TORNADOS Tornados are some of the most dangerouse weather in Minnesota. Tornados also called cyclones and twisters are charactirezed by Fujita-Pearson scale.

Life cycle-Tornados show certain characteristics from its birth to its death. The first sign is a strong whirlwind of dust from the suface ,also a small funnel forming from the storm cloud. The second stage the funnel becomes more stable and starts to desend towards the ground. The funnel almost always spins counter-clock wise but instances have been observed were it spins clok wise. It bounce over the ground and then finally dissaptes after a few minutes.

Causes-They are usally caused by instability in the atmosphere. Usally associted with advance of cold fronts. They can still ocour ahead of warm fronts and behind cold fronts. All the details on how the form is still unknown.

Description-Tornados are an area of low pressure. They are about 5-15 miles in diameter. With wind speeds from 150-500 mph.

Prevention and safety tips-Go to a strong safe place away from windows(example bathroom ,basement or stairwell). Dont try to run from them.

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The Fujita Scale F-Scale Number Intensity Phrase Wind Speed Type of Damage Done

F0--Gale tornado 40-72 mph Some damage to chimneys;breaks branches off trees; pushes over shallow- rooted trees; damages sign boards.

F1--Moderate tornado 73-112 mph The lower limit is the beginning of hurricane wind speed; peels surface off roofs; mobile homes pushed off foundations or overturned; moving autos pushed off the roads; attached garages may be destroyed.

F2--Significant tornado 113-157 mph 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 158-206 mph Roof and some walls torn off well constructed houses; trains overturned; most trees in fores uprooted

F4--Devastating tornado 207-260 mph Well-constructed houses leveled; structures with weak foundations blown off some distance; cars thrown and large missiles generated.

F5--Incredible tornado 261-318 mph Strong frame houses lifted off foundations and carried considerable distances to disintegrate; automobile sized missiles fly through the air in excess of 100 meters; trees debarked; steel re-inforced concrete structures badly damaged.