Tornado Season Returns
09 April 2012
Several tornadoes hit the Dallas-Fort Worth area of Texas last week, causing heavy damage but no deaths
BARBARA KLEIN: This is SCIENCE IN THE NEWS in VOA Special English. I'm Barbara Klein.
BOB DOUGHTY: And I'm Bob Doughty. This week, we explore the science of tornadoes. These violent storms strike in many parts of the world but happen most commonly in the United States.
(MUSIC)
BARBARA KLEIN: Tornado season has begun in the United States.
Last Tuesday a series of storms tore across the Dallas-Fort Worth area in Texas. The tornadoes damaged or destroyed hundreds of homes. Yet no deaths were reported.
On March second, more than forty tornadoes moved through the Ohio and Tennessee Valleys, and the South. Reports say the storms killed at least thirty-nine people in five states.
A tornado is a violently turning tube of air suspended from a thick cloud. It extends from a thunderstorm in the sky down to the ground. The shape is like a funnel: wide at the top, narrower at the bottom.
A funnel cloud touches down in Orchard, Iowa, on June 10, 2008
Tornadoes form when winds blowing in different directions meet in the clouds and begin to turn in circles. Warm air rising from below causes the wind tube to reach toward the ground. Because of their circular movement, these windstorms are also known as twisters.
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