Tornado Facts

Although tornadoes occur in many parts of the world, these destructive forces of nature are found most frequently in the United States east of the Rocky Mountains during the spring and summer months. In an average year, 1,000 tornadoes are reported nationwide, resulting in 75 deaths and over 1,500 injuries. Tornadoes are most likely to occur between 3 and 9 p.m., but have been known to occur at all hours of the day or night.

Tornadoes are categorized using the following F-scale (formulated by T. Theodore Fujita) based on wind strength and/or the amount of damage the tornado caused:

In Michigan 23% of all tornadoes have been rated F0, 40% have been rated F1, 26% have been rated F2, 7% have been rated F3, 3% have been rated F4, and less than 1% have been rated F5

A total of seven F5 tornadoes have occurred in Michigan since 1950. Of these seven, four have occurred in April. A total of thirty F4 tornadoes have occurred since 1950. 27 of the 30 struck in March through May.

Michigan averages 16 tornadoes per year, but the annual occurrence has ranged from as high as 39 to as low as 2. Michigan had 32 killer tornadoes between 1953 and 1991. This ranks 13th for killer tornadoes in the United States. Michigan had 236 tornado deaths during this time frame. This ranks 4th in the United States for the highest number of fatalities by state.

The deadliest Michigan tornado very recorded struck on June 8, 1953. It was rated an F5 that moved across Genesee and Lapeer counties, affecting the communities of Flushing, Flint and Lapeer. 115 people were killed along the 27 mile long track. This still ranks as the 9th deadliest tornado in U.S. history. A total of seven tornadoes struck Michigan that day. An additional 10 people were killed in the other tornadoes.

What to Listen For

TORNADO WATCH: Tornadoes are possible in your area. Remain alert for approaching storms.

TORNADO WARNING: A tornado has been sighted or indicated by weather radar. If a tornado warning is issued for your area and the sky becomes threatening, move to your pre-designated place of safety.

Tornado Frequency Map

Map displaying number of tornados by county from 1950 through 2004.

This map displays the total number of tornados by county from 1950 through 2004.


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  • Page last modified: 2-Aug-2007 4:59 PM UTC
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