Alert archive / New York / Flash Flood Warnings in 2021

Flash Flood Warning 12, NWS New York, NY

July 8, 2021Bergen County, New Jersey; Bronx County, New York County, Westchester County, New York

NWS New York, NY issued this flash flood warning at Jul 8, 2021, 5:06 PM EDT for Bergen County, New Jersey; Bronx County, New York County, Westchester County, New York. It was in force for 3 hr. 2 reports 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
Jul 8, 2021, 5:06 PM EDT (21:06 UTC)
Expired
Jul 8, 2021, 8:15 PM EDT
In force
3 hr
Issued by
NWS New York, NY
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

Counties Bergen County, NJ, Bronx County, NY, New York County, NY, Westchester County, NY

The radar

The Brookhaven radar (KOKX), 84 km from the middle of the area, began a volume at 21:07 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
Jul 8, 5:13 PM EDTFLASH FLOOD2 Ne Riverdale, NYROAD CLOSED ON SAW MILL RIVER PARKWAY SOUTHBOUND AT MCLEAN AVE DUE TO FLOODING.
Jul 8, 5:55 PM EDTFLASH FLOOD1 Ssw Washington Height, NYHARLEM RIVER DRIVE SOUTHBOUND IN AREA OF EXIT 23 CLOSED DUE TO FLOODING.

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

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.1 hours before the alert went out and 84 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 2021-07-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 973 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2021-07-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 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
973 J/kg
Mixed-layer CIN
-77 J/kg
Mixed-layer LCL
751 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.3

Open this sounding in Storm Lab

The text

As transmitted.

754 
WGUS51 KOKX 082106
FFWOKX
NJC003-NYC005-061-119-090015-
/O.NEW.KOKX.FF.W.0012.210708T2106Z-210709T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New York NY
506 PM EDT Thu Jul 8 2021

The National Weather Service in Upton has issued a

* Flash Flood Warning for...
  Southeastern Bergen County in northeastern New Jersey...
  Bronx County in southeastern New York...
  New York (Manhattan) County in southeastern New York...
  Southern Westchester County in southeastern New York...

* Until 815 PM EDT.

* At 506 PM EDT, the public reported thunderstorms producing heavy 
  rain across the warned area. Between 2 and 4 inches of rain have 
  fallen. The expected rainfall rate is 1 to 2 inches in 1 hour. 
  Additional rainfall amounts of 1 to 2 inches are possible in the 
  warned area. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Public reported.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Yonkers, New Rochelle, Mott Haven, East Tremont, Ridgefield, 
  Throgs Neck Bridge, Harlem, Riverdale, Co-op City, Fort Lee, 
  Englewood, Bronxville, City Island, Upper West Side, Mount Vernon, 
  Eastchester, Cliffside Park, Palisades Park, Mamaroneck and 
  Tenafly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

Excessive runoff from heavy rainfall will cause flooding of urban 
areas, highways, streets and underpasses as well as other drainage 
areas and low lying spots.

&&

LAT...LON 4082 7402 4090 7398 4098 7391 4096 7369
      4092 7372 4090 7374 4088 7374 4084 7375
      4082 7379 4080 7377 4081 7382 4080 7386
      4079 7388 4080 7391 4079 7391 4077 7394
      4078 7400 4080 7398

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

DJ
2 follow-up statements
271 
WGUS71 KOKX 082315
FFSOKX

Flash Flood Statement
National Weather Service New York NY
715 PM EDT Thu Jul 8 2021

NJC003-NYC005-061-119-090015-
/O.CON.KOKX.FF.W.0012.000000T0000Z-210709T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bergen NJ-Bronx NY-New York (Manhattan) NY-Westchester NY-
715 PM EDT Thu Jul 8 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 PM EDT THIS 
EVENING FOR SOUTHEASTERN BERGEN, BRONX, NEW YORK (MANHATTAN) AND 
SOUTHERN WESTCHESTER COUNTIES...

At 715 PM EDT, local law enforcement reported numerous road closures 
and water rescues across the warned area. Between 2 and 4 inches of 
rain have fallen. A few additional showers are possible through this 
evening. Additional flash flooding is not expected.

HAZARD...Flooded and impassable roadways and swollen creeks and
         streams.

SOURCE...Law enforcement reported.

IMPACT...Flooded small creeks and streams, urban areas, highways,
         streets and underpasses as well as other poor drainage
         and low-lying areas.

Some locations that have experienced flash flooding include...
  Yonkers, New Rochelle, Mott Haven, East Tremont, Ridgefield, 
  Throgs Neck Bridge, Harlem, Riverdale, Co-op City, Fort Lee, 
  Englewood, Bronxville, City Island, Upper West Side, Mount Vernon, 
  Eastchester, Cliffside Park, Palisades Park, Mamaroneck and 
  Tenafly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.


&&

LAT...LON 4082 7402 4090 7398 4098 7391 4096 7369
      4092 7372 4090 7374 4088 7374 4084 7375
      4082 7379 4080 7377 4081 7382 4080 7386
      4079 7388 4080 7391 4079 7391 4077 7394
      4078 7400 4080 7398

FLASH FLOOD...OBSERVED

$$

DJ
656 
WGUS71 KOKX 090014
FFSOKX

Flash Flood Statement
National Weather Service New York NY
814 PM EDT Thu Jul 8 2021

NJC003-NYC005-061-119-090024-
/O.EXP.KOKX.FF.W.0012.000000T0000Z-210709T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bergen NJ-Bronx NY-New York (Manhattan) NY-Westchester NY-
814 PM EDT Thu Jul 8 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 815 PM EDT THIS EVENING FOR 
SOUTHEASTERN BERGEN, BRONX, NEW YORK (MANHATTAN) AND SOUTHERN 
WESTCHESTER COUNTIES...

Flash flooding is no longer expected to pose a threat. Additional 
rainfall may be possible. Please continue to heed remaining road 
closures.

A Flash Flood Watch remains in effect until 1200 PM EDT Friday for 
portions of southern Connecticut, northeast New Jersey and southeast 
New York.

LAT...LON 4082 7402 4090 7398 4098 7391 4096 7369
      4092 7372 4090 7374 4088 7374 4084 7375
      4082 7379 4080 7377 4081 7382 4080 7386
      4079 7388 4080 7391 4079 7391 4077 7394
      4078 7400 4080 7398

$$

DJ

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 8, 12:59 PM EDTSpecial Weather StatementOKXPassaic46 min
Jul 8, 1:24 PM EDTSevere Thunderstorm WarningOKXBergen, Passaic51 min
Jul 8, 2:11 PM EDTSevere Thunderstorm WarningOKXBergen, Passaic49 min
Jul 8, 2:29 PM EDTAreal Flood AdvisoryOKXBergen, Passaic2 hr
Jul 8, 3:08 PM EDTSpecial Weather StatementOKXBergen37 min
Jul 8, 3:15 PM EDTFlash Flood WarningOKXBergen, Essex, Passaic3 hr
Jul 8, 3:27 PM EDTSpecial Weather StatementOKXEssex48 min
Jul 8, 3:53 PM EDTFlash Flood WarningOKXBergen, Essex, Hudson3 hr
Jul 8, 6:15 PM EDTAreal Flood AdvisoryOKXBergen, Essex, Passaic3 hr
Jul 8, 6:35 PM EDTSpecial Weather StatementOKXBergen, Essex, Hudson, Union40 min
Jul 8, 7:25 PM EDTRiver Flood WarningOKXBergen12 hr
Jul 7, 8:02 PM EDTSpecial Weather StatementOKXPutnam43 min
Jul 7, 10:43 PM EDTSpecial Weather StatementOKXDutchess47 min
Jul 7, 11:19 PM EDTSpecial Weather StatementOKXOrange56 min
Jul 7, 11:34 PM EDTSpecial Weather StatementOKXOrange, Putnam56 min
Jul 7, 11:46 PM EDTSpecial Weather StatementOKXOrange, Putnam, Rockland, Westchester44 min
Jul 8, 12:18 AM EDTAreal Flood AdvisoryOKXOrange66 min
Jul 8, 12:29 AM EDTSpecial Weather StatementOKXPutnam, Westchester46 min
Jul 8, 12:44 AM EDTAreal Flood AdvisoryOKXOrange, Putnam62 min
Jul 8, 5:08 AM EDTTropical Storm WarningOKXNassau, Suffolk33 hr
Jul 8, 9:23 AM EDTAreal Flood AdvisoryOKXOrange112 min
Jul 8, 11:54 AM EDTSpecial Weather StatementOKXOrange66 min
Jul 8, 12:59 PM EDTSpecial Weather StatementOKXPutnam46 min
Jul 8, 2:53 PM EDTSpecial Marine WarningOKX52 min
Jul 8, 2:58 PM EDTSpecial Weather StatementOKXNassau, Queens47 min
Jul 8, 3:10 PM EDTSmall Craft AdvisoryOKX23 hr
Jul 8, 3:19 PM EDTSpecial Weather StatementOKXNew York41 min
Jul 8, 3:49 PM EDTSpecial Marine WarningOKX56 min
Jul 8, 4:00 PM EDTSpecial Weather StatementOKXNassau45 min
Jul 8, 4:37 PM EDTSpecial Weather StatementOKXBronx, New York38 min
Jul 8, 4:51 PM EDTSpecial Marine WarningOKX24 min
Jul 8, 5:03 PM EDTSpecial Weather StatementOKXNassau42 min
Jul 8, 5:16 PM EDTSevere Thunderstorm WarningOKXNassau, Suffolk44 min
Jul 8, 5:38 PM EDTAreal Flood AdvisoryOKXNassau, Suffolk3 hr
Jul 8, 5:59 PM EDTSpecial Weather StatementOKXSuffolk46 min
Jul 8, 6:40 PM EDTSpecial Weather StatementOKXSuffolk50 min
Jul 8, 6:59 PM EDTAreal Flood AdvisoryOKXKings, Nassau, New York, Queens90 min
Jul 8, 7:17 PM EDTSpecial Weather StatementOKXNassau43 min

Nearby

Flash Flood Warnings in New York, 2021Flash Flood Warnings in New Jersey, 2021Every flash flood warning in 2021

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.