Alert archive / Iowa / Flash Flood Warnings in 2012

Flash Flood Warning 3, NWS Des Moines, IA

April 14, 20126 counties in Iowa

NWS Des Moines, IA issued this flash flood warning at Apr 14, 2012, 7:30 PM CDT for 6 counties in Iowa. It was in force for 3 hr. 3 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
Apr 14, 2012, 7:30 PM CDT (00:30 UTC)
Expired
Apr 14, 2012, 10:33 PM CDT
In force
3 hr
Issued by
NWS Des Moines, IA
Area
Storm-based polygon
Flood severity
None

Counties Adair County, IA, Dallas County, IA, Guthrie County, IA, Madison County, IA, Polk County, IA, Warren County, IA

The radar

The Des Moines radar (KDMX), 26 km from the middle of the area, began a volume at 00:32 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
Apr 14, 8:15 PM CDTFLASH FLOODAnkeny, IA12 TO 18 INCHES OF WATER FLOWING ACROSS DELAWARE AVENUE NORTH OF ORALABOR ROAD.
Apr 14, 8:15 PM CDTHEAVY RAIN 2.755 Sw Saylorville Lake, IASTORM TOTAL RAINFALL AT 2.75 INCHES AS OF 815 PM. 1.9 INCHES FELL WITHIN 45 MINUTES.
Apr 14, 8:20 PM CDTFLASH FLOOD5 Nw Ankeny Airport, IASTREET FLOODING...1 TO 2 FEET IN ANKENY NEAR HY VEE AND HIGH SCHOOL BY 1ST STREET.

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, 0.5 hours before the alert went out and 217 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 2012-04-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2012-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 276 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
871 m above ground
0-6 km bulk shear
73 kt
0-1 km storm-relative helicity
276 m²/s²
0-3 km storm-relative helicity
483 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.0

Open this sounding in Storm Lab

The text

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

086 
WGUS53 KDMX 150030
FFWDMX
IAC001-049-077-121-153-181-150630-
/O.NEW.KDMX.FF.W.0003.120415T0030Z-120415T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
730 PM CDT SAT APR 14 2012

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHEASTERN ADAIR COUNTY IN SOUTHWEST IOWA...
  NORTHERN MADISON COUNTY IN SOUTH CENTRAL IOWA...
  NORTHERN WARREN COUNTY IN SOUTH CENTRAL IOWA...
  SOUTHEASTERN GUTHRIE COUNTY IN WEST CENTRAL IOWA...
  SOUTHERN DALLAS COUNTY IN CENTRAL IOWA...
  SOUTHERN POLK COUNTY IN CENTRAL IOWA...

* UNTIL 130 AM CDT SUNDAY

* AT 727 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  THUNDERSTORMS WITH VERY HEAVY RAINFALL MOVING INTO THE WARNED      
  AREA. AN ADDITIONAL ONE TO THREE INCHES OF RAIN IS LIKELY ACROSS   
  PARTS OF THE WARNED AREA.  

  THE FLASH FLOOD THREAT IS MAXIMIZED IN THE AREAS WHICH RECEIVED    
  HEAVY RAINFALL EARLIER.  THIS INCLUDES THE SOUTH SIDE OF DES       
  MOINES. 

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...DES
  MOINES...INDIANOLA...ADEL...ALTOONA...ANKENY...BONDURANT...
  CARLISLE...CLIVE...DALLAS CENTER...DE SOTO...EARLHAM...GRIMES...
  JOHNSTON...NORWALK...PLEASANT HILL...STUART...URBANDALE...WAUKEE...
  WEST DES MOINES AND WINDSOR HEIGHTS.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. TURN AROUND...DONT DROWN.

&&

LAT...LON 4149 9381 4143 9451 4161 9444 4162 9442
      4177 9345 4173 9335 4141 9332 4135 9333
      4135 9334 4130 9380

$$

JOHNSON
1 follow-up statement
021 
WGUS73 KDMX 150333
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1033 PM CDT SAT APR 14 2012

IAC001-049-077-121-153-181-150347-
/O.CAN.KDMX.FF.W.0003.000000T0000Z-120415T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WARREN IA-POLK IA-MADISON IA-GUTHRIE IA-ADAIR IA-DALLAS IA-
1033 PM CDT SAT APR 14 2012

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR SOUTHERN DALLAS...
NORTHEASTERN ADAIR...SOUTHEASTERN GUTHRIE...NORTHERN MADISON...
SOUTHERN POLK AND NORTHERN WARREN COUNTIES IS CANCELLED...

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.

ADDITIONAL THUNDERSTORMS WITH ADDITIONAL RAINFALL ARE POSSIBLE 
OVERNIGHT. A FLASH FLOOD WATCH IS IN EFFECT FOR A PORTION OF THE 
AREA UNTIL 10 AM SUNDAY.

LAT...LON 4149 9381 4143 9451 4161 9444 4162 9442
      4177 9345 4173 9335 4141 9332 4135 9333
      4135 9334 4130 9380

$$

ZOGG

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 14, 7:07 PM CDTFlash Flood WarningDMXAdair, Madison101 min
Apr 14, 7:11 PM CDTTornado WarningDMXMadison, Union19 min
Apr 14, 7:26 PM CDTSevere Thunderstorm WarningDMXClarke, Lucas, Madison, Marion, Union, Warren49 min
Apr 14, 7:32 PM CDTSevere Thunderstorm WarningDMXDallas, Jasper, Madison, Marion, Polk, Warren43 min
Apr 14, 7:37 PM CDTSevere Thunderstorm WarningDMXBoone, Dallas, Jasper, Polk, Story38 min
Apr 14, 7:37 PM CDTTornado WarningDMXClarke, Madison, Warren23 min
Apr 14, 8:10 PM CDTSevere Thunderstorm WarningDMXJasper, Marshall, Polk, Story50 min
Apr 14, 8:14 PM CDTSevere Thunderstorm WarningDMXClarke, Lucas, Mahaska, Marion, Monroe, Warren46 min
Apr 14, 8:33 PM CDTSevere Thunderstorm WarningDMXPoweshiek, Tama57 min
Apr 14, 8:43 PM CDTFlash Flood WarningDMXMarshall, Tama84 min
Apr 14, 8:55 PM CDTFlash Flood WarningDMXClarke, Decatur, Lucas, Marion, Monroe, Ringgold and 2 more103 min
Apr 14, 8:56 PM CDTSevere Thunderstorm WarningDMXLucas, Mahaska, Marion, Monroe, Wapello49 min
Apr 14, 9:21 PM CDTTornado WarningDMXMahaska24 min
Apr 14, 9:42 PM CDTSevere Thunderstorm WarningDMXWapello16 min
Apr 14, 10:25 PM CDTFlash Flood WatchDMXAdair, Adams, Audubon, Cass, Clarke, Dallas and 7 more7 hr
Apr 15, 4:15 AM CDTHigh Wind WarningDMXAdair, Adams, Audubon, Boone, Calhoun, Carroll and 19 more16 hr
Apr 15, 4:15 AM CDTWind AdvisoryDMXAppanoose, Black Hawk, Boone, Bremer, Butler, Calhoun and 29 more33 hr

Nearby

Flash Flood Warnings in Iowa, 2012Every flash flood warning in 2012

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.