Tornado – Killing Beauty

A tornado is defined as a violently rotating column of air extending from a thunderstorm to the ground. The most violent tornadoes are capable of tremendous destruction with wind speeds of 250 mph or more. Damage paths can be in excess of one mile wide and 50 miles long. Once a tornado in Broken Bow, Oklahoma, carried a motel sign 30 miles.

Waterspout

Waterspouts are weak tornadoes that form over warm water.

Waterspouts are most common along the Gulf Coast and southeastern states. In the western United States, they occur with cold late fall or late winter storms, during a time when you least expect tornado development.

Waterspouts occasionally move inland becoming tornadoes causing damage and injuries.

How Do Tornadoes Form?

Before thunderstorms develop, a change in wind direction and an increase in wind speed with increasing height creates an invisible, horizontal spinning effect in the lower atmosphere.	Rising air within the thunderstorm updraft tilts the rotating air from horizontal to vertical.	An area of rotation, 2-6 miles wide, now extends through much of the storm. Most strong and violent tornadoes form within this area of strong rotation.

Tornadoes Take Many Shapes and Sizes

Weak Tornadoes	Strong Tornadoes	Violent Tornadoes
69% of all tornadoes 5% of tornado deaths Lifetime 1-10 minutes Wind less than 110 mph	29% of all tornadoes 30% of all tornado deaths May last 20 minutes or longer Winds 110-205 mph	Only 2% of all tornadoes 70% of all tornado deaths Lifetime can exceed 1 hour Wind Speed more than 205 mph

Tornadoes have been reported in Great Britain, India, Argentina, but most tornadoes occur in the United States. In India, though Tornado is not a common feature but parts of extreme eastern India have experienced twisters. One of the most disastrous Tornadoes that India experienced was in 1902 before India, Pakistan, and Bangladesh separation. It was reported in the New York Times that more than 400 people were killed.

Check this link to read the news item in The New York Times

Have a look at this slide show that contains rare pictures of Tornado.

Source : The National Geographic