tornadoes 1

8/6/2019 Tornadoes 1

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What is Tornadoes?

Are local storms of short duration that must be

ranked high among natures most destructive

forces.

Are violent windstorms that take the form of a

rotating column of air or vortex that extends

downward from a cumulonimbus cloud.

Did you know?April is the deadliest

month for tornadoes


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A tornado is a dark funnel-shaped cloud made

up of violently rotating winds that can reachspeeds of up to 300 m.p.h.

The diameter of a tornado can vary between a

few feet and a mile, and its track can extend

from less than a mile to several hundred miles. Tornadoes generally travel in a northeast

direction (depending on the prevailing winds) at

speeds ranging from 20-60 m.p.h.


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Tornadoes Take Many Shapes and Sizes

Weak Tornadoes

69% of all tornadoes

Less than 5% of tornado

deaths

Lifetime 1-10+ minutes

Winds less than 110 mph

Violent Tornadoes

Only 2% of all tornadoes

70% of all tornado deaths

Lifetime can exceed 1 hour

Lifetime can exceed 1 hour

Strong Tornadoes

29% of all tornadoes

Nearly 30% of all tornado deaths

May last 20 minutes or longer

Winds 110-205 mph


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What Causes a Tornado?

Tornadoes are most often spawned by giant

thunderstorms known as "supercells."

These powerful, highly organized storms form when

warm, moist air along the ground rushes upward,meeting cooler, drier air.

As the rising warm air cools, the moisture it carries

condenses, forming a massive thundercloud,

sometimes growing to as much as 50,000 ft. inheight.

Variable winds at different levels of the atmosphere

feed the updraft and cause the formation of the

tornado's characteristic funnel shape.


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These warm and colt air drafts collide and twist around each other, making

the cloud become a titanic mass of turbulent air or super cell. These giant

clouds can be 20 kilometres high and as much as 32 kilometres width. On the highest top the warm air will cool and condense, forming clouds. The

cool air goes down (this is known as downdraft) where it is getting warm

again.

So in fact it is a circular course of warm moist air and cooler, drier air. These

warm and colt air drafts collide and twist around each other, making the

cloud become a titanic mass of turbulent air or super cell. These giant clouds can be 20 kilometres high and as much as 32 kilometres

width.

Super cell


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Supercell in Tornadoes

A supercell is a thunderstorm that is

characterized by the presence of a

mesocyclone; a deep, continuously-rotating

updraft.[1

Of the four classifications of thunderstorms

(supercell, squall line, multi-cell, and single-cell),

supercells are the overall least common and

have the potential to be the most severe.

Supercells are often isolated from other

thunderstorms, and can dominate the local

climate up to 32 kilometres (20 mi) away.


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Supercells are often put into two classification

types: Low-precipitation (LP) and High-

precipitation (HP). LP supercells are usually found in climates that

are more arid, such as the high plains of the

United States,

HP supercells are most often found in moist

climates.

Supercells can occur anywhere in the world

under the right pre-existing weather conditions,but they are most common in the Great Plains of

the United States.


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