What type of damage can they do?
The damage from tornadoes comes from the strong winds they contain. It is generally
believed that tornado wind speeds can be as high as 300 mph in the most violent
tornadoes. Wind speeds that high can cause automobiles to become airborne, rip
ordinary homes to shreds, and turn broken glass and other debris into lethal
missiles. The biggest threat to living creatures (including humans) from tornadoes
is from flying debris and from being tossed about in the wind.
What is the Fujita Tornado Damage Scale?
Dr. T. Theodore Fujita was a pioneer in the study of tornadoes and severe
thunderstorm phenomena. In 1971, he proposed the adoption of the Fujita Tornado
Damage Scale to provide estimates of tornado strength based on damage surveys.
Since it is extremely difficult to make direct measurements of tornado winds,
an estimate of the winds based on damage is the best way to classify them.
Fujita proposed a range of intensities zero to five, with weak tornadoes being
classified as "F0" and the strongest tornado as "F5". However, it is theoretically
possible to have a tornado with winds in excess of the F5 classification (318
mph). On May 3, 1999, an Oklahoma University Dobbler radar remotely sensed
tornado wind speeds above ground of 318 mph at Bridge Creek, Oklahoma, the
highest winds ever found near Earth's surface, and right at the threshold
of being F6 winds.
||Wind Estimate (mph)
Some damage to chimneys and TV antennas; breaks twigs off trees; pushes
over shallow-rooted trees.
Peels surface off roofs; windows broken; light trailer houses pushed or
overturned; some trees uprooted or snapped; moving automobiles pushed
off the road. 74 mph is the beginning of hurricane wind speed.
Roofs torn off frame houses leavin strong upright walls; weak buildings
in rural areas demolished; trailer houses destroyed; large trees snapped
or uprooted; railroad boxcars pushed over; light object missiles generated;
cars blown off highway.
Roofs and some walls torn off fram houses; some rural buildings completely
demolished; trains overturned; steel-framed hanger-warehouse-type structures
torn; cars lifted off the ground; most trees in a forest uprooted, snapped,
Whole frame houses leveled, leaving piles of bedris; steel structures
badly damaged; trees debarked by small flying debris; cars and trains
thrown some distances or rolled considerable distances; large missiles
Whole frame houses tossed off foundations; steel-reinforced concrete structures
badly damaged; automobile-sized missiles generated; trees debarked; incredible
phenomena can occur.
||319 to sonic
Should a tornado with the maximum wind speed in excess of F5 occur, the
extent and types of damage may not be conceived. A number of missiles
such as iceboxes, water heaters, storage tanks, automobiles, ect. will
create seriouse secondary damage on structures.