Northeast Iowa - Southeast Minnesota Tornadoes of June 11, 2004 (original) (raw)
La Crosse, WI
Weather Forecast Office
Overview
| A small, but intense Supercell formed along a warm front that was stretched across southern Minnesota and northern Iowa on Friday afternoon, June 11, 2004. It initially developed near Charles City, IA and then tracked northeast into Howard County, Iowa. From that point on it began to produce a series of tornadoes as it moved north toward the state line. No other damage could be found as the storm tracked north until it approached the Riceville, IA area where it dropped another brief touchdown. A few sheds and buildings on the east side of Riceville were damaged, with mainly tin blown off roofs and siding torn off. This damage was rated F0 and the approximate time was 5:35 p.m. A much more significant tornado formed around 5:50 p.m. about 4 miles north of Riceville or 4 miles southwest of Le Roy, Minnesota, just east of the Mitchell-Howard County line. The tornado formed in open fields near County Road A23 just east of Addison Avenue, which is the Mitchell-Howard County line. It hit several homes and farms (F2 damage) as it tracked straight north toward the Minnesota-Iowa state line, only feet from the county line. One home lost the roof and all outbuildings, while another home right on the state line was completely destroyed. The tornado was approx. 150 yards wide at times and apparently reached low end F3 damage intensity right on the state line around 6:00 p.m. The tornado then started to weaken but did heavy damage to a grain company (Koch Industries)(F2 damage) about 2 miles west of Le Roy and continued north crossing Highway 56 just before 6:15 p.m.. The tornado lifted approximately 4 miles northwest of Le Roy in open fields. There were also brief tornado touch downs (all rated F0) near Dexter and Le Roy, Minnesota, as well as areas along the Mower-Fillmore County line west of Spring Valley. |  Tornado map from June 11, 2004 |
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Tornadoes:
Tornado - New Haven, IA
Mitchell County
| Date | June 11, 2004 |
|---|---|
| Time (Local) | 5:17-5:33 p.m. |
| EF Rating | F1 |
| Est. Peak Winds | |
| Path Length | 4 miles |
| Max Width | 60 yards |
| Injuries/Deaths | 0 / 0 |
| Summary: A small but intense supercell thunderstorm produced three tornadoes in northeast Iowa. The first tornado touched down about 4 miles southeast of New Haven (Mitchell County), south of 320th Street and between Walnut and Windfall Avenue. It tracked north, primarily in open fields, and lifted between 350th and 360th Street east of New Haven, or just west of Windfall Avenue. |
Track Map
Tornado - Riceville, IA
Howard County
| Date | June 11, 2004 |
|---|---|
| Time (Local) | 5:40-5:50 p.m. |
| F Rating | F0 |
| Est. Peak Winds | |
| Path Length | 4 miles |
| Max Width | 40 yards |
| Injuries/Deaths | 0 / 0 |
| Summary: The second tornado touched down just east of the Mitchell-Howard County line, about 4 miles south of Riceville, and also moved straight north. It downed a few trees, but primarily crossed open fields until it reached the southeast side of Riceville. It damaged a few sheds and buildings in Riceville, with mainly tin roofing material and siding blown off before lifting while in town. |
Track Map
Tornado - LeRoy, MN
Howard & Mower Counties
| Date | June 11, 2004 |
|---|---|
| Time (Local) | 5:56-6:13 p.m. |
| F Rating | F3 |
| Est. Peak Winds | |
| Path Length | 12 miles |
| Max Width | 150 yards |
| Injuries/Deaths | 0 / 0 |
| Summary: The third and most significant tornado formed about 2 miles north of Riceville, again just east of the Mitchell-Howard County line. The tornado tracked north, just east of the county line or Addison Avenue. It grew in strength and at one point was approximately 150 yards wide, hitting several homes and farms (F2 damage). One home lost the roof and all buildings. The tornado was so close to the county line that debris was thrown across Addison Avenue into Mitchell County at times. The dirt and young crops were scoured by the tornado. The tornado crossed into Minnesota just southwest of Le Roy (Mower County), hitting a home directly on the state line. The home, which was built in1900, and several buildings on the lot, were completely demolished (F3 damage). |
Track Map
Tornado - LeRoy, MN
Fillmore County
| Date | June 11, 2004 |
|---|---|
| Time (Local) | 6:30-6:32 p.m. |
| F Rating | F0 |
| Est. Peak Winds | |
| Path Length | 0.2 miles |
| Max Width | 20 yards |
| Injuries/Deaths | 0 / 0 |
| Summary: A brief tornado touched down near LeRoy from a squall line that moved through from the west. |
Track Map
Tornado - 2 miles NE of Dexter, MN
Mower County
| Date | June 11, 2004 |
|---|---|
| Time (Local) | 6:53-6:55 p.m. |
| F Rating | F0 |
| Est. Peak Winds | |
| Path Length | 0.2 miles |
| Max Width | 20 yards |
| Injuries/Deaths | 0 / 0 |
| Summary: A brief tornado touchdown was reported as a squall line moved through. |
Track Map
The Enhanced Fujita (EF) Scale classifies tornadoes into the following categories:
| EF0 Weak 65-85 mph | EF1 Moderate 86-110 mph | EF2 Significant 111-135 mph | EF3 Severe 136-165 mph | EF4 Extreme 166-200 mph | EF5 Catastrophic 200+ mph |
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