Alert archive / New York / Flash Flood Watches in 2021

Flash Flood Watch 7, NWS New York, NY

August 26, 20215 counties in New Jersey; 7 counties in New York

NWS New York, NY issued this flash flood watch at Aug 26, 2021, 3:35 PM EDT for 5 counties in New Jersey; 7 counties in New York. It took effect at Aug 27, 2021, 2:00 PM EDT. It was in force for 21 hr.

The area

The counties it named.

The facts

Issued
Aug 26, 2021, 3:35 PM EDT (19:35 UTC)
In effect from
Aug 27, 2021, 2:00 PM EDT
Expired
Aug 28, 2021, 11:00 AM EDT
In force
21 hr
Issued by
NWS New York, NY
Flood severity
None

Counties Bergen County, NJ, Essex County, NJ, Hudson County, NJ, Passaic County, NJ, Union County, NJ, Bronx County, NY, Kings County, NY, New York County, NY, Queens County, NY, Richmond County, NY, Rockland County, NY, Westchester County, NY

The radar

The Brookhaven radar (KOKX), 100 km from the middle of the area, began a volume at 19:38 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.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 7.6 hours before the alert went out and 100 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 2021-08-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 844 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 2021-08-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 square meters per square second.1939Sfc1 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
844 J/kg
Mixed-layer CIN
-55 J/kg
Mixed-layer LCL
1230 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
11 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

125 
WGUS61 KOKX 261935
FFAOKX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service New York NY
335 PM EDT Thu Aug 26 2021

NJZ002-004-006-103>108-270830-
/O.NEW.KOKX.FF.A.0007.210827T1800Z-210829T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Western Passaic-Eastern Passaic-Hudson-Western Bergen-Eastern Bergen-
Western Essex-Eastern Essex-Western Union-Eastern Union-
335 PM EDT Thu Aug 26 2021

...FLASH FLOOD WATCH IN EFFECT FROM FRIDAY AFTERNOON THROUGH LATE 
SATURDAY NIGHT...

The National Weather Service in Upton has issued a

* Flash Flood Watch for a portion of northeast New Jersey, including 
  the following areas, Eastern Bergen, Eastern Essex, Eastern 
  Passaic, Eastern Union, Hudson, Western Bergen, Western Essex, 
  Western Passaic and Western Union.

* From Friday afternoon through late Saturday night.

* A moist environment with slow moving convection may result in a 
  quick 1 to 2 inches of rain from Friday afternoon through Saturday 
  night. With recent heavy rainfall, it won't take much additional 
  rain to result in flash flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

MW
5 follow-up statements
647 
WGUS61 KOKX 270952
FFAOKX

Flood Watch
National Weather Service New York NY
552 AM EDT Fri Aug 27 2021

NJZ002-004-006-103>108-272100-
/O.CON.KOKX.FF.A.0007.210827T1800Z-210829T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Western Passaic-Eastern Passaic-Hudson-Western Bergen-Eastern Bergen-
Western Essex-Eastern Essex-Western Union-Eastern Union-
552 AM EDT Fri Aug 27 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 2 PM EDT THIS AFTERNOON 
THROUGH LATE SATURDAY NIGHT...

The Flash Flood Watch continues for

* A portion of northeast New Jersey, including the following areas, 
  Eastern Bergen, Eastern Essex, Eastern Passaic, Eastern Union, 
  Hudson, Western Bergen, Western Essex, Western Passaic and Western 
  Union.

* From 2 PM EDT this afternoon through late Saturday night.

* A moist environment with slow moving convection may result in a 
  quick 1 to 2 inches of rain from Friday afternoon through Saturday 
  night. With recent heavy rainfall, it will not take much 
  additional rain to result in flash flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

JP
592 
WGUS61 KOKX 271551
FFAOKX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service New York NY
1151 AM EDT Fri Aug 27 2021

NYZ069-071>075-176-178-280500-
/O.EXA.KOKX.FF.A.0007.210827T1800Z-210829T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Rockland-Southern Westchester-New York (Manhattan)-Bronx-
Richmond (Staten Island)-Kings (Brooklyn)-Northern Queens-
Southern Queens-
1151 AM EDT Fri Aug 27 2021

...FLASH FLOOD WATCH IN EFFECT THROUGH LATE SATURDAY NIGHT...

The National Weather Service in Upton has expanded the

* Flash Flood Watch to include a portion of southeast New York, 
  including the following areas, Bronx, Kings (Brooklyn), New 
  York (Manhattan), Northern Queens, Richmond (Staten Island), 
  Rockland, Southern Queens, and Southern Westchester. 

* Through late Saturday night

* A moist environment could result in heavy rain producing
  thunderstorms this afternoon into Saturday night. With recent
  heavy rainfall, it will not take much additional rain to result
  in flash flooding. The greatest risk looks to be this afternoon
  through Saturday afternoon.

* Rainfall rates of 1 to 2 inches per hour could result in flash
  flooding, especially in low-lying and poor drainage areas such 
  as highway underpasses.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$

NJZ002-004-006-103>108-280500-
/O.CON.KOKX.FF.A.0007.210827T1800Z-210829T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Western Passaic-Eastern Passaic-Hudson-Western Bergen-
Eastern Bergen-Western Essex-Eastern Essex-Western Union-
Eastern Union-
1151 AM EDT Fri Aug 27 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE SATURDAY
NIGHT...

The Flash Flood Watch continues for

* In northeast New Jersey: all areas of Bergen, Essex, Hudson, 
  Passaic and Union Counties. 

* Through late Saturday night

* A moist environment could result in heavy rain producing
  thunderstorms this afternoon into Saturday night. With recent
  heavy rainfall, it will not take much additional rain to result
  in flash flooding.

* Rainfall rates of 1 to 2 inches per hour could result in flash
  flooding, especially in low-lying and poor drainage areas such
  as highway underpasses as well as near creeks and rivers. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$

STACHELSKI
828 
WGUS61 KOKX 271928
FFAOKX

Flood Watch
National Weather Service New York NY
328 PM EDT Fri Aug 27 2021

NJZ002-004-006-103>108-NYZ069-071>075-176-178-280830-
/O.CON.KOKX.FF.A.0007.000000T0000Z-210829T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Western Passaic-Eastern Passaic-Hudson-Western Bergen-
Eastern Bergen-Western Essex-Eastern Essex-Western Union-
Eastern Union-Rockland-Southern Westchester-New York (Manhattan)-
Bronx-Richmond (Staten Island)-Kings (Brooklyn)-Northern Queens-
Southern Queens-
328 PM EDT Fri Aug 27 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE SATURDAY
NIGHT...

The Flash Flood Watch continues for

* Portions of northeast New Jersey and southeast New York, 
  including the following areas, in northeast New Jersey, 
  Eastern Bergen, Eastern Essex, Eastern Passaic, Eastern Union, 
  Hudson, Western Bergen, Western Essex, Western Passaic, and 
  Western Union. In southeast New York, Bronx, Kings (Brooklyn), 
  New York (Manhattan), Northern Queens, Richmond (Staten 
  Island), Rockland, Southern Queens, and Southern Westchester. 

* Through late Saturday night

* A moist environment could result in heavy rain producing 
  thunderstorms this afternoon into Saturday night. With recent 
  heavy rainfall, it will not take much additional rain to 
  result in flash flooding. The greatest risk looks to be this 
  afternoon through Saturday afternoon. 

* Rainfall rates of 1 to 2 inches per hour could result in flash
  flooding, especially in low-lying and poor drainage areas such
  as highway underpasses. Areas along creeks and rivers are also
  vulnerable especially in northeast New Jersey and Rockland
  County, New York.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

&&

$$

STACHELSKI
081 
WGUS61 KOKX 280811
FFAOKX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service New York NY
411 AM EDT Sat Aug 28 2021

NJZ002-004-006-103>108-281500-
/O.EXT.KOKX.FF.A.0007.000000T0000Z-210828T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Western Passaic-Eastern Passaic-Hudson-Western Bergen-Eastern Bergen-
Western Essex-Eastern Essex-Western Union-Eastern Union-
411 AM EDT Sat Aug 28 2021

...FLASH FLOOD WATCH NOW IN EFFECT UNTIL 11 AM EDT THIS MORNING...

The Flash Flood Watch is now in effect for

* A portion of northeast New Jersey, including the following areas, 
  Eastern Bergen, Eastern Essex, Eastern Passaic, Eastern Union, 
  Hudson, Western Bergen, Western Essex, Western Passaic and Western 
  Union.

* Until 11 AM EDT this morning.

* A moist environment with slow moving convection may result in a 
  quick 1 to 2 inches of rain through Saturday morning. With recent 
  heavy rainfall, it will not take much additional rain to result in 
  flash flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

NYZ069-071>075-176-178-281500-
/O.EXT.KOKX.FF.A.0007.000000T0000Z-210828T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Rockland-Southern Westchester-New York (Manhattan)-Bronx-Richmond
(Staten Island)-Kings (Brooklyn)-Northern Queens-Southern Queens-
411 AM EDT Sat Aug 28 2021

...FLASH FLOOD WATCH NOW IN EFFECT UNTIL 11 AM EDT THIS MORNING...

The Flash Flood Watch is now in effect for

* A portion of southeast New York, including the following areas, 
  Bronx, Kings (Brooklyn), New York (Manhattan), Northern Queens, 
  Richmond (Staten Island), Rockland, Southern Queens and Southern 
  Westchester.

* Until 11 AM EDT this morning.

* A moist environment with slow moving convection may result in a 
  quick 1 to 2 inches of rain through Saturday morning. With recent 
  heavy rainfall, it will not take much additional rain to result in 
  flash flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

JE
633 
WGUS61 KOKX 281456
FFAOKX

Flood Watch
National Weather Service New York NY
1056 AM EDT Sat Aug 28 2021

NJZ002-004-006-103>108-NYZ069-071>075-176-178-281600-
/O.EXP.KOKX.FF.A.0007.000000T0000Z-210828T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Western Passaic-Eastern Passaic-Hudson-Western Bergen-Eastern Bergen-
Western Essex-Eastern Essex-Western Union-Eastern Union-Rockland-
Southern Westchester-New York (Manhattan)-Bronx-Richmond (Staten
Island)-Kings (Brooklyn)-Northern Queens-Southern Queens-
1056 AM EDT Sat Aug 28 2021

...FLASH FLOOD WATCH WILL BE ALLOWED TO EXPIRE AT 11 AM EDT THIS 
MORNING...

The Flash Flood Watch for portions of northeast New Jersey and 
southeast New York, including the following areas, in northeast New 
Jersey, Eastern Bergen, Eastern Essex, Eastern Passaic, Eastern 
Union, Hudson, Western Bergen, Western Essex, Western Passaic and 
Western Union. In southeast New York, Bronx, Kings (Brooklyn), New 
York (Manhattan), Northern Queens, Richmond (Staten Island), 
Rockland, Southern Queens and Southern Westchester will be allowed 
to expire at 11 AM EDT this morning.

The Flood Watch is cancelled. Flooding is no longer expected to pose 
a threat. Please continue to heed remaining road closures.

$$

Fig

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 26, 5:33 PM EDTSpecial Weather StatementOKXBergen42 min
Aug 26, 5:52 PM EDTAreal Flood AdvisoryOKXBergen53 min

Nearby

Flash Flood Watches in New York, 2021Flash Flood Watches in New Jersey, 2021Every flash flood watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.