Have you ever wandered who in the world would want to be a storm chaser? They chase storms in hopes of finding a tornado! Although tornadoes can occur anywhere in the world; they mostly occur in the United States.
A tornado is a violent rotation of air that reaches the ground. It almost always starts as a funnel cloud. It can do more damage than any other weather related catastrophy. And quess what? We, in Oxford, live in the "Tornado Alley". This means that tornadoes are most likely to happen in these areas.
So, how are tornadoes formed? It is your responsibility to find out.
A tornado begins in a severe thunderstorm called a supercell. A supercell can last longer than a regular thunderstorm. The same property that keeps the storm going also produces most tornadoes. The wind coming into the storm starts to swirl and forms a funnel. The air in the funnel spins faster and faster and creates a very low pressure area which sucks more air (and possibly objects) into it.
The severe thunderstorms which produce tornadoes form where cold dry polar air meets warm moist tropical air. This is most common in a section of the United States called Tornado Alley. Also, the atmosphere needs to be very unstable.
Tornadoes can form any time during the year, but most form in May. But, more severe ones form earlier because the most damge is caused in April. The more north you go, the later the peak tornado season is. This is because it takes longer to warm the northern parts of the plains so tornadoes form later.
Most tornadoes spin cyclonically but a few spin anticyclonically. Because there are records of anticyclonic tornadoes, scientists don't think that the Coriolis Effect causes the rotations.