F0 tornado, Kinross, Iowa, April 11, 2001

1. F040 to 72 mphthis tornado

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. F173 to 112 mph

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. F2113 to 157 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. F3158 to 206 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. F4207 to 260 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. F5261 to 318 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

F0

Date

April 11, 2001

Touchdown

4:25 PM CDT (21:25 UTC)

Path length

3.0 miles (4.8 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$90,000

County

Keokuk County

Touchdown point

41.430, -92.030

Lift-off point

41.470, -92.000

Record number

708

Summary of 4/11/01 event: (For additional details, see individual reports for the date.)Strong surface low pressure lifted from western Kansas into Minnesota during the event. A trailing dryline also moved eastward across Iowa. Additionally, dewpoints in the mid 60s, and extreme wind shear made the environment ripe for rotating supercells. Tornado watches issued by the Storm Prediction Center highlighted the "particularly dangerous" nature of the situation. Numerous funnel clouds and tornados occurred during the event across eastern Iowa. Most of the tornadic activity involved brief touchdowns of F0 tornados. Houses, outbuildings, and trees sustained damage throughout the area, but there were no injuries reported during the event. There were also isolated reported of small pea size hail, and 50 to 55 mph winds in extreme northwest Illinois.

An F0 tornado tracked from southwest of Kinross into the community. The public also reported several funnel clouds near the tornado. The tornado damaged farm out buildings. In Kinross, several house were damaged significantly, and many others had roof and siding damage. A shed housing two cars was also destroyed. There was substantial damage to trees and an orchard in the town. There were no injuries.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

8 minutes of warning. NWS DVN issued a tornado warning for this county at 21:17 UTC, 8 minutes before the tornado touched down, in force until 21:45 UTC.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a High Risk. The outlook in force was issued at 20:21 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Washington (AWG), 34 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The Quad Cities radar (KDVN), 121 km away, was scanning. The volume nearest the touchdown began at 21:24 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

The live radar over the trackEvery 2001 tornado in IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are

49 more were confirmed in the United States that day.

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.