A strong upper level low pressure lifted northeast out of the southern Plains during the afternoon of the 6th.  During the heating of the afternoon, thunderstorms erupted in the unstable air.  The freezing level was around 15,000 feet, so hail was not a great threat.  Surface dew point temperatures were in the upper 60s to low 70s with precipitable water values around 1.75 inches.  Thunderstorms fired southwest of the Des Moines metropolitan area.  A tornado touched down in rural Madison County.  The tornado was about 60 feet wide and produced a half mile long path of damage in open country.    As the storms moved northeast they continued to intensity.  One cell dropped a tornado at the Glen Oaks Golf Course in West Des Moines, causing some minor damage there.  The tornado tracked northeast and flipped a semi tractor-trailer truck in Interstate 35 resulting in one injury.  It continued northeast and hit an apartment complex causing damage to the building and destroying an 8-car garage.  The path was more intermittent as it continued northeast into the city.  There were numerous reports of trees and power lines being downed.  The tornado lifted as the event transitioned into a high wind event.  The storms produced wind damage in Johnston as it moved through the area.  High winds of 80 to 85 MPH occurred in northern Polk and southern Story Counties before they weakened.  A grain bin was flattened, along with tree and crop damage, as the storm moved through the Elkhart area.  Just northwest of that, in Slater, high winds took the roof off of a house in southern Story County.  One person in the house was injured.  The storms continued to track northeast, eventually dropping another tornado in Butler and Bremer Counties.  The tornado had a somewhat intermittent track touching down south of Shell Rock and lifting northeast of Waverly.  For the most part the tornado tracked through corn fields there.  One farmstead was hit in Butler County.  A grain bin was destroyed and blown one quarter of a mile across a field, another was blown off its foundation, a shed was destroyed, and crops were damaged.  In Bremer County, one car and a garage were damaged along the tornadoes path.  Another farmstead was hit north of Waverly.  Part of a machine garage was destroyed and blown about 30 feet off of its foundation.

Thunderstorm Wind in POLK, IOWA
From 06-SEP-01 14:50:00 to 06-SEP-01 14:50:00 (CST)
Location: JOHNSTON
Magnitude: 50 E
Property damage: 5K
Reported by: LAW ENFORCEMENT

Thunderstorm Wind in POLK, IOWA
From 06-SEP-01 15:00:00 to 06-SEP-01 15:00:00 (CST)
Location: ANKENY
Magnitude: 52 E
Property damage: 10K
Reported by: LAW ENFORCEMENT

Thunderstorm Wind in POLK, IOWA
From 06-SEP-01 15:05:00 to 06-SEP-01 15:05:00 (CST)
Location: ELKHART
Magnitude: 70 E
Property damage: 50K
Crop damage: 5K
Reported by: BROADCAST MEDIA

Thunderstorm Wind in STORY, IOWA
From 06-SEP-01 15:10:00 to 06-SEP-01 15:10:00 (CST)
Location: SLATER
Magnitude: 80 E
Property damage: 75K
Crop damage: 10K
Reported by: BROADCAST MEDIA

Tornado in BREMER, IOWA
From 06-SEP-01 16:43:00 to 06-SEP-01 17:07:00 (CST)
Location: WAVERLY
Tornado F-scale: F2
Property damage: 100K
Crop damage: 10K
Reported by: EMERGENCY MANAGER

Tornado moved in from Butler County and touched down again, mostly in open field.  A car and garage was damaged in Bremer County.

Tornado in BUTLER, IOWA
From 06-SEP-01 16:39:00 to 06-SEP-01 16:43:00 (CST)
Location: SHELL ROCK
Tornado F-scale: F1
Property damage: 75K
Crop damage: 10K
Reported by: TRAINED SPOTTER

Tornado hit grain bin and blew downwind 1/4 mile.  Shed was destroyed on a farm south of Shell Rock.  Tornado moved into Bremer County.

Thunderstorm Wind in BUTLER, IOWA
From 06-SEP-01 16:30:00 to 06-SEP-01 16:30:00 (CST)
Location: SHELL ROCK
Magnitude: 52 E
Property damage: 5K
Reported by: TRAINED SPOTTER

Tornado in MADISON, IOWA
From 06-SEP-01 13:52:00 to 06-SEP-01 13:52:00 (CST)
Location: PERU
Tornado F-scale: F0
Crop damage: 1K
Reported by: LAW ENFORCEMENT

Damage in a convergent path in field.

Tornado in POLK, IOWA
From 06-SEP-01 14:34:00 to 06-SEP-01 14:41:00 (CST)
Location: WEST DES MOINES
Tornado F-scale: F1
Property damage: 500K
Crop damage: 5K
Reported by: LAW ENFORCEMENT

Tornado touched down on southwest edge of West Des Moines at the Glen Oaks Golf Club and swept into an apartment complex.  Track was intermittent following the destruction of a garage unit there.