Alert archive / Iowa / Flash Flood Warnings in 2001

Flash Flood Warning 16, NWS Des Moines, IA

August 3, 20014 counties in Iowa

NWS Des Moines, IA issued this flash flood warning at Aug 3, 2001, 8:50 AM CDT for 4 counties in Iowa. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Aug 3, 2001, 8:50 AM CDT (13:50 UTC)
Expired: Aug 3, 2001, 1:00 PM CDT
In force: 4 hr
Issued by: NWS Des Moines, IA
Area: Whole counties; the outline is the Mesonet’s reconstruction

Counties Appanoose County, IA, Davis County, IA, Monroe County, IA, Wapello County, IA

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 1.8 hours before the alert went out and 202 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: 1095 J/kg
Mixed-layer CIN: -74 J/kg
Mixed-layer LCL: 622 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: 121 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 KDMX 031352
FFWDMX
IAC007-051-135-179-031800-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
850 AM CDT FRI AUG 3 2001

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  APPANOOSE COUNTY IN SOUTH CENTRAL IOWA
  MONROE COUNTY IN SOUTH CENTRAL IOWA
  DAVIS COUNTY IN SOUTHEAST IOWA
  WAPELLO COUNTY IN SOUTHEAST IOWA
  THIS INCLUDES THE CITY OF OTTUMWA

* UNTIL 100 PM CDT

* AT 839 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH FLASH FLOOD PRODUCING RAINS OVER MUCH OF
  MONROE AND APPANOOSE COUNTIES...WHICH WERE MOVING SLOWLY TO THE
  SOUTHEAST.  OTHER STORMS WERE OVER CENTRAL IOWA MOVING
  SOUTHEAST TOWARD THE WARNING AREA AS WELL.

* THUNDERSTORMS ARE CONTINUOUSLY REDEVELOPING OVER THE WARNING
  AREA...RESULTING IN EXCESSIVE RAINFALL.  RAINFALL RATES WILL
  AVERAGE 1 TO 2 INCHES PER HOUR.  FLOODING HAS ALREADY OCCURRED
  IN DAVIS AND WAPELLO COUNTY...AND WILL LIKELY SOON BEGIN IN
  APPANOOSE AND MONROE COUNTIES.  NATIONAL WEATHER SERVICE RADAR
  HAS ALREADY ESTIMATED BETWEEN 1 TO 6 INCHES IN THESE AREAS WITH
  SEVERAL ADDITIONAL INCHES POSSIBLE LATER THIS MORNING.

THIS WARNING EXTENDS THE FLASH FLOOD WARNING THAT WAS PREVIOUSLY IN
EFFECT FOR WAPELLO AND DAVIS COUNTIES.

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

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING ARjEA...LIVING NEAR THE AFFECTED
WATERWAYS...YOU SHOULD TAKE IMMEDIATE PRECAUTIONS TO PROTECT LIFE AND
PROPERTY.

LAT...LON 4114 9310 4060 9310 4061 9220 4115 9219

SMALL

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 3, 5:02 AM CDT	Flash Flood Warning	DMX	Davis	4 hr
Aug 3, 5:49 AM CDT	Flash Flood Warning	DMX	Calhoun, Pocahontas, Sac	6 hr
Aug 3, 6:06 AM CDT	Flash Flood Warning	DMX	Wapello	3 hr
Aug 3, 7:01 AM CDT	Severe Thunderstorm Warning	DMX	Greene	39 min

Nearby

Flash Flood Warnings in Iowa, 2001 Every flash flood warning in 2001

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.