Alert archive / Iowa / Flash Flood Warnings in 2011

Flash Flood Warning 20, NWS Sioux Falls, SD

June 26, 2011Buena Vista County, Clay County, Iowa

NWS Sioux Falls, SD issued this flash flood warning at Jun 26, 2011, 9:02 PM CDT for Buena Vista County, Clay County, Iowa. It was in force for 3 hr. 2 reports 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, 9:02 PM CDT (02:02 UTC)
Expired
Jun 27, 2011, 12:00 AM CDT
In force
3 hr
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

Counties Buena Vista County, IA, Clay County, IA

The radar

The Des Moines radar (KDMX), 158 km from the middle of the area, began a volume at 02:01 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, 10:30 PM CDTFLASH FLOODStorm Lake, IASTREET FLOODING
Jun 26, 10:40 PM CDTFLASH FLOOD2 W Storm Lake, IAWATER OVER ROAD WITH VEHICLE WASHED INTO DITCH

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, 2.0 hours before the alert went out and 189 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°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.

181 
WGUS53 KFSD 270202
FFWFSD
IAC021-041-270500-
/O.NEW.KFSD.FF.W.0020.110627T0202Z-110627T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  BUENA VISTA COUNTY IN NORTHWEST IOWA
  SOUTHERN CLAY COUNTY IN NORTHWEST IOWA

* UNTIL MIDNIGHT CDT

* AT 900 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  THUNDERSTORMS WITH VERY HEAVY RAINFALL MOVING INTO THE WARNED 
  AREA. RAINFALL OF 1 TO 3 INCHES CAN BE EXPECTED WITH THESE STORMS
  HAS THEY MOVE ACROSS THE AREA.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...STORM
  LAKE...ALBERT CITY...ALTA...GREENVILLE...LAKESIDE...LINN GROVE...
  MARATHON...NEWELL...PETERSON...SIOUX RAPIDS...TRUESDALE AND WEBB.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 4255 9492 4256 9538 4262 9539 4304 9539
      4311 9493 4281 9490 4256 9491

$$

SCHUMACHER
3 follow-up statements
262 
WGUS73 KFSD 270311
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1011 PM CDT SUN JUN 26 2011

IAC021-041-270500-
/O.CON.KFSD.FF.W.0020.000000T0000Z-110627T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BUENA VISTA IA-CLAY IA-
1011 PM CDT SUN JUN 26 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHERN CLAY AND BUENA
VISTA COUNTIES UNTIL MIDNIGHT CDT...

AT 1004 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. 
DOPPLER RADAR ESTIMATED 1 TO 3 INCHES OF RAIN HAD ALREADY FALLEN 
ACROSS THE AREA. AN ADDITIONAL INCH OF RAIN IS POSSIBLE THROUGH 
MIDNIGHT. 

THROUGH 915 PM CDT...1.5 INCHES OF RAIN HAD FALLEN IN STORM LAKE.

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...STORM LAKE...ALBERT CITY...ALTA...GREENVILLE...LAKESIDE...
LINN GROVE...MARATHON...NEWELL...PETERSON...SIOUX RAPIDS...TRUESDALE
AND WEBB.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM THIS STORM 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 ALSO SUBJECT TO FLOODING.

&&

LAT...LON 4255 9492 4256 9538 4262 9539 4304 9539
      4311 9493 4281 9490 4256 9491

$$
SCHUMACHER
142 
WGUS73 KFSD 270336
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1036 PM CDT SUN JUN 26 2011

IAC021-041-270500-
/O.CON.KFSD.FF.W.0020.000000T0000Z-110627T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BUENA VISTA IA-CLAY IA-
1036 PM CDT SUN JUN 26 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHERN CLAY AND BUENA
VISTA COUNTIES UNTIL MIDNIGHT CDT...

AT 1032 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THUNDERSTORMS WITH RAINFALL ACROSS THE WARNED AREA. DOPPLER RADAR 
ESTIMATED 1 TO 3 INCHES OF RAIN ACROSS THE AREA. RAINFALL WILL BE 
GRADUALLY ENDING ACROSS THE AREA AS THE STORMS MOVES TO THE EAST. 
HOWEVER...EVEN AFTER THE RAIN ENDS...RUNOFF WILL CONTINUE TO CAUSE 
FLASH FLOODING OVER PORTIONS OF BUENA VISTA AND CLAY COUNTIES.

AT 1030 PM CDT...THE BUENA VISTA SHERIFF REPORTED STREET FLOODING IN 
STORM LAKE. 

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...STORM LAKE...ALBERT CITY...ALTA...GREENVILLE...LAKESIDE...
LINN GROVE...MARATHON...NEWELL...PETERSON...SIOUX RAPIDS...TRUESDALE
AND WEBB.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM THIS STORM 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 ALSO SUBJECT TO FLOODING.

&&

LAT...LON 4255 9492 4256 9538 4262 9539 4304 9539
      4311 9493 4281 9490 4256 9491

$$

SCHUMACHER
088 
WGUS73 KFSD 270501
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1201 AM CDT MON JUN 27 2011

IAC021-041-270514-
/O.EXP.KFSD.FF.W.0020.000000T0000Z-110627T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BUENA VISTA IA-CLAY IA-
1201 AM CDT MON JUN 27 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR SOUTHERN CLAY AND
BUENA VISTA COUNTIES WILL BE ALLOWED TO EXPIRE AT MIDNIGHT CDT...

EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. 
STREAMS AND CREEKS IN THE WARNED AREA HAVE RECEDED OR WERE BEGINNING 
TO RECEDE...AND NO ADDITIONAL REPORTS OF FLOODING HAVE BEEN REPORTED 
BY CLAY OR BUENA VISTA COUNTY LAW ENFORCEMENT. IF FLOODING HAS BEEN 
OBSERVED...PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 4255 9492 4256 9538 4262 9539 4304 9539
      4311 9493 4281 9490 4256 9491

$$

JH

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, 8:52 PM CDTFlash Flood WarningFSDCherokee2 hr
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, 9:29 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.