Tornadoes can occur just about anywhere, but in the United States they generally occur in the central states. Meteorologists use Doppler radar to track thunderstorms that could spawn tornadoes. Doppler radar is an important tool because it can detect rotating winds within the thunderstorms.

To learn more about how tornadoes form:

1. Go to the Twisters WWW Sheet and print it.

2. Visit both of these Web sites. Then complete the WWW Sheet.
    The Nuts and Bolts of a Whirlwind
    Tornadoes...Nature's Most Violent Storms