F2 tornado, Aurora, Iowa, September 6, 2001

1. F040 to 72 mph

   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 mphthis tornado

   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

F2

Date

September 6, 2001

Touchdown

6:30 PM CDT (23:30 UTC)

Path length

1.0 miles (1.6 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$300,000

County

Buchanan County

Touchdown point

42.620, -91.730

Lift-off point

42.620, -91.720

Record number

1129

Event Summary for 09/06/01:A strong short wave trough in the upper level atmosphere, moved northeast through Iowa and Wisconsin during the afternoon and evening hours. This wave of energy helped thunderstorms, which were moving along a warm front in northeast Iowa, become strong. Despite the lack of convective available potential energy, ample moisture and wind shear along the front allowed thunderstorms within this area of rain to rotate and produce a few short lived tornadoes. One storm in Buchanan County Iowa, produced two tornadoes as it quickly moved northeast along the warm front.Here is a summary of the tornadoes which struck northeastern Buchanan County Iowa.At 605 pm CDT, an F0 tornado touched down 5 miles southwest of Aurora, Iowa, producing damage to the Ralph Kramer farm site. Several out buildings were damaged or destroyed. One empty grain bin was moved off of its foundation. The home only had minor damage, with some siding blown off. The tornado continued moving northeast, producing crop and tree damage as it crossed 142 street. At 625 pm, the tornado struck the Lonnie McAllister farm site, again damaging or destroying farm out buildings. This is also where the most significant crop damage was observed. The tornado then lifted, leaving a trail of some tin and other debris, as the storm moved northeast. This tornado was on the ground for 3.5 miles and was 40 yards wide at its widest point.At 630 pm CDT, an F2 tornado touched down 0.25 miles southwest of Aurora and quickly moved across Aurora, producing damage to the roof of the American Legion building in Aurora. The tornado then struck the Ken Mosher home just east of Aurora. The tornado totally ripped off the roof and two car garage of this newer frame dwelling. The tornado then lifted 0.75 miles northeast of Aurora, and no other tornadoes from this storm touched down again until it had moved about a mile north into Fayette County, Iowa. This tornado was on the ground for 1 mile, and was 50 yards wide.

Tornado reported by emergency manager

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

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

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 General Thunderstorms Risk. The outlook in force was issued at 20:12 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.

The La Crosse radar (KARX), 141 km away, was scanning. The volume nearest the touchdown began at 23:31 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

7 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.