TORNADO FACTS

 Tornadoes are among the most violent storms on Earth. Understanding what they are, how they are rated, and what to do when one threatens can help families make better safety decisions. 

 A tornado is a narrow, violently rotating column of air that develops from a thunderstorm and extends down to the ground. It forms when changing wind speed and direction help create rotation inside a storm, and a strong updraft tilts and stretches that rotation vertically until it can tighten into a powerful spinning circulation. The visible funnel is usually made of condensed water droplets, dust, and debris, but the damaging winds can extend beyond what you can actually see. Tornadoes vary greatly in size, speed, strength, and duration, but all can produce dangerous winds, flying debris, and sudden structural damage. 

Tornadoes have been reported in all 50 states. They are most common in parts of the Central Plains and southeastern United States, but no state is completely immune.

There is no single nationwide “tornado season.” Tornadoes can occur during any month of the year and at any time of day or night. Different parts of the country experience their greatest tornado risk at different times of the year.

Tornadoes can occur after dark when people are sleeping and may not see the storm approaching. Families should have more than one dependable way to receive weather warnings, including Wireless Emergency Alerts and a NOAA Weather Radio.

The National Severe Storms Laboratory reports that approximately 1,200 tornadoes occur in the United States during an average year. The exact number varies considerably from year to year.

A tornado may be difficult to see because wind itself is invisible. Some tornadoes become visible because of condensation, dust and debris, while others may be hidden by heavy rain or darkness. Never wait until you can actually see a tornado before taking a Tornado Warning seriously.

According to the National Severe Storms Laboratory, tornado movement can range from nearly stationary to more than 60 mph. A typical tornado moves roughly 10 to 20 mph.

Because speed and direction can change, trying to judge a tornado's movement simply by watching it is dangerous.

The National Severe Storms Laboratory says the time a tornado remains on the ground can range from an instant to several hours, with an average of approximately five minutes. Even a short-lived tornado can cause serious damage.

Tornado winds can propel pieces of wood, metal, glass and other objects at dangerous speeds. This is one reason tornado safety guidance emphasizes getting away from windows and protecting your head and body.

Conditions are favorable for tornadoes in or near the watch area. Know where you will take shelter and be ready to act quickly.

A tornado has been observed or indicated by weather radar and danger is imminent. Go to your safest available location immediately. Do not wait to see or hear a tornado before taking shelter.

A Tornado Warning can sometimes provide only a short amount of time to reach safety. Your safest location should be decided before severe weather arrives.

Do not seek shelter beneath a highway overpass. Wind speeds can be dangerous beneath and around the structure, and flying debris can cause serious injury.

The National Weather Service recommends moving from a mobile home to a substantial building or designated storm shelter when tornadoes threaten. A vehicle should not be considered a tornado shelter.

National Weather Service guidance recommends going to a basement or a small interior room on the lowest floor of a sturdy building, away from windows. Protect your head and neck from flying or falling debris. An interior bathroom, closet or hallway may be your best available option when a purpose-built shelter or safe room is not available.

An interior room can be an important place of refuge when no better protection is available. However, a purpose-built storm shelter or safe room is specifically engineered to provide a higher level of protection from extreme winds and wind-borne debris.

Although the Great Plains are famous for tornadoes, the southeastern United States also experiences significant tornado activity. Tennessee and surrounding states can experience tornadoes during spring as well as during fall and winter severe-weather episodes.

You cannot control whether a tornado forms. You can control whether your family knows where to go, how quickly everyone can get there, and whether you have reliable ways to receive a warning. Being prepared before the warning arrives can make a critical difference.