Grade 7 | Science | Storms - Tornado, Winds, Storms and Cyclones, Olympiad, CBSE, ICSE, SOF, ITO
A tornado is a violent rotating column of air extending from a thunderstorm to the ground. The most violent tornadoes are capable of tremendous destruction with wind speeds of up to 300 mph. They can destroy large buildings, uproot trees and is capable of hurling vehicles hundreds of yards away. They can also drive straw into trees.
Most tornadoes form from thunderstorms. It needs warm, moist air and cool air mixing with dry air. When these two air masses meet, they create instability in the atmosphere. 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 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.