Light damage. Damage to chimneys; break branches off trees; push over shallow-rooted trees; damage sign boards.
- (F1) Moderate Tornado (79 – 117 mph winds) – EF1 (86 – 110 mph winds)
Moderate damage. The lower limit is the beginning of hurricane wind speed; peel surface off roofs; mobile homes pushed off foundations or overturned; moving autos pushed off the road.
- (F2) Significant Tornado (118 – 161 mph winds) – EF2 (111 – 135 mph winds)
Considerable damage. Roofs torn off frame houses; mobile homes demolished; boxcars pushed over; large trees snapped or uprooted; light-object missiles generated.
- (F3) Severe Tornado (162 – 209 mph winds) – EF3 (136 – 165 mph winds)
Severe damage. Roofs and some walls torn off well-constructed houses; trains overturned; most trees in forest uprooted; heavy cars lifted off the ground and thrown.
- (F4) Devastating Tornado (210 – 261 mph winds) – EF4 (166 – 200 mph winds)
Devastating damage. Well-constructed houses leveled; structures with weak foundations blown off some distance; cars thrown and large missiles generated.
- (F5) Incredible Tornado (262 – 317 mph winds) – EF5 (> 200 mph)
Incredible damage. Strong frame houses lifted off foundations and carried considerable distance to disintegrate; automobile sized missiles fly through the air in excess of 100 meters (109 yds); trees debarked; incredible phenomena will occur.