Alert archive / Iowa / Flash Flood Warnings in 2011

Flash Flood Warning 25, NWS Des Moines, IA

June 25, 2011Clarke County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jun 25, 2011, 7:23 AM CDT for Clarke County, Iowa. It was in force for 6 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 25, 2011, 7:23 AM CDT (12:23 UTC)
Expired: Jun 25, 2011, 1:30 PM CDT
In force: 6 hr
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Flood severity: None

County Clarke County, IA

The radar

The Des Moines radar (KDMX), 83 km from the middle of the area, began a volume at 12:25 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

Time	Report	Where	Remark
Jun 25, 10:55 AM CDT	FLASH FLOOD	1 S Osceola, IA	SEVERAL CLOSURES ALONG HWY 69 SOUTH OF OSCEOLA DUE TO WATER OVER ROADWAY.

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

The nearest sounding before it

Topeka, KS (KTOP), launched 12:00Z, 0.4 hours before the alert went out and 273 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: 2176 J/kg
Mixed-layer CIN: -260 J/kg
Mixed-layer LCL: 859 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 238 m²/s²
0-3 km storm-relative helicity: 189 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.1

Open this sounding in Storm Lab

The text

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

593 
WGUS53 KDMX 251223
FFWDMX
IAC039-251830-
/O.NEW.KDMX.FF.W.0025.110625T1223Z-110625T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
723 AM CDT SAT JUN 25 2011

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CLARKE COUNTY IN SOUTH CENTRAL IOWA...

* UNTIL 130 PM CDT SATURDAY

* AT 723 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  SLOW MOVING THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE   
WARNED AREA. UP TO 2 INCHES OF RAIN HAS FALLEN IN THE LAST 90 
MINUTES.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  OSCEOLA.

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 4114 9401 4104 9356 4089 9356 4089 9360
      4090 9360 4090 9401

$$

4 follow-up statements

656 
WGUS73 KDMX 251346
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
846 AM CDT SAT JUN 25 2011

IAC039-251830-
/O.CON.KDMX.FF.W.0025.000000T0000Z-110625T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARKE IA-
846 AM CDT SAT JUN 25 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR CLARKE COUNTY UNTIL 130
PM CDT...

AT 843 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS SOUTHEAST IOWA.  THE 
HEAVY RAIN PRODUCING STORMS HAD MOVED SOUTHEAST OF THE WARNED AREA.  
ADDITIONAL HEAVY RAINFALL IS NOT EXPECTED SO CONDITIONS SHOULD 
SLOWLY IMPROVE THIS MORNING. 


RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO 
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING 
INCLUDE...THE WHITE BREAST CREEK SOUTH OF WOODBURN.  THIS AREA IS 
VULNERABLE TO FLASH FLOODING AND IT SHOULD BE IMPACTED THIS MORNING. 


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 4114 9401 4104 9356 4089 9356 4089 9360
      4090 9360 4090 9401

$$

JOHNSON

631 
WGUS73 KDMX 251443
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
943 AM CDT SAT JUN 25 2011

IAC039-251830-
/O.CON.KDMX.FF.W.0025.000000T0000Z-110625T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARKE IA-
943 AM CDT SAT JUN 25 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR CLARKE COUNTY UNTIL 130
PM CDT...

AT 940 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THAT THE HEAVY RAIN PRODUCING THUNDERSTORMS HAD MOVED OUT OF THE 
WARNED AREA.  ADDITIONAL HEAVY RAINFALL IS NOT EXPECTED THIS MORNING 
SO FLASH FLOOD CONDITIONS SHOULD IMPROVE THROUGH THE NOON HOUR. 

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL LIKELY CAUSE FLASH FLOODING 
TO OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING 
INCLUDE...THE WHITE BREAST CREEK SOUTH OF WOODBURN.  THIS AREA IS 
VULNERABLE TO FLASH FLOODING AND IT SHOULD BE IMPACTED THIS MORNING. 
SECONDARY ROADS WILL BE MOST VULNERABLE AND SHOULD BE AVOIDED THIS 
MORNING. 

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 4114 9401 4104 9356 4089 9356 4089 9360
      4090 9360 4090 9401

$$

212 
WGUS73 KDMX 251618
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1118 AM CDT SAT JUN 25 2011

IAC039-251830-
/O.CON.KDMX.FF.W.0025.000000T0000Z-110625T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARKE IA-
1118 AM CDT SAT JUN 25 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR CLARKE COUNTY UNTIL 130
PM CDT...

AT 1100 AM CDT...THE HEAVY RAINFALL HAD ENDED IN THE WARNED AREA AND 
NO ADDITIONAL RAINFALL IS EXPECTED.  RUNOFF FROM THE HEAVY RAIN 
EARLY THIS MORNING WILL CONTINUE TO CAUSE FLASH FLOOD BUT CONDITIONS 
SHOULD SLOWLY IMPROVE THROUGH THE NOON HOUR. 

LAW ENFORCEMENT REPORTED THAT NUMEROUS COUNTY ROADS HAD WATER OVER 
THEM DUE TO FLASH FLOODING IN SOUTHERN CLARKE COUNTY.  HIGHWAY 69 
SOUTH OF OSCEOLA HAD BRIDGES WHICH WHERE FLOODED DUE TO FLASH 
FLOODING. 

A VULNERABLE AREA IN SOUTHEAST CLARKE COUNTY IS WHITE BREAST CREEK 
SOUTH OF WOODBURN. THIS AREA IS VULNERABLE TO FLASH FLOODING AND IT 
SHOULD BE IMPACTED THROUGH THE NOON HOUR. . 

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 4114 9401 4104 9356 4089 9356 4089 9360
      4090 9360 4090 9401

$$

378 
WGUS73 KDMX 251832
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
132 PM CDT SAT JUN 25 2011

IAC039-251847-
/O.EXP.KDMX.FF.W.0025.000000T0000Z-110625T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARKE IA-
132 PM CDT SAT JUN 25 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR CLARKE COUNTY HAS
BEEN ALLOWED TO EXPIRE...

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...ENDING THE FLOOD THREAT. IF FLOODING HAS BEEN OBSERVED...
PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 4114 9401 4104 9356 4089 9356 4089 9360
      4090 9360 4090 9401

$$

JOHNSON

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 25, 5:07 AM CDT	Severe Thunderstorm Warning	DMX	Adams, Union	38 min
Jun 25, 5:44 AM CDT	Severe Thunderstorm Warning	DMX	Clarke	30 min
Jun 25, 5:51 AM CDT	Flash Flood Warning	DMX	Adams, Cass, Union	6 hr
Jun 25, 9:11 AM CDT	Flash Flood Warning	DMX	Appanoose, Wayne	4 hr
Jun 25, 11:30 AM CDT	River Flood Warning	DMX	Decatur	21 hr
Jun 25, 11:30 AM CDT	River Flood Warning	DMX	Appanoose, Wayne	29 hr

Nearby

Flash Flood Warnings in Iowa, 2011 Every 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.