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A Tornado<br />

Tornadoes<br />

Tornadoes, or twisters, are the fastest winds<br />

on Earth. The storm clouds are a funnel<br />

shape, and they spin down from<br />

thunderclouds. When the tornado<br />

touches the ground, it starts to move<br />

like a vacuum cleaner, sucking up<br />

things from the ground. Tornadoes<br />

move quite slowly, at a<strong>bo</strong>ut<br />

40 kilometers per hour, but<br />

winds inside the funnel can<br />

have speeds of up to 800<br />

kilometers per hour!<br />

Tornadoes are much<br />

smaller than hurricanes<br />

and they usually only<br />

last a few minutes,<br />

but they are<br />

very strong!<br />

Measuring the Win<br />

A British man called Francis Beaufort found a way<br />

to record the strength of the wind. This is called the<br />

Beaufort scale.<br />

0<br />

1<br />

~a:-~ :<br />

2 ~~4f<br />

3<br />

calm<br />

= 0 kph<br />

light air<br />

= 3 kph<br />

light breeze<br />

-tif

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