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Tornados

"Dorothy lived with her Aunt Em and Uncle Henry on a small farm in Kansas. Their tiny house stood alone on a large, flat prairie.   Dorothy had only one friend, her dog Toto. He was a small black dog who loved to jump and play.   One day while Dorothy and Toto were playing, they heard the awful sound of a storm. The wind roared and the dust blew smoky circles in the air. Dorothy was frightened. Uncle Henry stopped working and shouted,   ‘There's a cyclone coming, run for the cellar!' "
The Wizard of Oz
By: Frank Baum (1939).
Tornados remain a frightening fact of life for those of us in the Midwest. These powerful acts of nature can wreak havoc on everything in its path of destruction. Tornado, twister, funnel, and cyclone: all are synonyms for the awesome force, which has intrigued and puzzled scientists for years.
A tornado is the most violent of all storms. It is a violent rotating column of air extending from within a thundercloud or a developing thundercloud down to ground level. Tornados can vary in diameter from tens of meters to about two kilometers with an average diameter of approximately 50 meters. In the northern hemisphere, winds of the tornado generally blow counterclockwise around a center of extremely low atmospheric pressure.   In the majority of tornadoes that occur in the southern hemisphere, winds blow clockwise.   The peak wind speeds can range from 75 mph to almost 300 mph. Some of the more powerful tornados can lift cattle, cars, and even mobile homes.   A tornado becomes visible when a condensation funnel made of water vapor forms in very low pressures. It also becomes visible when the tornado lifts dust, dirt, and debris upward from the ground.
Most tornados are just small, intense cyclones. The term cyclone comes from the Greek word circle. Sometimes, in very rare occasions, the winds whirl in the direction opposite of a cyclone. For the most part, tornados have damage path less than 500 meters wide, move at less then 35 miles per hour,...