Return to Learn the Basics

Tornadoes

A tornado is a violent whirlwind - a rotating funnel of air that extends from a cloud to the ground. Tornadoes can travel for many miles at speeds of 250 miles per hour or more. These storms change direction without warning, randomly destroying homes and power lines, uprooting trees, and even hurling large objects - such as automobiles - over long distances.

Tornadoes can occur in any state at any time of the year. Nationally, an average of 800 tornadoes are sighted each year, causing about 80 deaths and more than 1,500 injuries.

A tornado watch is issued when weather conditions favor the formation of tornadoes, for example, during a severe thunderstorm.

A tornado warning is issued when a tornado funnel is sighted or indicated by weather radar.

The following weather signs may mean that a tornado is approaching:

• A dark or green-colored sky.
• A large, dark, low-lying cloud.
• Large hail.
• A loud roar that sounds like a freight train.

Immediately take shelter in one of the following locations:

• Bathroom
• Closet
• Hallway
• Under a table
• Under the door frame

A study of injuries after a tornado in Marion, Illinois, showed that 50% of the tornado-related injuries were suffered during rescue attempts, cleanup, and other post-tornado activites. Because tornadoes often damage power lines, gas lines, or electrical systems, there is a risk of fire, electrocution, or an explosion.

Do not use matches, lighters, or appliances, or operate light switches until you are sure there are no gas leaks.

Return to Learn the Basics