Tornado

The National Weather Service alerts the public to severe weather hazards by issuing watches and warnings that are broadcast on National Oceanic and Atmospheric Administration (NOAA) weather radio, television, and commercial radio. Meteorologists issue a tornado watch when weather conditions are favorable for the development of tornadoes and severe thunderstorms. Watches are often issued hours before severe weather develops and generally cover many counties or even several states. A tornado warning means that a tornado is occurring or is imminent. A warning is issued if a tornado has touched down, if a funnel cloud is present, or if Doppler radar indicates the presence of strong rotation in a thunderstorm updraft. The area covered by a warning is much smaller than a watch, usually only a county or two, or a portion of a county.

During a tornado warning, people should seek shelter immediately in a basement or in the interior portion of a building (a closet, interior hallway, or bathroom). Mobile homes and cars have a tendency to roll in high winds and should therefore be abandoned. Structures with large, free-span roofs, such as auditoriums, gymnasiums, and supermarkets, are subject to collapse and should also be avoided. If caught outside, a person should lie flat in a ditch and cover his or her head for protection from flying debris.