In "The Wizard of Oz," as a twister quickly approaches, Dorothy, too late to join her family in the storm cellar, seeks shelter in her house and is knocked out by a window frame. She definitely did not pick the safest place to wait out a tornado.
If a tornado strikes and you're in a house, apartment, hospital, or other large building, go to a basement, cellar or the lowest level in the building. If there is no basement, go to the most interior room on the lowest level away from windows and doors, like a closet or hallway. (An interior stairwell can work too). Get under a table, and use your arms to protect your head and neck. Or cover yourself with a mattress or blankets.
If you're in a mobile home, leave immediately and go to the lowest floor of the nearest sturdy building. Mobile homes are extremely dangerous places -- most tornado-related deaths occur in and around them. If you're outside or in your car with no shelter in sight, duck into a ditch or depression in the ground, and cover your head and neck. Don't seek shelter under a bridge or overpass.
Once you've headed to your shelter, stay inside and protect yourself until you know for sure that the storm is over. Listen to the radio to get updated information about the weather. Whatever you do, don't leave until you've received official notice that the tornado has passed. While in the shelter, always use battery-powered equipment rather than electronic tools. Using electrical equipment such as grills or generators could put you at for risk carbon monoxide poisoning.
Once you're sure the storm has passed, use caution when entering a possibly damaged structure, and remember to make use of those sturdy shoes, long sleeves and gloves that you packed in your emergency kit. Look out for nails and broken glass; avoid contact with power lines that have been knocked down, and report downed power lines to the police and the utility company. If you suspect that damage has been done to your home, cut off the electrical system at the circuit breaker to avoid risk of a fire.
Perhaps most importantly, cooperate with law enforcement and public safety officials. They have the latest news on not only the status of the tornado but also evacuation procedures and safety.