A tornado is a violently rotating column of air extending from the base of a thunderstorm down to the ground. Tornadoes are capable of completely destroying well-made structures, uprooting trees and hurling objects through the air like deadly missiles. Tornadoes can occur at any time of day or night and at any time of the year. Although tornadoes are most common in the Central Plains and southeastern United States, they have been reported in all 50 states. This website is designed to teach you how to stay safe in a tornado. If you know what to do before, during, and after a tornado you can increase your chances of survival. You'll also find links to research, past events and other topics of interest. Download our free Thunderstorms, Lightning and Tornado booklet for more information. If you, or someone you know, have been a victim of a tornado or severe thunbderstorm, please share your story so we can prevent others from becoming a victim. When you write, please note that NWS has permission to use your story and, if possible, let us know the town and state you were in and the year the event took place. Read stories of real survivors.
A thunderstorm is considered severe if it produces hail at least 1 inch in diameter or has wind gusts of at least 58 miles per hour. Every thunderstorm produces lightning, which kills more people some years than tornadoes or hurricanes. Heavy rain from thunderstorms can cause flash flooding. High winds can damage homes and blow down trees and utility poles, causing widespread power outages. Every year people are killed or seriously injured because they didn't hear or ignored severe thunderstorms warnings. The information in this section, combined with timely watches and warnings about severe weather, could save your life.
Lightning and Flood Threats
While much of the focus during severe weather is on tornadoes, wind and hail, there are actually more deaths caused each year by flooding and lightning, which are also commonly associated with severe weather. If you hear thunder or see lightning, head inside immediately! When Thunder Roars Go Indoors! Heavy rainfall from thunderstorms can quickly cause rivers and streams to overrun their banks and cause street flooding in cities. Remember, if you encounter a flooded roadway, do NOT drive or walk into it. Turn Around Don’t Drown! Visit weather.gov/lightningsafety and weather.gov/floodsafety for more safety tips and information.