What is a tornado? tornado is a violent whirling wind that moves across the ground in a narrow path. A How are Tornadoes formed? Late in the day, when earth’s surface is very warm, convection (The flow of heat through a material, causing hot parts to rise and cooler parts to sink.) can get very strong. This can lead to a tornado. A tornado is a sort of a runaway convection cell. A convection cell is a circular pattern of air rising, air sinking and wind. Tornado Happenings 1.When the updraft in a convection cell is really strong, the air rushes in from all sides at high speeds. 2. Air curves into a spin. This lowers the pressure even more. Air rushes in even faster, and the pressure gets even lower, and so on. Like a skater who pulls her arms in close to her sides. The tornado spins faster and faster. 3. As the tornado gets stronger, a funnel forms that can destroy anything in it’s path. The center of the tornado can reach speeds of 500 kilometers per hour (about 300 miles per hour) or more. Where Do Tornadoes Happen? Tornadoes happen where dry, cold air masses mix with warm, moist air masses. tornadoes occur in the United States than in any other country, especially in the area known as TORNADO ALLEY. More A Famous Tornado Grand Island, Nebraska June 3, 1980 On June 3, 1980, a series of tornadoes devastated the city of Grand Island, Nebraska. Seven tornadoes hit within a three hour period. The storm did massive damage and closed the city down for three days.