I kept meaning but forgetting to come by and see if other people commented on this lame advice from Click & Clack. Asking Tom & Ray their advice on tornado safety is a little like asking two guys who have lived their lives in South Florida how to handle a car in snow.
Back in 1960s, disaster planners used to advise, in the event of a tornado, opening the windows on one corner of the house to “equalize the pressure.” To demonstrate the folly of this advice, you only need to watch a video of a tornado hitting a house, such as http://www.youtube.com/watch?v=lAPnbzHvIKs . Not only does opening windows not prevent damage, it puts you in danger because it wastes time you should be using to find shelter. They don’t advise opening windows any more.
Direct hits from strong tornados are uncommon, even in Kansas in the heart of tornado alley, but if a tornado comes near your home, the best place to be is underground, not in a car with glass windows in a garage which may be swept away in seconds. And you don’t have time to tie the car down, not that that would reliably work if you did.