Alert archive / New Jersey / Flash Flood Warnings in 2021

Flash Flood Warning 10, NWS New York, NY

July 8, 2021Rockland County, Westchester County, New York; Bergen County, Essex County, Passaic County, New Jersey; Greater Bridgeport Planning Region, Connecticut

NWS New York, NY issued this flash flood warning at Jul 8, 2021, 3:15 PM EDT for Rockland County, Westchester County, New York; Bergen County, Essex County, Passaic County, New Jersey; Greater Bridgeport Planning Region, Connecticut. It was in force for 3 hr. 5 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, 3:15 PM EDT (19:15 UTC)
Expired
Jul 8, 2021, 6:15 PM EDT
In force
3 hr
Issued by
NWS New York, NY
Area
Storm-based polygon
Flood severity
None

Counties Greater Bridgeport Planning Region, CT, Bergen County, NJ, Essex County, NJ, Passaic County, NJ, Rockland County, NY, Westchester County, NY

The radar

The Brookhaven radar (KOKX), 106 km from the middle of the area, began a volume at 19:15 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, 4:06 PM EDTFLASH FLOOD2 Ssw Greenville, NYCENTRAL PARK AVE IMPASSABLE DUE TO FLOODING. WATER UP TO CAR DOOR.
Jul 8, 4:21 PM EDTFLASH FLOOD1 Ene Ardsley, NYALL LANES BLOCKED BOTH DIRECTIONS ON SPRAIN BROOK PARKWAY.
Jul 8, 4:30 PM EDTFLASH FLOODHackensack, NJHEAVY FLOODING. CARS STUCK ON ROADS AND MULTIPLE RESCUES ARE ONGOING.
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, 5:15 PM EDTFLASH FLOOD1 Nnw Teterboro Airport, NJFLOODING ON NJ 17 NORTHBOUND NORTH OF US 46. ALL LANES CLOSED.

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, 7.3 hours before the alert went out and 106 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.

827 
WGUS51 KOKX 081915
FFWOKX
CTC001-NJC003-013-031-NYC087-119-082215-
/O.NEW.KOKX.FF.W.0010.210708T1915Z-210708T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Upton has issued a

* Flash Flood Warning for...
  Southern Fairfield County in southern Connecticut...
  Bergen County in northeastern New Jersey...
  Northeastern Essex County in northeastern New Jersey...
  Eastern Passaic County in northeastern New Jersey...
  Rockland County in southeastern New York...
  Southern Westchester County in southeastern New York...

* Until 615 PM EDT.

* At 315 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1.5 and 2.5 inches of 
  rain have fallen. The expected rainfall rate is 1.5 inches in 3 
  hours. Flash flooding is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

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

* Some locations that will experience flash flooding include...
  Yonkers, Paterson, Stamford, Passaic, White Plains, Wayne, 
  Bloomfield, Hackensack, Port Chester, Bergenfield, Paramus, 
  Ridgewood, Lyndhurst, Rutherford, Nanuet, Tarrytown, Dobbs Ferry, 
  Nyack, Tappan and Greenwich.

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 4097 7428 4113 7402 4118 7362 4107 7349
      4090 7387 4092 7392 4087 7394 4078 7414
      4079 7415 4077 7415 4076 7419 4091 7433
      4091 7430 4090 7428 4090 7427 4091 7427
      4092 7428 4093 7429 4094 7428

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1.5 INCHES IN 3 HOURS

$$

DJ
2 follow-up statements
524 
WGUS71 KOKX 082059
FFSOKX

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

CTC001-NJC003-013-031-NYC087-119-082215-
/O.CON.KOKX.FF.W.0010.000000T0000Z-210708T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Fairfield CT-Bergen NJ-Essex NJ-Passaic NJ-Rockland NY-Westchester
NY-
459 PM EDT Thu Jul 8 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 615 PM EDT THIS 
EVENING FOR SOUTHERN FAIRFIELD, BERGEN, NORTHEASTERN ESSEX, EASTERN 
PASSAIC, ROCKLAND AND SOUTHERN WESTCHESTER COUNTIES...

At 459 PM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 1.5 and 3 inches of rain have 
fallen. The expected rainfall rate is 1 to 1.5 inches in 3 hours. 
Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

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

Some locations that will experience flash flooding include...
  Yonkers, Paterson, Stamford, Passaic, White Plains, Wayne, 
  Bloomfield, Hackensack, Port Chester, Bergenfield, Paramus, 
  Ridgewood, Lyndhurst, Rutherford, Nanuet, Tarrytown, Dobbs Ferry, 
  Nyack, Tappan and Greenwich.

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 4097 7428 4113 7402 4118 7362 4107 7349
      4090 7387 4092 7392 4087 7394 4078 7414
      4079 7415 4077 7415 4076 7419 4091 7433
      4091 7430 4090 7428 4090 7427 4091 7427
      4092 7428 4093 7429 4094 7428

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-1.5 INCHES IN 3 HOURS

$$

DJ
114 
WGUS71 KOKX 082210
FFSOKX

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

CTC001-NJC003-013-031-NYC087-119-082220-
/O.EXP.KOKX.FF.W.0010.000000T0000Z-210708T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Fairfield CT-Bergen NJ-Essex NJ-Passaic NJ-Rockland NY-Westchester
NY-
610 PM EDT Thu Jul 8 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 615 PM EDT THIS EVENING FOR 
SOUTHERN FAIRFIELD, BERGEN, NORTHEASTERN ESSEX, EASTERN PASSAIC, 
ROCKLAND AND SOUTHERN WESTCHESTER COUNTIES...

Flash flooding is no longer expected to pose a threat. 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 4097 7428 4113 7402 4118 7362 4107 7349
      4090 7387 4092 7392 4087 7394 4078 7414
      4079 7415 4077 7415 4076 7419 4091 7433
      4091 7430 4090 7428 4090 7427 4091 7427
      4092 7428 4093 7429 4094 7428

$$

DJ

The office that day

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

IssuedProductOfficeCountiesLasted
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, 12:59 PM EDTSpecial Weather StatementOKXRockland46 min
Jul 8, 1:24 PM EDTSevere Thunderstorm WarningOKXRockland51 min
Jul 8, 2:11 PM EDTSevere Thunderstorm WarningOKXBronx, Rockland, Westchester49 min
Jul 8, 2:29 PM EDTAreal Flood AdvisoryOKXRockland, Westchester2 hr
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, 3:53 PM EDTFlash Flood WarningOKXBronx, Kings, Nassau, New York, Queens, Westchester3 hr
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, 5:06 PM EDTFlash Flood Warning Considerable damage threatOKXBronx, New York, Westchester3 hr
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, 6:15 PM EDTAreal Flood AdvisoryOKXRockland, Westchester3 hr
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
Jul 8, 3:08 PM EDTSpecial Weather StatementOKXBergen37 min
Jul 8, 3:27 PM EDTSpecial Weather StatementOKXEssex48 min
Jul 8, 6:35 PM EDTSpecial Weather StatementOKXBergen, Essex, Hudson, Union40 min
Jul 8, 7:25 PM EDTRiver Flood WarningOKXBergen12 hr
Jul 7, 8:25 PM EDTSevere Thunderstorm WarningOKXGreater Bridgeport Planning Region35 min
Jul 7, 9:06 PM EDTSpecial Weather StatementOKX39 min
Jul 7, 9:41 PM EDTSpecial Weather StatementOKX49 min
Jul 8, 12:49 AM EDTSpecial Weather StatementOKX41 min
Jul 8, 1:26 AM EDTSpecial Weather StatementOKX49 min
Jul 8, 1:30 AM EDTSpecial Weather StatementOKX45 min
Jul 8, 2:24 AM EDTSpecial Weather StatementOKX51 min
Jul 8, 2:00 PM EDTSevere Thunderstorm WarningOKXGreater Bridgeport Planning Region, Naugatuck Valley Planning Region45 min
Jul 8, 2:45 PM EDTSpecial Weather StatementOKX45 min
Jul 8, 4:06 PM EDTSpecial Weather StatementOKX39 min
Jul 8, 4:22 PM EDTAreal Flood AdvisoryOKXGreater Bridgeport Planning Region, Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region3 hr
Jul 8, 4:53 PM EDTSpecial Weather StatementOKX52 min

Nearby

Flash Flood Warnings in New Jersey, 2021Flash Flood Warnings in New York, 2021Flash Flood Warnings in Connecticut, 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.