Al Roker of the "Today" show recently did a PSA on how to think ahead for a disaster. The beloved weatherman has covered countless hurricanes, tornadoes and other natural disasters and has seen the devastation first hand. Teaming up with the Federal Emergency Management Agency (FEMA), his 30-second humorous public service announcement message was: Plan ahead before the next storm hits. Do you know what types of disasters impact your community? Do you know first aid? Could you go a week without power? And what would you grab with a 30-minute evacuation notice? Most people don't know. It's very much about denial, says John H. Clouse, a disaster-preparedness consultant and founder of The Joseph Group in Owensboro, Ky. He says only when people get a brief taste of disaster, survive a crisis, or experience a narrow miss do they become engaged in the process of disaster planning. "Even though people think there will be fire, hurricanes and earthquakes, they think the impact to them will be not that severe," says Robert Meyer, professor of marketing at the Wharton School of the University of Pennsylvania and co-director for the Center for Risk Management and Decision Processes Center. People have a very difficult time estimating a loss, or they severely underestimate tail impact or tail severity, meaning the total financial loss. If you're an insurance agent thinking about pricing a policy, what you care about is not the size of the average loss but the size of the potential actual total loss. That's what people have a hard time imagining, explains Meyer. For instance, Mayor Ed Lee of San Francisco is having a difficult time getting residents to voluntarily retrofit their building structures to withstand earthquakes. While it's an expensive endeavor, the real reason home and business owners balk is they can't quite imagine the severity of loss in an earthquake, according to Meyer's theory. Here's more on how Californians have their heads buried in the sand.