Alert archive / Nebraska / Flash Flood Warnings in 2002

Flash Flood Warning 9, NWS Omaha, NE

August 23, 2002Cass County, Nebraska

NWS Omaha, NE issued this flash flood warning at Aug 23, 2002, 3:28 AM CDT for Cass County, Nebraska. It was in force for 4 hr. 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 23, 2002, 3:28 AM CDT (08:28 UTC)
Expired: Aug 23, 2002, 7:30 AM CDT
In force: 4 hr
Issued by: NWS Omaha, NE
Area: Counties, with a storm outline in the text

County Cass County, NE

The radar

The Omaha radar (KOAX), 48 km from the middle of the area, began a volume at 08:29 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

Omaha, NE (KOAX), launched 00:00Z, 8.5 hours before the alert went out and 48 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: 3464 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 856 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 196 m²/s²
Significant tornado parameter: 2.0
Supercell composite: 11.3

Open this sounding in Storm Lab

The text

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

000 
WGUS53 KOAX 230828
FFWOMA
NEC025-231230-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE OMAHA NE
326 AM CDT FRI AUG 23 2002

THE NATIONAL WEATHER SERVICE IN OMAHA HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CASS COUNTY IN SOUTHEAST NEBRASKA

* UNTIL 730 AM CDT

* AT 326 AM CDT...RADAR STILL INDICATED SOME SCATTERED THUNDERSTORMS
  OVER PARTS OF CASS COUNTY.  AS OF 300 AM CDT LAW ENFORCEMENT  
  REPORTED CEDAR CREEK OUT OF ITS BANKS IN THE LOUISVILLE AREA.
  WATER WAS REPORTED OVER HIGHWAY 50.  THIS IS AN EXTENSION OF THE
  PREVIOUS WARNING.  

* SOME LOCATIONS AFFECTED...
  CEDAR CREEK
  WEEPING WATER CREEK
  CALAHAN CREEK
  EIGHT MILE CREEK

EXCESSIVE RUNOFF WILL CONTINUE TO CAUSE FLASH FLOODING OF SMALL 
CREEKS AND STREAMS.  IN ADDITION...COUNTRY ROADS AND FARMLANDS ALONG 
THE BANKS OF CREEKS AND STREAMS AND OTHER LOW LYING AREAS WILL BE
SUBJECT TO FLASH FLOODING.

LAT...LON 4105 9588 4080 9586 4079 9645 4101 9646

MILLER

The office that day

Everything else NWS Omaha, NE issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 22, 7:08 PM CDT	Severe Thunderstorm Warning	OAX	Cass	37 min
Aug 22, 7:15 PM CDT	Severe Thunderstorm Warning	OAX	Boone, Madison	45 min
Aug 22, 7:19 PM CDT	Severe Thunderstorm Warning	OAX	Otoe	26 min
Aug 22, 7:48 PM CDT	Severe Thunderstorm Warning	OAX	Cass, Otoe	27 min
Aug 22, 8:03 PM CDT	Severe Thunderstorm Warning	OAX	Madison	27 min
Aug 22, 8:23 PM CDT	Severe Thunderstorm Warning	OAX	Otoe	52 min
Aug 22, 8:42 PM CDT	Severe Thunderstorm Warning	OAX	Washington	33 min
Aug 22, 9:09 PM CDT	Tornado Warning	OAX	Saunders	36 min
Aug 22, 9:21 PM CDT	Tornado Warning	OAX	Douglas	24 min
Aug 22, 9:31 PM CDT	Severe Thunderstorm Warning	OAX	Saunders	29 min
Aug 22, 9:47 PM CDT	Severe Thunderstorm Warning	OAX	Douglas	43 min
Aug 22, 10:01 PM CDT	Severe Thunderstorm Warning	OAX	Sarpy, Saunders	29 min
Aug 22, 11:21 PM CDT	Severe Thunderstorm Warning	OAX	Cass	54 min
Aug 22, 11:37 PM CDT	Flash Flood Warning	OAX	Cass	4 hr
Aug 23, 1:23 AM CDT	Flash Flood Warning	OAX	Sarpy	6 hr
Aug 23, 1:59 AM CDT	Flash Flood Warning	OAX	Lancaster, Saunders	6 hr
Aug 23, 2:47 AM CDT	Flash Flood Warning	OAX	Otoe	6 hr
Aug 23, 3:58 AM CDT	Flash Flood Warning	OAX	Saline	6 hr
Aug 23, 4:31 AM CDT	Severe Thunderstorm Warning	OAX	Jefferson, Saline	29 min

Nearby

Flash Flood Warnings in Nebraska, 2002 Every flash flood warning in 2002

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.