Alert archive / New York / Flash Flood Warnings in 2004

Flash Flood Warning 21, NWS New York, NY

August 21, 2004Orange County, New York

NWS New York, NY issued this flash flood warning at Aug 21, 2004, 11:48 AM EDT for Orange County, New York. It was in force for 117 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 21, 2004, 11:48 AM EDT (15:48 UTC)
Expired
Aug 21, 2004, 1:45 PM EDT
In force
117 min
Issued by
NWS New York, NY
Area
Whole counties

County Orange County, NY

The radar

The Albany radar (KENX), 133 km from the middle of the area, began a volume at 15:47 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, 3.8 hours before the alert went out and 135 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 2004-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1043 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2004-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 156 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
1043 J/kg
Mixed-layer CIN
-43 J/kg
Mixed-layer LCL
802 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
156 m²/s²
0-3 km storm-relative helicity
180 m²/s²
Significant tornado parameter
0.7
Supercell composite
5.6

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KOKX 211550
FFWOKX
NYC071-211745-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE UPTON NY
1148 AM EDT SAT AUG 21 2004

THE NATIONAL WEATHER SERVICE IN UPTON NY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  ORANGE COUNTY IN SOUTHEAST NEW YORK

* UNTIL 145 PM EDT

* AT 1148 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR            
  INDICATED AN AREA OF THUNDERSTORMS WITH VERY HEAVY RAIN 
  OVER MUCH OF ORANGE COUNTY...MOVING NORTHEAST AT 40 MPH. 

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. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.
MOVE TO HIGHER GROUND.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT. MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. DO NOT
ATTEMPT TO CROSS BRIDGES...DIPS...OR OTHER LOW SPOTS IF WATER COVERS
THE ROADWAY. NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL
ONE...ON FOOT. TO ESCAPE RISING WATER MOVE UP TO HIGHER GROUND.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE. IF YOUR VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.

$$

TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT AGENCY
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN
UPTON NY.

LAT...LON 4136 7467 4115 7426 4136 7399 4157 7401
      4161 7431

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 8:01 PM EDTSevere Thunderstorm WarningOKXOrange44 min
Aug 20, 8:04 PM EDTSevere Thunderstorm WarningOKXWestchester26 min
Aug 20, 8:19 PM EDTSevere Thunderstorm WarningOKXPutnam41 min
Aug 21, 1:36 PM EDTSevere Thunderstorm WarningOKXRockland24 min
Aug 21, 2:22 PM EDTSpecial Marine WarningOKX53 min
Aug 21, 2:24 PM EDTSevere Thunderstorm WarningOKXRichmond21 min
Aug 21, 2:27 PM EDTSpecial Marine WarningOKX33 min
Aug 21, 2:31 PM EDTSevere Thunderstorm WarningOKXKings, Nassau, Queens44 min
Aug 21, 2:47 PM EDTSpecial Marine WarningOKX58 min
Aug 21, 3:14 PM EDTFlash Flood WarningOKXNassau, Queens, Suffolk2 hr
Aug 21, 3:16 PM EDTSevere Thunderstorm WarningOKXNassau, Suffolk44 min
Aug 21, 3:19 PM EDTSpecial Marine WarningOKX41 min
Aug 21, 3:27 PM EDTSpecial Marine WarningOKX63 min
Aug 21, 4:15 PM EDTSpecial Marine WarningOKX45 min

Nearby

Flash Flood Warnings in New York, 2004Every flash flood warning in 2004

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.