Thunderstorms and Tornadoes

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Thunderstorms and Tornadoes

• By Sara Gallant, Chelsea McCall and Alicia
  Bonventre

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What is a Thunderstorm?
Thunderstorm clouds are formed wherever there is
enough upward motion, instability in the
vertical, and moisture to produce a deep cloud
that reaches up to levels somewhat colder than
freezing.
Thunderstorms can occur at any time during the
year, but especially in the spring and summer
months. This is because the altitude of freezing
for water vapor is greater in warmer climates.
Thunderstorms occur most frequently in warmer
climates. Some of these places include South
Asia, Central Europe, New Mexico and Florida.
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What is a Tornado?
Tornadoes are generally formed from severe
thunderstorms resulting from interaction of warm
moist air from the South or Southwest and cool
dry air from the West or Northwest.
Thunderstorms develop in warm, moist air in
advance of eastward-moving cold fronts. These
thunderstorms often produce large hail, strong
winds, and tornadoes.
Tornadoes can occur at any time of the year. In
the southern areas, peak tornado occurrence is in
March through May, while peak months in the
northern areas are during the summer.
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Potential for Destruction
Tornadoes
The destructive power of tornadoes is rated by a
scale called the Fujita Tornado Damage Scale. A
category F0 tornado can do damage to chimneys,
break branches off of trees, push over
shallow-rooted trees and do damage to sign
boards. F1 tornadoes peel the surface off of
roofs, push mobile homes off of their foundations
and blow moving cars off of the road. An F2
tornado will tear the roofs off of houses,
demolish a mobile home, overturn boxcars, lift
cars off of the car and snap or uproot large
trees. F3 tornadoes do severe damage. They tear
walls and roofs off of well-constructed houses,
overturn trains, uproot trees in forests and lift
heavy cars off of the ground. A F4 tornado will
level a well-constructed house, weaken structure
foundations and blow cars around. Finally, a F5
tornado will lift a strong framed house, create
automobile sized missiles flying through the air
in excess of 100 meters. Trees are debarked and
incredible phenomena will occur.
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Potential for Destruction
Thunderstorms
Thunderstorms can cause disruptions in power,
gas, telephone, and even water supplies. These
disruptions can last from a few hours to a few
days, depending on the severity of the storm and
the damage that the storm leaves behind. In
addition, thunderstorms can spawn other disasters
such as flash floods and landslides.
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Tornadoes in Windsor
On June 17, 1946 Canada's third worst tornado in
history touched down in Windsor. It crossed the
Detroit river and into Windsor, killing 17 people
and destroying and damaging 400 homes in Windsor
and the surrounding county. The tornado also took
down 150 barns and farm buildings, and uprooted
hundreds of orchard trees and full-grown
woodlots. On April 3, 1974 deadly tornadoes hit
Windsor. Within eight hours, the tornado hit
Windsor as well as 11 states in the U.S. 323
people died in Windsor alone. The tornadoes
caused more than 1 billion dollars in damage. In
Windsor, one funnel cloud touched down at several
locations taking eight lives at the Windsor
Curling Club.
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Interesting Facts
On Wednesday, May 27, 1896 the worlds most
terrifying and destructive tornado touched down
in the St. Louis area.
The average thunder storm lasts 10-30min.
2000 thunderstorms occur worldwide at any given
moment
The U.S. has the most reported tornadoes of any
country
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Thunderstorms in Windsor
THE END!