Alert archive / Iowa / Flash Flood Warnings in 2011

Flash Flood Warning 19, NWS Sioux Falls, SD

June 26, 2011Cherokee County, Iowa

NWS Sioux Falls, SD issued this flash flood warning at Jun 26, 2011, 8:52 PM CDT for Cherokee County, Iowa. It was in force for 2 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 26, 2011, 8:52 PM CDT (01:52 UTC)
Expired
Jun 26, 2011, 11:07 PM CDT
In force
2 hr
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

County Cherokee County, IA

The radar

The Sioux Falls radar (KFSD), 131 km from the middle of the area, began a volume at 01:55 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.

What was reported inside it

TimeReportWhereRemark
Jun 26, 8:55 PM CDTFLASH FLOODCherokee, IASIGNIFICANT STREET FLOODING.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 1.9 hours before the alert went out and 169 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 2011-06-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2873 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, Omaha, NE at 00:00Z on 2011-06-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 248 square meters per square second.19395878Sfc1 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
2873 J/kg
Mixed-layer CIN
-31 J/kg
Mixed-layer LCL
501 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
248 m²/s²
0-3 km storm-relative helicity
308 m²/s²
Significant tornado parameter
6.2
Supercell composite
26.5

Open this sounding in Storm Lab

The text

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

093 
WGUS53 KFSD 270152
FFWFSD
IAC035-270500-
/O.NEW.KFSD.FF.W.0019.110627T0152Z-110627T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
852 PM CDT SUN JUN 26 2011

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

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

* UNTIL MIDNIGHT CDT

* AT 846 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. 
  RAINFALL ESTIMATES OF AROUND AN INCH HAS ALREADY FALLEN ACROSS THE 
  AREA WITH AN ADDITIONAL 1 TO 2 INCHES EXPECTED THROUGH 10 PM CDT.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  AURELIA...CHEROKEE...LARRABEE...QUIMBY AND WASHTA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

&&

LAT...LON 4256 9585 4279 9586 4280 9564 4291 9562
      4291 9539 4277 9538 4256 9539

$$
SCHUMACHER
2 follow-up statements
442 
WGUS73 KFSD 270208
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
908 PM CDT SUN JUN 26 2011

IAC035-270500-
/O.CON.KFSD.FF.W.0019.000000T0000Z-110627T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CHEROKEE IA-
908 PM CDT SUN JUN 26 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR CHEROKEE COUNTY UNTIL
MIDNIGHT CDT...

AT 900 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. 
DOPPLER RADAR ESTIMATED 1 TO 2 INCHES OF RAIN HAD FALLEN ACROSS THE 
AREA. ADDITIONAL RAINFALL OF UP TO 2 INCHES CAN BE 
EXPECTED...ESPECIALLY ALONG AND EAST OF HIGHWAY 59.

AT 850 PM CDT...A TRAINED WEATHER SPOTTER REPORTED STREET FLOODING 
IN CHEROKEE.  ALSO...THE AIRPORT AT CHEROKEE HAS REPORTED 1.17 OF 
RAIN...MOST OF THAT RAIN HAS OCCURRED SINCE 830 PM CDT.

SLOW MOVING THUNDERSTORMS ARE PRODUCING VERY HEAVY RAINFALL IN THE
WARNED AREA. RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH
FLOODING TO OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING
INCLUDE...AURELIA...CHEROKEE...LARRABEE...QUIMBY AND WASHTA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.


LAT...LON 4256 9585 4279 9586 4280 9564 4291 9562
      4291 9539 4277 9538 4256 9539

$$

SCHUMACHER
211 
WGUS73 KFSD 270407
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1107 PM CDT SUN JUN 26 2011

IAC035-270419-
/O.CAN.KFSD.FF.W.0019.000000T0000Z-110627T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CHEROKEE IA-
1107 PM CDT SUN JUN 26 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR CHEROKEE COUNTY IS
CANCELLED...

...A FLOOD WARNING REMAINS IN EFFECT UNTIL 11 AM CDT MONDAY... 

HEAVY RAIN HAS ENDED OVER THE WARNED AREA. STREAMS AND CREEKS IN THE 
WARNED AREA WERE SLOWLY BEGINNING TO RECEDE. HOWEVER...EXCESSIVE 
RUNOFF FROM HEAVY RAINFALL EARLY TONIGHT WILL CONTINUE TO CAUSE 
FLOODING...ESPECIALLY IN RURAL AREAS. IF FLOODING HAS BEEN 
OBSERVED...PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

IF FLOODING WAS OBSERVED PLEASE RELAY YOUR REPORT TO LOCAL LAW
ENFORCEMENT OR TO THE NATIONAL WEATHER SERVICE IN SIOUX FALLS.

LAT...LON 4256 9585 4279 9586 4280 9564 4291 9562
      4291 9539 4277 9538 4256 9539

$$

SCHUMACHER

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 26, 7:27 PM CDTFlash Flood WarningFSDWoodbury3 hr
Jun 26, 7:29 PM CDTSevere Thunderstorm WarningFSDWoodbury31 min
Jun 26, 7:37 PM CDTSevere Thunderstorm WarningFSDIda, Woodbury38 min
Jun 26, 7:56 PM CDTFlash Flood WarningFSDCherokee, O'Brien, Plymouth, Sioux3 hr
Jun 26, 7:59 PM CDTSevere Thunderstorm WarningFSDWoodbury31 min
Jun 26, 8:14 PM CDTSevere Thunderstorm WarningFSDIda, Woodbury31 min
Jun 26, 8:17 PM CDTFlash Flood WarningFSDPlymouth3 hr
Jun 26, 8:21 PM CDTSevere Thunderstorm WarningFSDPlymouth, Woodbury24 min
Jun 26, 8:32 PM CDTSevere Thunderstorm WarningFSDCherokee28 min
Jun 26, 8:41 PM CDTSevere Thunderstorm WarningFSDPlymouth, Woodbury34 min
Jun 26, 8:44 PM CDTSevere Thunderstorm WarningFSDIda, Woodbury31 min
Jun 26, 8:56 PM CDTSevere Thunderstorm WarningFSDBuena Vista34 min
Jun 26, 8:58 PM CDTHigh Wind WarningFSDBuena Vista, Cherokee, Clay, Dickinson, Ida, Lyon and 5 more4 hr
Jun 26, 8:59 PM CDTSevere Thunderstorm WarningFSDCherokee31 min
Jun 26, 9:02 PM CDTFlash Flood WarningFSDBuena Vista, Clay3 hr
Jun 26, 9:29 PM CDTSevere Thunderstorm WarningFSDBuena Vista31 min
Jun 26, 10:54 PM CDTAreal Flood WarningFSDCherokee, O'Brien, Plymouth, Sioux36 hr
Jun 27, 3:16 PM CDTRiver Flood WarningFSDWoodbury42 hr

Nearby

Flash Flood Warnings in Iowa, 2011Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.