The year before Katrina hit the Gulf Coast, devastating the city of New Orleans, many people had sounded the warning about the iconic city’s levees — including Glenn.

RELATED: This Day in History: Katrina Slams the Gulf Coast

In this #ThrowBeck audio file, Glenn begins with a chilling question.

“When you think of the city in America that is most in jeopardy, what city comes to mind? If you’re thinking about manmade disasters, most likely you think of New York City, that that’s the city that is the number one target. When you’re talking about natural disasters, what city is the number one target? What one do you think has the chance of just killing everybody, from a natural disaster. Any thoughts?” Glenn asked.

Back in 2004, most people would have answered San Franscisco — but they would have been wrong. Based on research from 2002, Glenn outlined the scenario that would come true just one year later.

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