August 8–9, 1993, tornado outbreak
| Type | Tornado outbreak |
|---|---|
| Duration | August 8–9, 1993 |
| Tornadoes confirmed | 7 |
| Max rating1 | F2 tornado |
| Duration of tornado outbreak2 | ~ 1 day, 20 hours |
| Damage | Approximately 1.22 million (tornadic damages only) |
|
1Most severe tornado damage; see Fujita scale 2Time from first tornado to last tornado | |
The August 8–9, 1993, tornado outbreak was a small tornado outbreak that occurred over the Upper Midwest of the United States for a period of two days. An F0 tornado near Littlefork, Minnesota lifted and moved a mobile home, killing its two occupants. It is Minnesota's most recent single tornado to cause multiple deaths. Other minor tornadoes occurred in Minnesota, Iowa and Wisconsin, causing limited damage.
Meteorological synopsis
At about 6:00 PM CST (23:00 UTC) a sea-level cyclone and occluded front were located over North Dakota.[1] Observations from International Falls showed the tropopause was at 39,800 feet (12,100 m), while observations from Bismark recorded it at 39,000 feet (12,000 m).[1] Lifted Indices (LI) at the time CDT were also low, and thunderstorms were starting to develop in the Eastern Dakotas.[1] In response to the storms, the National Severe Storms Forecast Center (NSSFC) issued a tornado watch for the eastern Dakotas.[1] At 11:55 PM CST (0440 UTC) the outbreak's first confirmed tornado was reported near Gully, Minnesota. As a result of the tornado a Tornado Warning was issued for Clearwater County; the storm's next location.[1][2] Ten minutes later at 12:05 PM CST (0450 UTC) another tornado, rated an F0, was reported near Roseau, Minnesota.[1][3] After the two August 8th tornadoes, most local warnings were allowed to expire, as local radar did not determine any of the storms to be severe.[1] During the early morning hours of August 9 Duluth radar indicated multicellular convection near the Littlefork, Minnesota area that was associated with an outflow boundary from the earlier Dakota storms.[1] At 1:35 AM CST (0735 UTC) a deadly F0 tornado touched down unexpectedly near Littlefork, in association with the multicellular thunderstorm.[4] Unstable air from the day before persisted over much of the upper Midwest, and allowed storms to form over much of the area. On the night of August 9th the strongest tornado of the outbreak, an F2, occurred near New Hampton injuring 2 people.[5] Another cluster of thunderstorms occurred over Wisconsin, producing 3 relatively minor tornadoes.[6]
Confirmed tornadoes
| F0 | F1 | F2 | F3 | F4 | F5 | Total |
|---|---|---|---|---|---|---|
| 5 | 1 | 1 | 0 | 0 | 0 | 7 |
August 8 event
| List of confirmed tornadoes – August 8, 1993 | ||||||
|---|---|---|---|---|---|---|
| | | | | | | |
| Minnesota | ||||||
| F0 | S of Gully | Polk | 47°26′N 95°23′W / 47.44°N 95.38°W | 0440 | .10 miles (0.2 km) | Brief touchdown, tornado uprooted trees and damaged some buildings.[2] |
| F0 | N of Roseau | Roseau | 48°31′N 95°27′W / 48.52°N 95.45°W | 0450 | .10 miles (0.2 km) | Brief touchdown that damaged a warehouse, total damage $500,000 USD.[3] |
| Sources: NCDC Storm Events Database tornado list August 8, 1993.[7] | ||||||
August 9 event
| List of confirmed tornadoes – August 9, 1993 | ||||||
|---|---|---|---|---|---|---|
| | | | | | | |
| Iowa | ||||||
| F2 | W of New Hampton | Chickasaw County | 43°02′N 92°16′W / 43.04°N 92.27°W | 2240 | 5 miles (8.0 km) | Injured 2 people and caused $550,000 USD in damages.[5] |
| Minnesota | ||||||
| F0 | SW of Littlefork | Koochiching | 48°14′N 93°17′W / 48.24°N 93.28°W | 0735 | 1.25 miles (2.0 km) | 2 deaths - see section on this tornado |
| Wisconsin | ||||||
| F0 | SE of Fifield | Price County | 45°29′N 90°54′W / 45.49°N 90.9°W | 0015 | .30 miles (0.5 km) | Caused $5,000 USD in crop damage[8] |
| F1 | E of Phillips | Price County | 45°29′N 90°54′W / 45.49°N 90.9°W | 0100 | .50 miles (0.8 km) | The tornado ripped a roof off a barn and uprooted trees causing $55,000 USD in total damage.[6][9] |
| F0 | N of Tripoli | Oneida County | 45°20′N 90°00′W / 45.34°N 90.00°W | 0115 | .30 miles (0.5 km) | Caused limited damage of $500 USD.[9] |
| Sources: NCDC Storm Events Database tornado list August 9, 1993.[7] | ||||||
Littlefork tornado
The tornado near Littlefork lifted a mobile home and moved it .25 miles (0.4 km) to the northeast of the original site. The two occupants of the home were killed and the tornado caused $50,000 USD in damage.[4] National Weather Service officials first believed the tornado to be "straight-line winds", but after an investigation they determined that a tornado had occurred at the site.[10]
References
- 1 2 3 4 5 6 7 8 Packingham, Dean. "The Littlefork Tornado: A Post-Event Analysis". National Weather Service Office Duluth. Retrieved 7 March 2010.
- 1 2 "Event Record Details". National Climatic Data Center (NCDC). Retrieved 4 March 2010.
- 1 2 "Event Record Details". National Climatic Data Center (NCDC). Retrieved 4 March 2010.
- 1 2 "Event Record Details". National Climatic Data Center (NCDC). Retrieved 4 March 2010.
- 1 2 "Event Record Details". National Climatic Data Center (NCDC). Retrieved 4 March 2010.
- 1 2 "Event Record Details". National Climatic Data Center (NCDC). Retrieved 5 March 2010.
- 1 2 "Storm Events". National Climatic Data Center (NCDC). Archived from the original on 1 April 2010. Retrieved 2 March 2010.
- ↑ "Event Record Details". National Climatic Data Center (NCDC). Retrieved 5 March 2010.
- 1 2 "Event Record Details". National Climatic Data Center (NCDC). Retrieved 5 March 2010.
- ↑ "Couple killed as tornado slams into Minnesota". Duluth News-Tribune (The Spokesman-Review). August 10, 1993. Retrieved 7 March 2010.