 3 ft may cause dune
erosion and localized washovers, as well as enhance splashover 
and flooding onto shoreline roads and properties. Along the 
ocean front and Orient Point, breaking waves of 4 to 6 ft on an 
east to west sweep will result in beach erosion and beach 
flooding during the times of high tide. Localized dune erosion 
is possible. Along the north shore of Long Island, breaking 
waves of 3 to 4 ft will cause dune erosion, localized washovers,
as well as enhance splashover and flooding onto shoreline roads
and properties.

&&

.CLIMATE...
Record minimum maximum (coldest high temperatures) are possible
for Thursday, May 22nd. Here are the records and forecast high
temperatures for the date:

NYC: 54/1894, forecast high: 53 
JFK: 55/1967, forecast high: 53
LGA: 57/2003, forecast high: 53
EWR: 56/2003, forecast high: 53 
BDR: 54/2005, forecast high: 51
ISP: 54/2003, forecast high: 54

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Coastal Flood Advisory from 6 PM to 10 PM EDT this evening for 
     CTZ009>012.
NY...Coastal Flood Advisory from 6 PM to 10 PM EDT this evening for 
     NYZ071-073-078-176-177.
     Coastal Flood Advisory from 2 PM this afternoon to 11 PM EDT 
     this evening for NYZ079>081-179.
     Coastal Flood Advisory from 2 PM this afternoon to 7 PM EDT 
     this evening for NYZ178.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EDT early this morning for 
     ANZ331-332-340.
     Gale Warning from 6 AM this morning to 6 PM EDT this evening 
     for ANZ331-332-340.
     Small Craft Advisory until 6 PM EDT this evening for ANZ335-
     338-345.
     Gale Warning until 6 PM EDT this evening for ANZ350-353.
     Small Craft Advisory until 6 AM EDT Friday for ANZ355.

&&

$$

SYNOPSIS...JMC/JC
NEAR TERM...JC/JE
SHORT TERM...JC
LONG TERM...JMC
AVIATION...JP
MARINE...JMC/JC
HYDROLOGY...JMC/JC
TIDES/COASTAL FLOODING...
CLIMATE...