New York, 2021

Flash Flooding and Flood in New York, August 22 to 23, 2021

August 22 to 23, 2021 · NWS OKX · 18 events in 6 counties and zones

Rainfall from Tropical Storm Henri resulted in widespread flash flooding across southeastern New York, particularly portions of the Lower Hudson Valley. With a tropical airmass in place (precipitable water values greater than 2 inches), rainfall totals generally ranged from 2-5 inches, with this rain coming in addition to the 2-5 inches that fell during the predecessor rainfall event the night…

Where it happened

Every event with a place to put it. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
18

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS OKX wrote it up.

Rainfall from Tropical Storm Henri resulted in widespread flash flooding across southeastern New York, particularly portions of the Lower Hudson Valley. With a tropical airmass in place (precipitable water values greater than 2 inches), rainfall totals generally ranged from 2-5 inches, with this rain coming in addition to the 2-5 inches that fell during the predecessor rainfall event the night before. This resulted in widespread rainfall amounts of 3-6 inches in many locations over a 24-36 hour period. The ASOS in Central Park recorded an additional 3.39 inches of rain, for a total of 7.84 inches across the two days.

What forecasters said that day

The local office's own words before the first event, 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 the first event at Aug 22, 1:03 PM EST, 52 minutes earlier.

Area forecast discussion, Aug 22, 1:03 PM EST, 52 minutes before
Area Forecast Discussion
National Weather Service New York NY
203 PM EDT Sun Aug 22 2021

.SYNOPSIS...
Tropical Storm Henri just off the CT/RI coast will be moving inland
this morning with impacts likely across parts of the local area
today through Monday. A stretch of hot weather is possible for
the middle of next week, followed by a cold frontal passage on
Friday.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
**TROPICAL STORM CONDITIONS EXPECTED ACROSS PORTIONS OF LONG ISLAND AND
 SOUTHERN CONNECTICUT**

Bands of moderate to heavy rain continue to move across portions
of the forecast area. One moving east across southwestern
Connecticut and another moving south across western Long Island
and portions of New York City. Another band looks to be
developing across eastern portions of the Lower Hudson Valley as
well. These bands will continue to dump heavy rain as Henri
slowly moves northwest into southern New England.

Tropical storm force winds are expected along the south shore,
eastern Long Island and across southeast Connecticut, especially
from mid morning onward, with the strongest winds across the
Twin Forks and southeast coastal Connecticut. The highest winds
will likely occur before the middle of this afternoon. The
heaviest of the rain is expected to be to the west of Henri as
the system interacts with an upper level shortwave.
Additionally, some higher amounts can be expected across some of
the higher terrain well inland. The period of heaviest rain is
between 8 am and 2 pm Sunday, where 3 to 6 inches or more may
fall over much of Suffolk County. A flood watch remains in
effect for the entire region with moderate potential for flash
flooding and river flooding today into tonight.

Storm surge inundation is also a concern and there is potential
for life-threatening storm surge along the immediate shore of
Long Island, Southern Connecticut, and the Western Long Island
Sound. The timeline of impacts looks to be this morning through
this evening, with the storm weakening as it moves northward.
Additionally, heavy rain that may occur during times of high
tide could exacerbate flooding along these areas, as there will
be a combination of coastal and fresh water flooding.

Finally, there is the potential for an isolated tornadoes to
move through as Henri makes its approach and landfall. The Storm
Prediction Center has placed southeast Connecticut and eastern
Long Island in a marginal risk for severe storms. Large helicity
values are noted in the models, however surface based instability
could the limiting factor and the reason that the possibility of
tornadoes will not be more widespread.

Please refer to the National Hurricane Center and Hurricane
Local Statement for the official forecast track information.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
Henri will track northwest into southern New England Sunday into
Sunday night, shifting the heavy rain into southwest Connecticut
and the Lower Hudson Valley during through Monday. A widespread
rainfall of 5 to 10 inches is possible as Henri losses forward
speed as it begins to be absorbed into the upper level trough.
Upper level southerly jet extending south of the region into the
Atlantic will help provide a tropical rich moisture source with
layer precipitable waters remaining near 2 inches tonight into
early Monday. The flood watch for the entire region has been
extended in time until 8 PM EDT Monday night to cover the
lingering rainfall into Monday as well as residual runoff and
river flooding anticipated.

The day 2 outlook for WPC has the area in a slight risk for
excessive rainfall. The potential is there for long fused minor
river flooding for down stream rivers such as the Passaic,
Saddle, and Housatonic Rivers. This situation will have to be
monitored throughout the day Monday for updates as much is
dependent on the exact location of heaviest rainfall.

Rain should come to an end late Monday night once the combined
upper level trough and Henri shift northeast into New England.
South winds become more westerly to southwesterly with overcast
skies beginning to scatter through the evening.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
The focus turns to the heat Tuesday through Thursday. H85 temps
warm to around 18-19C in the Tue-Thu period as a ridge builds
into central New York state. The NBM looked a little low based
on these numbers on Wed and Thu, so for those two days went with
the MEX guidance for highs. There is still room for upward
adjustment temp wise. Dewpoints are progged to be in the upr 60s
to low 70s thru the period, yielding heat indices in the heat
advy range for much of the area based on the 2-day criteria with
much of the area being between 93 to 97 heat indices. Moreover
100 degree heat indices are also possible for some areas Wed and
Thu.

A cold front appears on track for late Fri with shwrs and tstms
possible as rain chances increase late into the week. Moisture
may linger into the weekend as the front stalls. Slight rain
chances expected both Saturday and Sunday.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
Henri will track across CT this aftn, then into Northern New
England on Mon.

Rain, heavy at times, will continue this aftn. Cigs have been
around 1000 ft so kept IFR in the TAFs with rainfall increasing
which is expected to help lower cigs, particularly NYC arpts.
Conditions improve late tngt into Mon as the sys tracks nwd and
weakens, especially east of the low center which will be mainly
dry.

Winds will continue to back into this eve, then direction will
level out aft 2Z as the storm stalls. As the low changes
direction and pulls away, winds will back more sly during the
day on Mon.

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

Cigs may remain MVFR thru this eve, although confidence was too
low to include in the TAFs. Winds will continue to be updated in
subsequent TAFs based on the strength and track of Henri.

Additional shwrs and tstms may impact operations on Mon, but
timing and coverage is too uncertain attm.

.OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY...
.Mon...MVFR or lower at times with shwrs and tstms.
.Tue...VFR.
.Wed...VFR.
.Thu...Mainly VFR but chances for aftn and eve tstms.
.Fri...Mainly VFR but chances for tstms late with a cold front.

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

&&

.MARINE...
Dangerous conditions develop on the waters through today due to
Henri. Tropical Storm Warnings in effect for all waters.
Conditions should begin to improve tonight into Monday. Please
refer to the National Hurricane Center for the official forecast
track information.

Waves are expected to build to anywhere from 10 to as much as 20
ft on the ocean waters this morning, with the highest waves
across the eastern ocean zone. Waves across the central and
eastern could build to 10 and 11 ft respectively. Up to 8 ft
waves are possible in the Gardiner's Bay. Waves and seas
eventually decrease tonight into early Monday.

Seas may remain abv 5 ft on the ocean Mon, Tue, and perhaps Wed.
Winds may be close to sca lvls on all waters Mon depending on the
position of Henri. All waters should be blw sca criteria for Thu and
Fri.

&&

.HYDROLOGY...
A Flood Watch continues for the entire area and now extends
through Monday evening. Hydrologic impacts today through Monday
will depend on the track and intensity of Henri. There is the
potential of a widespread 5-10 inches of rainfall today through
Monday evening for the Lower Hudson Valley and parts of Southern
Connecticut and 3 to 6 inches for elsewhere in associated with
Henri. Locally higher amounts are possible. Flash flooding is
possible, especially across NYC, Long Island and Connecticut. NYC
has already picked up 4 to 6 inches in some areas due to a
predecessor rainfall event last night.

No hydrologic impacts are expected Tue-Thu.

&&

.TIDES/COASTAL FLOODING...
There is potential for life threatening storm surge from Henri
across portions of the Long Island coast and southern Connecticut
coast today. Storm surge warnings are in effect.

Dangerous rip currents are expected through Monday due to
Tropical System Henri.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Flood Watch through Monday evening for CTZ005>012.
     Tropical Storm Warning for CTZ005>012.
NY...Flood Watch through Monday evening for NYZ067>075-078>081-
     176>179.
     Tropical Storm Warning for NYZ070-071-078>081-177-179.
     High Rip Current Risk through Monday evening for NYZ075-080-
     081-178-179.
NJ...Flood Watch through Monday evening for NJZ002-004-006-103>108.
MARINE...Tropical Storm Warning for ANZ331-332-335-340-345-350-353-355.
&&

SYNOPSIS...JMC/DJ
NEAR TERM...DJ/JM/JP
SHORT TERM...DJ/JM
LONG TERM...JMC
AVIATION...JMC
MARINE...DJ/JP
HYDROLOGY...DJ/JP
TIDES/COASTAL FLOODING...
Hazardous weather outlook, Aug 22, 10:58 AM EST, 2 hours 57 minutes before
Hazardous Weather Outlook
National Weather Service New York NY
1158 AM EDT Sun Aug 22 2021

NJZ002-004-006-103>108-NYZ067>069-072-074-231600-
Western Passaic-Eastern Passaic-Hudson-Western Bergen-Eastern Bergen-
Western Essex-Eastern Essex-Western Union-Eastern Union-Orange-
Putnam-Rockland-New York (Manhattan)-Richmond (Staten Island)-
1158 AM EDT Sun Aug 22 2021

...FLOOD WATCH IN EFFECT THROUGH MONDAY 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.

   Flood Watch.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

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

   Flood Watch.

.SPOTTER INFORMATION STATEMENT...

Spotter activation according to Standard Operating Procedures is
requested and appreciated.

&&

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.

CTZ009>012-NYZ071-078-079-177-231600-
Southern Fairfield-Southern New Haven-Southern Middlesex-
Southern New London-Southern Westchester-Northwest Suffolk-
Northeast Suffolk-Northern Nassau-
1158 AM EDT Sun Aug 22 2021

...FLOOD WATCH IN EFFECT THROUGH MONDAY EVENING...
...STORM SURGE WARNING IN EFFECT...
...TROPICAL STORM WARNING IN EFFECT...

This Hazardous Weather Outlook is for 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.

   Flood Watch.
   Storm Surge Warning.
   Tropical Storm Warning.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

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

   Flood Watch.
   Storm Surge Warning.
   Tropical Storm Warning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation according to Standard Operating Procedures is
requested and appreciated.

&&

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.

CTZ005>008-NYZ070-231600-
Northern Fairfield-Northern New Haven-Northern Middlesex-
Northern New London-Northern Westchester-
1158 AM EDT Sun Aug 22 2021

...FLOOD WATCH IN EFFECT THROUGH MONDAY EVENING...
...TROPICAL STORM WARNING IN EFFECT...

This Hazardous Weather Outlook is for 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.

   Flood Watch.
   Tropical Storm Warning.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

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

   Flood Watch.
   Tropical Storm Warning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation according to Standard Operating Procedures is
requested and appreciated.

&&

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.

NYZ073-176-231600-
Bronx-Northern Queens-
1158 AM EDT Sun Aug 22 2021

...FLOOD WATCH IN EFFECT THROUGH MONDAY EVENING...
...STORM SURGE WARNING IN EFFECT...

This Hazardous Weather Outlook is for 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.

   Flood Watch.
   Storm Surge Warning.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

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

   Flood Watch.
   Storm Surge Warning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation according to Standard Operating Procedures is
requested and appreciated.

&&

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.

NYZ075-178-231600-
Kings (Brooklyn)-Southern Queens-
1158 AM EDT Sun Aug 22 2021

...FLOOD WATCH IN EFFECT THROUGH MONDAY EVENING...
...HIGH RIP CURRENT RISK IN EFFECT THROUGH MONDAY EVENING...

This Hazardous Weather Outlook is for 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.

   High Rip Current Risk.
   Flood Watch.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

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

   High Rip Current Risk.
   Flood Watch.

.SPOTTER INFORMATION STATEMENT...

Spotter activation according to Standard Operating Procedures is
requested and appreciated.

&&

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.

NYZ080-179-231600-
Southwest Suffolk-Southern Nassau-
1158 AM EDT Sun Aug 22 2021

...FLOOD WATCH IN EFFECT THROUGH MONDAY EVENING...
...HIGH RIP CURRENT RISK IN EFFECT THROUGH MONDAY EVENING...
...TROPICAL STORM WARNING IN EFFECT...

This Hazardous Weather Outlook is for 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.

   High Rip Current Risk.
   Flood Watch.
   Tropical Storm Warning.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

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

   High Rip Current Risk.
   Flood Watch.
   Tropical Storm Warning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation according to Standard Operating Procedures is
requested and appreciated.

&&

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.

NYZ081-231600-
Southeast Suffolk-
1158 AM EDT Sun Aug 22 2021

...FLOOD WATCH IN EFFECT THROUGH MONDAY EVENING...
...HIGH RIP CURRENT RISK IN EFFECT THROUGH MONDAY EVENING...
...STORM SURGE WARNING IN EFFECT...
...TROPICAL STORM WARNING IN EFFECT...

This Hazardous Weather Outlook is for 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.

   High Rip Current Risk.
   Flood Watch.
   Tropical Storm Warning.
   Storm Surge Warning.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

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

   High Rip Current Risk.
   Flood Watch.
   Tropical Storm Warning.
   Storm Surge Warning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation according to Standard Operating Procedures is
requested and appreciated.

&&

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.

ANZ331-332-335-340-345-350-353-355-231600-
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-
Peconic and Gardiners Bays-
South Shore Bays from Jones Inlet through Shinnecock Bay-
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-
1158 AM EDT Sun Aug 22 2021

...TROPICAL STORM WARNING IN EFFECT...

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.

   Tropical Storm Warning.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

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

   Tropical Storm Warning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation according to Standard Operating Procedures is
requested and appreciated.

&&

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.

ANZ338-231600-
New York Harbor-
1158 AM EDT Sun Aug 22 2021

This Hazardous Weather Outlook is for Atlantic coastal waters.

.DAY ONE...This afternoon and tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

No hazardous weather is expected at this time that would meet NWS
warning criteria.

.SPOTTER INFORMATION STATEMENT...

Spotter activation according to Standard Operating Procedures is
requested and appreciated.

&&

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.

In the hours before

Local storm report, Aug 22, 1:21 PM EST, 34 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NEW YORK NY
221 PM EDT SUN AUG 22 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1141 AM     TROPICAL STORM   BRIDGEHAMPTON           40.94N 72.30W
08/22/2021                   SUFFOLK            NY   PUBLIC

            TREE LIMBS DOWN ON WIRES WITH POWER OUTAGES
            REPORTED.

&&

JMC
Local storm report, Aug 22, 1:22 PM EST, 33 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NEW YORK NY
222 PM EDT SUN AUG 22 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1135 AM     TROPICAL STORM   OLD SAYBROOK            41.29N 72.37W
08/22/2021                   MIDDLESEX          CT   PUBLIC

            TREE DOWN ON POWERLINES.

&&

JMC
Local storm report, Aug 22, 1:28 PM EST, 27 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NEW YORK NY
228 PM EDT SUN AUG 22 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0103 PM     TROPICAL STORM   LISBON                  41.58N 72.02W
08/22/2021                   NEW LONDON         CT   PUBLIC

            UPROOTED TREES ON POWER LINES.

&&

JMC
Local storm report, Aug 22, 1:29 PM EST, 26 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NEW YORK NY
229 PM EDT SUN AUG 22 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0203 PM     TROPICAL STORM   GALES FERRY             41.46N 72.09W
08/22/2021                   NEW LONDON         CT   PUBLIC

            TREE DOWN ON HOUSE

&&

JMC
Local storm report, Aug 22, 1:37 PM EST, 18 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NEW YORK NY
237 PM EDT SUN AUG 22 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1154 AM     TROPICAL STORM   1 SSW DARIEN            41.04N 73.48W
08/22/2021                   ANZ335             CT   PUBLIC

            PEAR TREE POINT BEACH PARKING LOT UNDER
            WATER.

&&

JMC
Local storm report, Aug 22, 1:43 PM EST, 12 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NEW YORK NY
243 PM EDT SUN AUG 22 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1154 AM     COASTAL FLOOD    1 SSW DARIEN            41.04N 73.48W
08/22/2021                   ANZ335             CT   PUBLIC

            CORRECTS PREVIOUS TROPICAL STORM REPORT FROM
            1 SSW DARIEN. PEAR TREE POINT BEACH PARKING
            LOT UNDER WATER.

&&

JMC

The radar

The Brookhaven radar (KOKX), 81 km away, was scanning. The volume nearest the first event began at 18:54 UTC.

Open the radar archive at this moment

Event by event

17 flash flood, 1 flood. Local standard time, as filed.

Flash Flood, Westchester

When
August 22, 1:55 PM EST to 4:45 PM EST
Where
Westchester County, 0.93 mi ESE of Elmsford to 0.96 mi ESE of Elmsford
Cause
Heavy Rain
Reported by
Department of Highways
Coordinates
41.044, -73.804

Both directions of NY 119 (Tarrytown Road) were closed due to flooding at Knollwood Road in Elmsford.

Flash Flood, Westchester

When
August 22, 1:59 PM EST to 4:45 PM EST
Where
Westchester County, 0.58 mi NW of Valhalla to 0.83 mi NW of Valhalla
Cause
Heavy Rain
Reported by
Department of Highways
Coordinates
41.087, -73.787

The Taconic State Parkway was closed in both directions in Hawthorne due to flooding between Stevens Avenue and Commerce Street.

Flash Flood, Westchester

When
August 22, 2:22 PM EST to 4:45 PM EST
Where
Westchester County, 1.13 mi NW of Thornwood to 1.16 mi NW of Thornwood
Cause
Heavy Rain
Reported by
Department of Highways
Coordinates
41.132, -73.795

The Saw Mill River Parkway was closed in both directions due to flooding at Manville Road in Pleasantville.

Flash Flood, Westchester

When
August 22, 2:24 PM EST to 4:45 PM EST
Where
Westchester County, 0.52 mi E of Elmsford to 0.89 mi E of Elmsford
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
41.050, -73.810

The Sprain Brook Parkway was closed northbound in Elmsford due to flooding.

Flash Flood, Nassau

When
August 22, 2:30 PM EST to 4:55 PM EST
Where
Nassau County, 0.32 mi NNE of South Vly Stream to 0.36 mi N of South Vly Stream
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
40.655, -73.699

Rockaway Avenue in Valley Stream was closed due to flooding.

Flash Flood, Westchester

When
August 22, 2:32 PM EST to 4:45 PM EST
Where
Westchester County, 0.23 mi NNW of Elmsford to 0.41 mi NNW of Elmsford
Cause
Heavy Rain
Reported by
Department of Highways
Coordinates
41.053, -73.822

The northbound lanes of the Saw Mill River Parkway in Elmsford were closed due to flooding at West Main Street.

Flash Flood, Westchester

When
August 22, 2:34 PM EST to 4:45 PM EST
Where
Westchester County, 2.17 mi ESE of Greenburgh to 2.14 mi WNW of Scarsdale
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
40.989, -73.811

The Bronx River Parkway was closed in Greenville due to flooding.

Flash Flood, Queens

When
August 22, 2:42 PM EST to 4:55 PM EST
Where
Queens County, 0.93 mi SE of Richmond Hill to 0.96 mi SE of Richmond Hill
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
40.691, -73.807

Tuskegee Airmen Way in Jamaica, Queens was closed due to flooding.

Flash Flood, Rockland

When
August 22, 3:08 PM EST to 4:45 PM EST
Where
Rockland County, 0.57 mi ENE of Germonds to 0.52 mi NE of Germonds
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
41.124, -74.041

North Main Street in Hillcrest was closed due to flooding.

Flash Flood, Queens

When
August 22, 4:00 PM EST to 4:55 PM EST
Where
Queens County, 1.05 mi NNW of Woodhaven to 1.12 mi NNW of Woodhaven
Cause
Heavy Rain
Reported by
Public
Coordinates
40.713, -73.861

A car was stalled in high water on Woodhaven Boulevard in Rego Park, Queens.

Flash Flood, Westchester

When
August 22, 4:01 PM EST to 4:45 PM EST
Where
Westchester County, 1.51 mi N of Tuckahoe to 1.57 mi N of Tuckahoe
Cause
Heavy Rain
Reported by
Broadcast Media
Coordinates
40.972, -73.830

Flooding was reported at the Crestwood Lake Apartments on Beaumont Circle in Yonkers.

Flash Flood, Rockland

When
August 22, 4:15 PM EST to 4:45 PM EST
Where
Rockland County, 0.47 mi E of Spring Vly Arpt to 0.3 mi NE of Hillcrest
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
41.121, -74.011

West Clarkstown Road in New City was closed due to flooding.

Flash Flood, Kings

When
August 22, 4:25 PM EST to 4:55 PM EST
Where
Kings County, 1.72 mi W of Brooklyn to 2.17 mi WNW of Brooklyn
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
40.654, -73.962

Parkside Avenue was flooded between Coney Island Avenue and Ocean Avenue in Flatbush, Brooklyn.

Flash Flood, Westchester

When
August 22, 4:29 PM EST to 4:45 PM EST
Where
Westchester County, 0.91 mi NW of Pelham Manor to 1.11 mi WNW of Pelham Manor
Cause
Heavy Rain
Reported by
Department of Highways
Coordinates
40.888, -73.814

All lanes were closed due to flooding on the northbound Hutchinson River Parkway between I-95 and Exit 13 (Mamaroneck Avenue) in Pelham.

Flash Flood, Rockland

When
August 22, 4:51 PM EST to 8:18 PM EST
Where
Rockland County, 0.27 mi S of Central Nyack to 0.33 mi S of Central Nyack
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
41.096, -73.950

The ramp from Route 303 to westbound Route 59 in Central Nyack was closed due to flooding with a car stranded.

Flash Flood, Westchester

When
August 22, 6:06 PM EST to 8:18 PM EST
Where
Westchester County, 0.62 mi SSW of Mt Vernon to 1.03 mi SSW of Mt Vernon
Cause
Heavy Rain
Reported by
Department of Highways
Coordinates
40.911, -73.852

All lanes were closed in both directions due to flooding on the Bronx River Parkway in Mount Vernon between Exit 10A (Yonkers Avenue) and Exit 10B (Bronx River Road).

Flood, Bronx

When
August 22, 6:45 PM EST to August 23, 6:15 AM EST
Where
Bronx County, 0.44 mi SSE of Fordham to 0.71 mi SE of Fordham
Cause
Heavy Rain
Reported by
River/Stream Gage
Coordinates
40.864, -73.876

The Bronx River at the Bronx Botanical Gardens rose above minor flood stage (3.0 feet) at 6:45pm EST on August 22. It then continued to rise, exceeding moderate flood stage (3.5 feet) at 8:45pm EST before cresting at a height of 3.83 feet at 11:30pm EST. The river fell below moderate flood stage at 3:45am EST on August 23, then below minor flood stage at 6:15am EST.

Flash Flood, Westchester

When
August 22, 7:48 PM EST to 8:18 PM EST
Where
Westchester County, 0.87 mi SE of East View to 0.89 mi SE of East View
Cause
Heavy Rain
Reported by
Department of Highways
Coordinates
41.072, -73.817

Route 9A was closed in both directions due to flooding in the vicinity of Saw Mill River Road in Ardsley.

What these are

Flash Flood
Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
Flood
Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in New York in 2021Every state in 2021This day in weather historyWarnings in New York, August 2021

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 981848, 981850, 981852, 981853, 981857, 981882, 981860, 981862, 981863, 981891, 981867, 981864, 981870, 981876, 981888, 981879, 982575, 981885.