MARY LOUISE KELLY, host:
On Tuesday evening, a powerful tornado was heading toward Piedmont, Oklahoma. The news staff at TV station KFOR was telling people there, get ready.
Unidentified Man #1: Look at the size of this thing, Mike.
Unidentified Man #2: Piedmont, get below ground. Piedmont, get below ground or get out of the way. You're running out of time. You're down to like a minute or two. Get out of the way.
KELLY: Despite warnings like that, several people in Piedmont were killed. So far this year, the nation's death toll for tornadoes is about 500. NPR's Jon Hamilton reports there would be fewer deaths if everyone knew what to do as a twister approaches.
JON HAMILTON: People who study tornadoes tend to have a detailed plan for surviving one. Harold Brooks is a researcher at the National Severe Storms Laboratory in Norman, Oklahoma.
Mr. HAROLD BROOKS (Research Meteorologist, National Severe Storms Laboratory): The walk-in closet on our master bedroom suite is six inches of reinforced concrete with a steel door on it and a six inch cap on top of the closet. And we can get in there with children, pets, valuables and things like that.
HAMILTON: Brooks says a shelter like that protects you from things like a two-by-four ripped from a wall and propelled by winds that can exceed 200 miles an hour.
Mr. BROOKS: It's like getting hit by a baseball bat. Bricks that fly through the air are also causes of major injuries. And so it's all of those things as structures start to fall apart and produce lots of six inch to two-foot-long missiles that can hit you or impale you, and that's pretty much how people get hurt.
HAMILTON: Brooks says people who don't have a shelter can still do a lot to protect themselves.
Mr. BROOKS: Get low, put walls between you and a small room, if possible, a closet, an interior bathroom, a small hallway. Once you get in there, something like a bicycle helmet or a football helmet on your head, and that can help dramatically improve your chances of surviving without significant injury.
HAMILTON: But a lot of people don't do any of that. Instead, they do things like opening all the windows, thinking it will prevent their house from exploding in the low-pressure eye of a tornado.
Brooks says that's a myth, and open windows can cause another problem.
Mr. BROOKS: Because once the wind gets inside of your house, it essentially can start to lift the roof up off the house.
HAMILTON: People in cars make mistakes too. Robin Tanamachi is a researcher at the Center for Analysis and Prediction of Storms in Norman. She spent the past eight years chasing severe storms in radar trucks.
Ms. ROBIN TANAMACHI (Researcher, Center for Analysis and Prediction of Storms, Norman, Oklahoma): One thing that we've observed, quite frequently, is that people will try to shelter under highway overpasses. And that's a tremendously bad idea.
HAMILTON: It's also become very popular, thanks to a video from 1991 - that shows a news crew hiding under an overpass as a tornado goes by. That strategy doesn't usually work. Since then, several people who've tried it have died. And research shows that an overpass can act like a wind tunnel and actually make you more vulnerable.
The best thing to do if you're in a car is drive to a building. Fast food restaurants are good because they usually have a walk-in cooler that will work as a shelter.
Tanamachi says driving away from a tornado can also save your life. But you shouldn't try to outrun the twister, as many people do. Instead, pick an escape route that takes you 90 degrees from the storm's path. And Tanamachi says drivers need to plan for the worst.
Ms. TANAMACHI: If you find yourself in a vehicle and unable to escape from the tornado, abandon the vehicle and try to get into a nearby ditch or a culvert. Protect your head and face and don't look at the tornado as it goes by, because you may be impacted by debris.
HAMILTON: For scientists like Tanamachi, these safety steps aren't just theoretical. After all, she lives in Norman, Oklahoma, which is in the area known as Tornado Alley.
On Tuesday evening, Tanamachi was taking part in a workshop at the National Weather Center in Norman when the twisters appeared.
Ms. TANAMACHI: They actually did issue a tornado warning that affected our building and we all had to evacuate down into the tornado shelter for awhile.
HAMILTON: Until the tornado subsided, a few miles away.
Jon Hamilton, NPR News.