THE FUJITA SCALE

F Number

Wind Speed

Damage

0 (weak)

40 - 72 mph

light

1 ( weak)

73 - 112 mph

moderate

2 ( strong)

113 - 157 mph

considerable

3 (strong)

158 - 206 mph

severe

4 ( violent)

207 - 260 mph

devastating

5 (violent)

261 - 318 mph

incredible (rare)