Alert archive / Iowa / Flash Flood Warnings in 2004

Flash Flood Warning 28, NWS Sioux Falls, SD

August 23, 2004Cherokee County, Iowa

NWS Sioux Falls, SD issued this flash flood warning at Aug 23, 2004, 1:20 AM CDT for Cherokee County, Iowa. It was in force for 115 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 23, 2004, 1:20 AM CDT (06:20 UTC)
Expired
Aug 23, 2004, 3:15 AM CDT
In force
115 min
Issued by
NWS Sioux Falls, SD
Area
Counties, with a storm outline in the text

County Cherokee County, IA

The radar

The Sioux Falls radar (KFSD), 130 km from the middle of the area, began a volume at 06:19 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, 6.3 hours before the alert went out and 164 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, Omaha, NE at 00:00Z on 2004-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3453 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, Omaha, NE at 00:00Z on 2004-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 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
3453 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
1486 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
69 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.

000 
WGUS53 KFSD 230621
FFWFSD
IAC035-230815-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
120 AM CDT MON AUG 23 2004

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CHEROKEE COUNTY IN NORTHWEST IOWA

* UNTIL 315 AM CDT

* AT 120 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAINS...SOUTH OF A LINE FROM
  8 MILES SOUTH OF MARCUS TO AURELIA...MOVING NORTH AT 5 MPH.

AT 120 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THAT 2 TO 4 INCHES OF RAIN HAD FALLEN OVER SOUTHERN CHEROKEE COUNTY.

ADDITIONAL RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE POSSIBLE IN THE 
WARNED AREA.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND OTHER LOW
LYING AREAS ARE SUBJECT TO FLOODING.

LAT...LON 4258 9586 4258 9541 4290 9542 4290 9586

$$

CPJ
3 follow-up statements
000 
WGUS73 KFSD 230656
FFSFSD
IAC035-230815-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
156 AM CDT MON AUG 23 2004

...A FLASH FLOOD WARNING CONTINUES UNTIL 315 AM CDT FOR CHEROKEE
COUNTY...

AT 154 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE THUNDERSTORMS PRODUCING VERY HEAVY RAIN.  THESE STORMS WERE 
LOCATED SOUTH OF A LINE FROM MARCUS TO CHEROKEE...MOVING NORTH AT 5 
MPH.

ADDITIONAL RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE LIKELY IN THE 
WARNED AREA.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND OTHER LOW
LYING AREAS ARE SUBJECT TO FLOODING.

LAT...LON 4258 9586 4258 9541 4290 9542 4290 9583

$$

CPJ
000 
WGUS73 KFSD 230739
FFSFSD
IAC035-230815-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
238 AM CDT MON AUG 23 2004

...A FLASH FLOOD WARNING CONTINUES UNTIL 315 AM CDT FOR CHEROKEE
COUNTY...

AT 234 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE THUNDERSTORMS PRODUCING VERY HEAVY RAIN.  THESE STORMS WERE 
LOCATED SOUTHWEST OF A LINE EXTENDING FROM MARCUS TO NEAR 
AURELIA...MOVING NORTHEAST AT 5 MPH.

ADDITIONAL RAINFALL AMOUNTS AROUND 1 INCH ARE POSSIBLE IN THE WARNED 
AREA.

LAT...LON 4258 9586 4258 9541 4290 9542 4290 9586

$$

CPJ
000 
WGUS73 KFSD 230811
FFSFSD
IAC035-230825-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
310 AM CDT MON AUG 23 2004

...THE FLASH FLOOD WARNING FOR CHEROKEE COUNTY WILL EXPIRE AT 315 AM
CDT...

THUNDERSTORMS HAVE WEAKENED ACROSS THE COUNTY...AND THE THREAT OF 
FLASH FLOODING HAS DIMINISHED. THEREFORE THE WARNING WILL BE ALLOWED 
TO EXPIRE AT 315 AM CDT. 

LAT...LON 4258 9586 4258 9541 4290 9542 4290 9586

$$

CPJ

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 22, 10:38 PM CDTSevere Thunderstorm WarningFSDPlymouth52 min

Nearby

Flash Flood Warnings in Iowa, 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.