Tornadoes in Moore, Oklahoma, are neither new nor uncommon. Monday's massive twister may be the worst the city has seen, but it's also the 22nd recorded by the National Weather Service since 1890.

We put the data for all 22 on the map below, including estimates for Monday's size and toll. All paths are approximate, but each is the correct length in miles. Markers indicate no known path.

Here's how to read it.

  • The color of the line or marker indicates the time period in which the tornado struck. Lavender is prior to 1900. Red is from 1900 to 1990. Green is from 1990 to 2000. Blue is from 2000 onward. A black line indicates that the tornado resulted in fatalities. (Monday's tornado is the large swath beginning in the southwest of town; the confirmed death toll was lowered to 24 on Tuesday.)
  • The width of the line correlates to its strength. The heaviest lines denote F5 or EF5 tornadoes. The thinnest lines are either F0 or predate the Fujita scale.
  • Clicking on any line or marker will provide more information about its size, strength, width, and toll.

There are a number of small, short tornadoes that did little damage. Zoom in to see them.

The overall impression one gets is clear. Moore, Oklahoma, is in the heart of tornado alley. About 120 years ago, the first recorded tornadoes struck. Since 1937, the longest the city has gone without a tornado is 16 years — but since 1991, it's averaged one every two-and-a-half.