Special Winds

What Is a Hurricane?

Hurricanes are gigantic cyclones, which can cause a lot of damage due to their size. They can have a diameter of more than 500 km. The centre of the hurricane, the eye, where it is almost still, has a diameter between 15 and 30 km.

The hurricane can be made out on satellite pictures, and therefore it is possible to send out gale warnings in time. The actual cyclones, which always cause a lot of damage, are followed by torrential rainfalls.

What Is a Tornado?

A tornado is a hose-shaped cyclone. It is smaller than the hurricane, but still has devastating effects. Usually it occurs in conjunction with thunderstorms, like the hurricane, especially in the Midwest of the United States. Its diameter is between 10 and 100 metres. The speed of the originating up-currents in the hose reaches up to 600 km/h.

Origin:

1. Two weather elements have to collide (cold and hot air).
   Cold front <- --> warm front
2. The warm air glides up on the cold air.

Normally, the warm air rises like a balloon, cools down during that ascension and forms water droplets, which fall to the ground as rain. If a crosswind occurs in addition to these extreme differences between cold and warm air, which deflects the ascending warm air to the side, this warm air starts to rotate around its own axis with high speed. The vortex gets faster and faster and narrower and narrower – like a skater who rotates faster, when he/she puts his/her arms to his/her side.