As tornado season begins, the National Weather Service office in Grand Rapids points out that major tornadoes have become rare in Michigan.

A major F4 or F5 tornado hasn’t struck the Great Lakes State since April 2, 1977, or 40 years ago this week. However, there were 19 such storms in the 25 years prior to 1977, and the NWS warns that Michigan’s luck is unlikely to last.

Some may remember the destructive 1980 tornado that killed 5 people in Kalamazoo, injured 79, and did 50 million dollars in damage. However, that storm was an F3, which tops out at winds of 206 miles per hour.

An F5 is capable of producing winds in excess of 300 miles per hour.