Alert archive / Iowa / Tornado Warnings in 2001

Tornado Warning 28, NWS Des Moines, IA

April 11, 2001Black Hawk County, Iowa

NWS Des Moines, IA issued this tornado warning at Apr 11, 2001, 5:07 PM CDT for Black Hawk County, Iowa. It was in force for 23 min. 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: Apr 11, 2001, 5:07 PM CDT (22:07 UTC)
Expired: Apr 11, 2001, 5:30 PM CDT
In force: 23 min
Issued by: NWS Des Moines, IA
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Black Hawk County, IA

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 11, 4:00 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.1 hours before the alert went out and 166 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: 196 J/kg
Mixed-layer CIN: -182 J/kg
Mixed-layer LCL: 822 m above ground
0-6 km bulk shear: 63 kt
0-1 km storm-relative helicity: 336 m²/s²
0-3 km storm-relative helicity: 387 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.8

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KDMX 112208
TORDSM
IAC013-112230-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
507 PM CDT WED APR 11 2001

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  EASTERN BLACK HAWK COUNTY IN NORTHEAST IOWA

* UNTIL 530 PM CDT

* AT 504 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  TORNADO OVER LA PORTE CITY...OR ABOUT 15 MILES SOUTHEAST OF
  WATERLOO...MOVING NORTH AT 45 MPH.

* THE TORNADO WILL BE...
  NEAR LA PORTE CITY...AND RURAL EASTERN BLACK HAWK COUNTY NOW

THIS REPLACES THE SEVERE THUNDERSTORM WARNING PREVIOUSLY IN EFFECT 
FOR THIS PORTION OF BLACK HAWK COUNTY.

THE SAFEST PLACE TO %BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE.

LAT...LON 4229 9228 4230 9207 4264 9208 4264 9225

COGIL

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 11, 4:12 AM CDT	Severe Thunderstorm Warning	DMX	Adams, Cass, Taylor	38 min
Apr 11, 11:32 AM CDT	Tornado Warning	DMX	Ringgold	33 min
Apr 11, 12:00 PM CDT	Tornado Warning	DMX	Ringgold, Union	40 min
Apr 11, 12:19 PM CDT	Tornado Warning	DMX	Clarke	31 min
Apr 11, 12:29 PM CDT	Tornado Warning	DMX	Madison	46 min
Apr 11, 12:39 PM CDT	Tornado Warning	DMX	Dallas, Polk, Warren	51 min
Apr 11, 1:28 PM CDT	Tornado Warning	DMX	Polk	2 min
Apr 11, 1:46 PM CDT	Severe Thunderstorm Warning	DMX	Union	29 min
Apr 11, 1:50 PM CDT	Severe Thunderstorm Warning	DMX	Adair	40 min
Apr 11, 1:55 PM CDT	Severe Thunderstorm Warning	DMX	Crawford	35 min
Apr 11, 1:59 PM CDT	Tornado Warning	DMX	Audubon	31 min
Apr 11, 2:32 PM CDT	Tornado Warning	DMX	Greene, Guthrie	28 min
Apr 11, 2:36 PM CDT	Severe Thunderstorm Warning	DMX	Dallas	29 min
Apr 11, 2:48 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Polk	42 min
Apr 11, 2:58 PM CDT	Tornado Warning	DMX	Boone	32 min
Apr 11, 3:02 PM CDT	Tornado Warning	DMX	Calhoun, Greene, Webster	43 min
Apr 11, 3:02 PM CDT	Tornado Warning	DMX	Lucas, Marion	28 min
Apr 11, 3:18 PM CDT	Tornado Warning	DMX	Hamilton	32 min
Apr 11, 3:43 PM CDT	Tornado Warning	DMX	Jasper, Marshall	32 min
Apr 11, 3:45 PM CDT	Tornado Warning	DMX	Wright	45 min
Apr 11, 3:51 PM CDT	Tornado Warning	DMX	Franklin, Hamilton, Hardin	44 min
Apr 11, 4:02 PM CDT	Severe Thunderstorm Warning	DMX	Poweshiek	28 min
Apr 11, 4:05 PM CDT	Tornado Warning	DMX	Wapello	20 min
Apr 11, 4:23 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo	32 min
Apr 11, 4:27 PM CDT	Severe Thunderstorm Warning	DMX	Franklin	28 min
Apr 11, 4:31 PM CDT	Severe Thunderstorm Warning	DMX	Butler, Grundy	44 min
Apr 11, 4:35 PM CDT	Severe Thunderstorm Warning	DMX	Tama	30 min
Apr 11, 4:43 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk	37 min
Apr 11, 5:01 PM CDT	Severe Thunderstorm Warning	DMX	Bremer	39 min

Nearby

Tornado Warnings in Iowa, 2001 Every tornado warning in 2001 Tornadoes 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.