Alert archive / New York / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 3, NWS New York, NY

May 20, 2026Suffolk County, New York

NWS New York, NY issued this severe thunderstorm warning at May 20, 2026, 4:32 PM EDT for Suffolk County, New York. It was in force for 32 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
May 20, 2026, 4:32 PM EDT (20:32 UTC)
Expired
May 20, 2026, 5:04 PM EDT
In force
32 min
Issued by
NWS New York, NY
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Suffolk County, NY

The radar

The Brookhaven radar (KOKX), 33 km from the middle of the area, began a volume at 20:31 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
May 20, 4:42 PM EDTTSTM WND DMG1 Nne East Northport, NYTree and branches down on Soundview Avenue in East Northport with time of report estimated by radar.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 10 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 20, 2:10 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 8.5 hours before the alert went out and 33 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 12:00Z on 2026-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 31 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2026-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
31 J/kg
Mixed-layer CIN
-279 J/kg
Mixed-layer LCL
1524 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
80 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

482 
WUUS51 KOKX 202032
SVROKX
NYC103-202115-
/O.NEW.KOKX.SV.W.0003.260520T2032Z-260520T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service New York NY
432 PM EDT Wed May 20 2026

The National Weather Service in Upton NY has issued a

* Severe Thunderstorm Warning for...
  West central Suffolk County in southeastern New York...

* Until 515 PM EDT.

* At 432 PM EDT, a severe thunderstorm was located over Northport,
  moving east at 30 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Minor hail damage to vehicles is possible. Expect wind 
           damage to trees and power lines.

* This severe thunderstorm will be near...
  Stony Brook around 445 PM EDT.
  Port Jefferson around 450 PM EDT.
  Mount Sinai around 455 PM EDT.
  Rocky Point around 505 PM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4087 7345 4095 7344 4094 7342 4097 7339
      4094 7334 4095 7329 4092 7322 4093 7317
      4097 7317 4099 7312 4098 7306 4098 7291
      4085 7296
TIME...MOT...LOC 2032Z 263DEG 28KT 4094 7332 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

JT
2 follow-up statements
037 
WWUS51 KOKX 202052
SVSOKX

Severe Weather Statement
National Weather Service New York NY
452 PM EDT Wed May 20 2026

NYC103-202115-
/O.CON.KOKX.SV.W.0003.000000T0000Z-260520T2115Z/
Suffolk NY-
452 PM EDT Wed May 20 2026

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EDT
FOR WESTERN SUFFOLK COUNTY...

At 452 PM EDT, a severe thunderstorm was located over Port Jefferson,
moving east at 30 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect damage to trees and power lines.

This severe storm will be near...
  Port Jefferson and Mount Sinai around 455 PM EDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4087 7327 4093 7327 4093 7325 4092 7322
      4093 7317 4095 7317 4096 7294 4085 7296
TIME...MOT...LOC 2052Z 263DEG 28KT 4096 7311 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

JT
561 
WWUS51 KOKX 202104
SVSOKX

Severe Weather Statement
National Weather Service New York NY
504 PM EDT Wed May 20 2026

NYC103-202113-
/O.CAN.KOKX.SV.W.0003.000000T0000Z-260520T2115Z/
Suffolk NY-
504 PM EDT Wed May 20 2026

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN SUFFOLK COUNTY IS
CANCELLED...

The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.  However, gusty winds and
heavy rain are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 900 PM EDT for
southeastern New York.

&&

LAT...LON 4087 7327 4093 7327 4093 7325 4092 7322
      4093 7317 4095 7317 4096 7294 4085 7296
TIME...MOT...LOC 2102Z 263DEG 28KT 4097 7299 

$$

JT

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS New York, NY wrote its last area forecast discussion before this severe thunderstorm warning went out at May 20, 2:40 PM EDT, 1 hour 52 minutes earlier. Its key messages:

  • 1) A Heat Advisory remains in effect for NYC and northeast New Jersey as hot weather continues through this afternoon. 2) Scattered strong to severe thunderstorms are possible this afternoon and evening, followed by lingering showers tonight into early Thursday. 3) Unsettled with periods of showers expected for the upcoming holiday weekend along with a much cooler airmass over the region.
Area forecast discussion, May 20, 2:40 PM EDT, 1 hour 52 minutes before
Area Forecast Discussion
National Weather Service New York NY
240 PM EDT Wed May 20 2026

.WHAT HAS CHANGED...
A Severe Thunderstorm Watch has been issued area-wide through
8PM this evening.

&&

.KEY MESSAGES...
1) A Heat Advisory remains in effect for NYC and northeast New
Jersey as hot weather continues through this afternoon.

2) Scattered strong to severe thunderstorms are possible this
afternoon and evening, followed by lingering showers tonight into
early Thursday.

3) Unsettled with periods of showers expected for the upcoming
holiday weekend along with a much cooler airmass over the
region.

&&

.DISCUSSION...
.KEY MESSAGE 1...
No changes were made to the heat advisory for the NYC metro and NE
NJ which remains in effect until 8pm.

Temperatures and heat indices have already warmed into the 90s with
ample sunshine. Cloud cover will increase ahead of a cold front this
afternoon and evening with showers and thunderstorms forecasted.
This will bring an end to the heat, likely earlier than the 8pm end
time of the Heat Advisory.

.KEY MESSAGE 2...
A cold front, currently draped across Central NY into
central/western PA, will move across the region this afternoon and
evening. The front will serve as a mechanism to develop showers
along with scattered thunderstorms in the afternoon and evening.

A Severe Thunderstorm Watch has been issued area-wide through 8PM.
SPC has upgraded the southern two-thirds of the area to a slight
risk for severe thunderstorms. The main concern is for damaging wind
gusts with an additional more isolated risk for large hail. Timing
for the severe thunderstorm potential continues to be from 2pm-8pm.

2-5pm appears to be the prime window for isolated convection to pop
up across the area with ample heating and possible triggers being
local sea breeze boundaries. Many 12Z/15Z CAMs bring through a
cluster or line of thunderstorms ahead of the cold front which will
follow the earlier isolated convection. Timing for this appears to
be 5-8pm, tracking west to east, then losing intensity across
eastern portions of the area 8-10pm.

Mesoanalysis shows a good SBCAPE environment 1500-2500 J/kg with
these storms. However, mid level lapse rates (6-6.5 C) and bulk
shear (25-40kt) appear more modest. DCAPE is being analyzed very
strong for the area around 1000-1100 J/kg across NYC and Long
Island, which reinforces concern for damaging wind gusts. Based on
mesoanalysis, the areas of most concern for damaging wind appear to
be Union/Essex/Hudson NJ, NYC metro, Nassau county and western
Suffolk county.

PWATs are 1.6-2 inches, which is above the max moving average based
on SPC's Sounding Climatology Page. Rain rates could be
0.75/1.25"/hr with isolated higher rainfall rates around 2"/hr,
possible. 12Z HREF gives a 20-40% 10km neighborhood probability of
rainfall rates reaching or exceeding 1"/hr across the southern half
of the CWA. The 12Z REFS are 20-40% across western Long Island and
NE NJ, with parts of NYC higher around 50-60% 10-km neighborhood
probability 1"/hr.

The good news is storms will be moving west to east at a good clip.
Given the risk for heavier downpours in these thunderstorms,
isolated nuisance flooding is possible particularly across southern
portions of the area, including NYC. However, widespread or major
flooding is not anticipated.

Showers will likely linger the first half of the night near the
coast as the front works offshore. There may also be some
redevelopment of showers late tonight into early Thursday morning as
a weak wave of low pressure develops along the front. The low
pressure is tied to a passing jet streak to our north, associated
with a broad trough over Northern New England and southeast Canada.
There is still some uncertainty with this feature as some of the
model guidance keeps the showers just south of Long Island.

Conditions should dry out Thursday afternoon, but lingering cloud
cover may persist through much of the day. Best chance for some
clearing looks to be well northwest of the NYC metro.

Daytime temperatures on Thursday will only be in the 60s, 20-30
degrees cooler than Wednesday. Daytime temperatures on Thursday will
only be in the low/mid 60s, 20-30 degrees cooler than Wednesday.

.KEY MESSAGE 3...
The end of the week will remain dry and much cooler. The dry
period will be short-lived as unsettled weather with periods of
showers looks likely for the upcoming holiday weekend. The
frontal boundary that moves through today/Wednesday will remain
to our south with multiple disturbances/waves of low pressure
moving along it through the weekend. Moisture from these systems
will overrun high pressure to our north and east.

The main challenge for this period is timing when the most
widespread shower activity will occur. The highest probabilities
currently are from late Friday through early Sunday. However, there
is still some uncertainty, especially if the surface ridging from
the high is stronger. This would help suppress the showers a bit
further south, with at least the northern half of the region seeing
less rainfall. Chances for showers continue late Sunday into
Memorial Day as additional energy may pass to west or northwest.

Otherwise, will remain mostly cloudy through the weekend with
temperatures likely running below normal for late May in the low to
mid 60s. Nighttime temperatures should be in the 50s. The frontal
boundary may get pushed further south by next Tuesday, which could
help lower any chance for showers.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A cold front moves across this evening. The front slowly pushes
south of the region late tonight into Thursday with high pressure
slowly moving towards the area from the Great Lakes.

Showers and thunderstorms develop and move in through late this
afternoon. They continue early this evening. Some thunderstorms
could be severe with main threats being strong wind gusts up to 40-
50 kt and possible large hail. Periodic MVFR or lower will be
possible.

Thunderstorm chances lower by mid to late evening with most activity
south of Long Island. Showers do remain though for much of the
terminals tonight, becoming more periodic late tonight into
Thursday. Periodic MVFR will be possible.

Outside of the MVFR or lower possible, mainly VFR conditions are
expected through the TAF period. Winds mainly westerly flow this
afternoon near 10-15 kt with gusts near 20-25 kt. Gusts subside
tonight with flow becoming more northerly near 10 kt. Winds become
more NE Thursday without much change in wind speed.

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

* Timing of showers and thunderstorms could be off by 1-3 hours
  compared to TAF.

* Categorical changes in TAF could be off by a few hours.

.OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY...

Thursday: MVFR or lower conditions possible early for coastal
terminals and NYC terminals at times with a chance of showers
in the afternoon. Mainly VFR Thursday night.

Friday: Possible showers and MVFR conditions late at night.

Saturday: MVFR or lower with showers. E-NE wind gusts 15-20 kt.

Sunday: MVFR or lower with showers. E-NE wind gusts 15-20 kt during
the day.

Monday: Chance of MVFR or lower with showers.

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

&&

.MARINE...
A Small Craft Advisory over ocean waters has been expired early.
Waves are below 5 ft. Its possible waves could return above 5 ft
with the front and any stronger showers or thunderstorms this
evening into early tonight. However, should this occur, it would
likely be too brief and local for a widespread SCA issuance.

Winds and waves will remain below SCA levels through Saturday
morning. Saturday morning into Sunday winds and waves may once again
reach SCA levels, while waves on ocean waters could remain elevated
into the start of next week.

&&

.CLIMATE...
Record High Minimum Temperatures:

May 20:
KEWR: 72/1996
KBDR: 61/2019
KNYC: 74/1996
KLGA: 77/1996
KJFK: 63/1996
KISP: 62/1996

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Heat Advisory until 8 PM EDT this evening for NYZ072>075-176-
     178.
NJ...Heat Advisory until 8 PM EDT this evening for NJZ002-004-006-
     103>108.
MARINE...None.

&&

DISCUSSION...JM/BR
AVIATION...JM
MARINE...JM/BR
Hazardous weather outlook, May 20, 2:43 PM EDT, 1 hour 49 minutes before
Hazardous Weather Outlook
National Weather Service New York NY
243 PM EDT Wed May 20 2026

NJZ002-004-006-103>108-NYZ072>075-176-178-211845-
Western Passaic-Eastern Passaic-Hudson-Western Bergen-Eastern Bergen-
Western Essex-Eastern Essex-Western Union-Eastern Union-
New York (Manhattan)-Bronx-Richmond (Staten Island)-Kings (Brooklyn)-
Northern Queens-Southern Queens-
243 PM EDT Wed May 20 2026

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...
...SEVERE THUNDERSTORM WATCH 235 IN EFFECT UNTIL 9 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for northeast New Jersey and
southeast New York.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Heat Advisory.
   Severe Thunderstorm Watch.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Hazardous weather is not expected at this time that would meet NWS
warning criteria.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed.

&&

This Hazardous Weather Outlook provides a summary of potential
widespread hazardous weather events that may reach NWS warning
criteria. Most long fused NWS watches, warnings, and advisories in
effect are highlighted.

Please refer to the latest NWS forecasts for weather not meeting NWS
warning criteria.

ANZ345-CTZ005>012-NYZ067>071-078>081-177-179-211845-
South Shore Bays from Jones Inlet through Shinnecock Bay-
Northern Fairfield-Northern New Haven-Northern Middlesex-
Northern New London-Southern Fairfield-Southern New Haven-
Southern Middlesex-Southern New London-Orange-Putnam-Rockland-
Northern Westchester-Southern Westchester-Northwest Suffolk-
Northeast Suffolk-Southwest Suffolk-Southeast Suffolk-
Northern Nassau-Southern Nassau-
243 PM EDT Wed May 20 2026

...SEVERE THUNDERSTORM WATCH 235 IN EFFECT UNTIL 9 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for Atlantic coastal waters,
southern Connecticut and southeast New York.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Severe Thunderstorm Watch.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Hazardous weather is not expected at this time that would meet NWS
warning criteria.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed.

&&

This Hazardous Weather Outlook provides a summary of potential
widespread hazardous weather events that may reach NWS warning
criteria. Most long fused NWS watches, warnings, and advisories in
effect are highlighted.

Please refer to the latest NWS forecasts for weather not meeting NWS
warning criteria.

ANZ380-383-385-211845-
Waters from Moriches Inlet NY to Montauk Point NY from 20 to 60 nm-
Waters from Fire Island Inlet NY to Moriches Inlet NY from 20 to
60 nm-
Waters from Sandy Hook NJ to Fire Island Inlet NY from 20 to 60 nm-
243 PM EDT Wed May 20 2026

This Hazardous Weather Outlook is for Atlantic coastal waters.

.DAY ONE...This afternoon and tonight.

Hazardous weather is not expected at this time that would meet NWS
warning criteria.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Hazardous weather is not expected at this time that would meet NWS
warning criteria.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

&&

This Hazardous Weather Outlook provides a summary of potential
widespread hazardous weather events that may reach NWS warning
criteria. Most long fused NWS watches, warnings, and advisories in
effect are highlighted.

Please refer to the latest NWS forecasts for weather not meeting NWS
warning criteria.

ANZ331-332-335-338-340-350-353-355-211845-
Long Island Sound East of New Haven CT/Port Jefferson NY to the
Mouth of the Connecticut River-
Long Island Sound East of the Mouth of the Connecticut River-
Long Island Sound West of New Haven CT/Port Jefferson NY-
New York Harbor-Peconic and Gardiners Bays-
Moriches Inlet NY to Montauk Point NY out 20 NM-
Fire Island Inlet NY to Moriches Inlet NY out 20 NM-
Sandy Hook NJ to Fire Island Inlet NY out 20 NM-
243 PM EDT Wed May 20 2026

...SEVERE THUNDERSTORM WATCH 235 IN EFFECT UNTIL 9 PM EDT THIS
EVENING...

This Hazardous Weather Outlook is for Atlantic coastal waters.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Severe Thunderstorm Watch.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Hazardous weather is not expected at this time that would meet NWS
warning criteria.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

&&

This Hazardous Weather Outlook provides a summary of potential
widespread hazardous weather events that may reach NWS warning
criteria. Most long fused NWS watches, warnings, and advisories in
effect are highlighted.

Please refer to the latest NWS forecasts for weather not meeting NWS
warning criteria.

The office that day

Everything else NWS New York, NY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 20, 4:00 PM EDTSpecial Marine WarningOKX45 min
May 20, 4:35 PM EDTSpecial Weather StatementOKXWestchester25 min
May 20, 4:48 PM EDTSpecial Marine WarningOKX57 min
May 20, 5:20 PM EDTSpecial Weather StatementOKXRockland, Westchester40 min
May 20, 5:25 PM EDTSevere Thunderstorm WarningOKXWestchester50 min
May 20, 5:45 PM EDTSpecial Weather StatementOKXSuffolk45 min
May 20, 6:07 PM EDTSevere Thunderstorm WarningOKXKings, New York, Richmond53 min
May 20, 6:15 PM EDTSpecial Marine WarningOKX45 min
May 20, 6:25 PM EDTSpecial Marine WarningOKX65 min
May 20, 6:36 PM EDTSpecial Weather StatementOKXNassau39 min
May 20, 6:43 PM EDTSpecial Marine WarningOKX62 min
May 20, 6:51 PM EDTSevere Thunderstorm WarningOKXKings, Nassau, Queens, Richmond39 min
May 20, 6:57 PM EDTAreal Flood AdvisoryOKXKings, Nassau, New York, Queens, Richmond3 hr
May 20, 7:04 PM EDTSpecial Marine WarningOKX56 min
May 20, 7:30 PM EDTSpecial Weather StatementOKXNassau, Queens45 min
May 20, 7:58 PM EDTSpecial Marine WarningOKX32 min

Nearby

Severe Thunderstorm Warnings in New York, 2026Every severe thunderstorm warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.