Alert archive / New York / Flash Flood Warnings in 2011

Flash Flood Warning 33, NWS New York, NY

August 21, 2011Orange County, Rockland County, New York; Bergen County, Passaic County, New Jersey

NWS New York, NY issued this flash flood warning at Aug 21, 2011, 6:46 PM EDT for Orange County, Rockland County, New York; Bergen County, Passaic County, New Jersey. It was in force for 56 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 21, 2011, 6:46 PM EDT (22:46 UTC)
Expired: Aug 21, 2011, 7:42 PM EDT
In force: 56 min
Issued by: NWS New York, NY
Area: Storm-based polygon
Flood severity: None

Counties Bergen County, NJ, Passaic County, NJ, Orange County, NY, Rockland County, NY

The radar

The Brookhaven radar (KOKX), 117 km from the middle of the area, began a volume at 22:47 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, 10.8 hours before the alert went out and 117 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 874 J/kg
Mixed-layer CIN: -29 J/kg
Mixed-layer LCL: 857 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 55 m²/s²
0-3 km storm-relative helicity: 116 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

663 
WGUS51 KOKX 212246
FFWOKX
NJC003-031-NYC071-087-220045-
/O.NEW.KOKX.FF.W.0033.110821T2246Z-110822T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW YORK NY
646 PM EDT SUN AUG 21 2011

THE NATIONAL WEATHER SERVICE IN UPTON NY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  PASSAIC COUNTY IN NORTHEAST NEW JERSEY...
  ROCKLAND COUNTY IN SOUTHEAST NEW YORK...
  SOUTHEASTERN ORANGE COUNTY IN SOUTHEAST NEW YORK...
  NORTHWESTERN BERGEN COUNTY IN NORTHEAST NEW JERSEY...

* UNTIL 845 PM EDT...

* AT 643 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
HEAVY RAINFALL FROM THUNDERSTORMS FALLING OVER PASSAIC COUNTY WITH 
ADDITIONAL THUNDERSTORMS APPROACHING FROM THE SOUTHWEST. A TRAINED 
WEATHER SPOTTER REPORTED RAINFALL RATES OF AROUND 3 INCHES PER HOUR 
IN WEST MILFORD AND IS LIKELY CAUSING FLASH FLOODING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

&&

LAT...LON 4119 7438 4122 7442 4148 7400 4138 7396
      4133 7398 4129 7395 4124 7397 4116 7390
      4111 7390 4103 7408 4091 7428 4097 7428
      4098 7430 4101 7443 4104 7444 4102 7449
      4108 7451

$$

1 follow-up statement

306 
WGUS71 KOKX 212342
FFSOKX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NEW YORK NY
742 PM EDT SUN AUG 21 2011

NJC003-031-NYC071-087-212349-
/O.CAN.KOKX.FF.W.0033.000000T0000Z-110822T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BERGEN NJ-ORANGE NY-ROCKLAND NY-PASSAIC NJ-
742 PM EDT SUN AUG 21 2011

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR PASSAIC...
ROCKLAND...SOUTHEASTERN ORANGE AND NORTHWESTERN BERGEN COUNTIES...

HEAVY RAIN HAS MOVED OUT OF THE AREA AND THE FLASH FLOOD THREAT HAS 
ENDED...THEREFORE THE FLASH FLOOD WARNING HAS BEEN CANCELLED. 


A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT SUNDAY
EVENING FOR SOUTHERN CONNECTICUT AND NORTHEAST NEW JERSEY AND
SOUTHEAST NEW YORK.

LAT...LON 4119 7438 4122 7442 4148 7400 4138 7396
      4133 7398 4129 7395 4124 7397 4116 7390
      4111 7390 4103 7408 4091 7428 4097 7428
      4098 7430 4101 7443 4104 7444 4102 7449
      4108 7451

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 21, 3:49 AM EDT	Small Craft Advisory	OKX		30 hr
Aug 21, 6:00 AM EDT	Flash Flood Watch	OKX	Bronx, Kings, Nassau, New York, Orange, Putnam and 4 more	15 hr
Aug 21, 11:32 AM EDT	Special Weather Statement	OKX	Bronx, New York	43 min
Aug 21, 12:13 PM EDT	Special Weather Statement	OKX	Bronx	47 min
Aug 21, 12:26 PM EDT	Severe Thunderstorm Warning	OKX	Westchester	49 min
Aug 21, 12:51 PM EDT	Special Weather Statement	OKX	Orange	54 min
Aug 21, 12:59 PM EDT	Severe Thunderstorm Warning	OKX	Putnam	23 min
Aug 21, 1:09 PM EDT	Severe Thunderstorm Warning	OKX	Westchester	21 min
Aug 21, 1:17 PM EDT	Special Weather Statement	OKX	Rockland	58 min
Aug 21, 1:23 PM EDT	Special Weather Statement	OKX	Putnam	67 min
Aug 21, 1:28 PM EDT	Special Weather Statement	OKX	Orange	62 min
Aug 21, 1:43 PM EDT	Severe Thunderstorm Warning	OKX	Putnam, Rockland, Westchester	47 min
Aug 21, 2:15 PM EDT	Severe Thunderstorm Warning	OKX	Putnam	21 min
Aug 21, 3:43 PM EDT	Special Marine Warning	OKX		32 min
Aug 21, 4:00 PM EDT	Severe Thunderstorm Warning	OKX	Putnam, Westchester	45 min
Aug 21, 4:07 PM EDT	Severe Thunderstorm Warning	OKX	Kings, Nassau, Queens	38 min
Aug 21, 4:20 PM EDT	Special Marine Warning	OKX		40 min
Aug 21, 4:37 PM EDT	Tornado Warning	OKX	Putnam, Westchester	38 min
Aug 21, 4:47 PM EDT	Severe Thunderstorm Warning	OKX	Nassau, Queens, Suffolk	17 min
Aug 21, 4:58 PM EDT	Tornado Warning	OKX	Putnam	30 min
Aug 21, 5:51 PM EDT	Special Weather Statement	OKX	Rockland, Westchester	39 min
Aug 21, 6:33 PM EDT	Areal Flood Advisory	OKX	Orange, Rockland	117 min
Aug 21, 6:38 PM EDT	Special Weather Statement	OKX	Rockland	52 min
Aug 21, 7:19 PM EDT	Special Weather Statement	OKX	Putnam	41 min
Aug 21, 7:25 PM EDT	Areal Flood Advisory	OKX	Putnam, Westchester	2 hr
Aug 21, 12:38 PM EDT	Severe Thunderstorm Warning	OKX	Bergen, Essex, Passaic	50 min

Nearby

Flash Flood Warnings in New York, 2011 Flash Flood Warnings in New Jersey, 2011 Every flash flood warning in 2011

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.