Tornado Journal Entry

Killer Tornadoes Rip the South (February 6, 2008)

Violent storms spawned deadly tornadoes that ripped across the South this week. The storms and twisters left a trail of destruction across parts of Tennessee, Arkansas, Kentucky, and Alabama. More than fifty people were killed and hundreds of homes were destroyed.

Tennessee was hit especially hard. One twister slammed into a natural gas transmission station, triggering a huge fire. Flames shot more than 400 feet into the night sky.

Twisters don't usually form in the winter because they need a big supply of warm, moist air near the ground. Still, they can and do strike at any time if conditions are right. They often result from collisions of two huge air masses. In the United States, cold, dry air from Canada or the Rockies slams into warm, humid air rising from the Gulf of Mexico. The colliding air masses can create a funnel cloud of violent winds surrounding an area of extremely low barometric pressure. The cloud becomes a tornado when it touches the ground.

The United States gets struck with more tornadoes than anywhere else on the planet. Most occur in the spring and summer months. They are most common in the central and southern parts of the country. About 800 tornadoes touch down in the U.S. every year, killing an average of 80 people and injuring 1,500 others. The most violent twisters have wind speeds of over 250 mph (400 km/h).