Tornado Damage Classification
Wind: 40-72 miles per hour (mph)
Light Damage: Some chimneys damaged, twigs and branches
broken off trees, shallow-rooted trees pushed over, signboards damages,
some windows broken
F1--Weak
Wind: 73-112 mph
Moderate Damage: Surface of roofs peeled off, mobile
homes pushed off foundations or overturned, outbuildings demolished,
moving autos pushed off the roads, trees snapped or broken; beginning of
hurricane speed winds
Wind: 113-157 mph
Considerable Damage: Roofs torn off frame houses, mobile
homes demolished, frame houses with weak foundations lifted and moved,
large trees snapped or uprooted, light-object missiles generated
F3--Strong
Wind: 158-206 mph
Severe Damage: Roofs and some walls torn off
well-constructed houses; trains overturned; most trees in forecast
uprooted, heavy cars lifted off the ground and thrown, weak pavement
blown off the roads
Wind: 207-260 mph
Devastating Damage: Well-constructed houses leveled,
structures with weak foundations blown off the distance, cars thrown and
disintegrated, trees in forest uprooted and carried some distance away
F5--Violent
Wind: 261-318 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 300 feet,
trees debarked, incredible phonomena will occur
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