A tornado is a violently rotating column of air that extends from a thunderstorm to the ground and is often - although not always - visible as a funnel cloud. Lightening and hail are common in thunderstorms that produce tomadoes. Tomadoes cause extensive damage to structures and disrupt transportation, power, water, gas, communications, and other services in its direct path and in neighbouring areas. Related thunderstorms can cause heavy rains, flash flooding, and hail.
About 1,200 tornadoes hit the United States every year and every state is at risk. Most tornadoes in the United States occur east of the Rocky Mountains with concentrations in the central and southem plains, the Gulf Coast and Florida.
Tornadoes can strike in any season, but occur most often in the spring and summer months. They can occur at all hours of the day and night, but are most likely to occur between 3p.m. and 9 p.m.

1. What is a tomado?

2. What is common in thunderstorms that produce tornadoes?

3. What can related thunderstorms cause?

4. How many tornadoes hit the United States every year?

5. Which seasons can tomadoes strike?