The Track Of 2013'S Ef5 Tornado In Moore, Okla., Is Overlaid On Zip Codes In Cook County, Ill. (Photo: Swiss Re)
Track of 2013’s EF5 tornado in Moore, Okla., is overlaid on ZIP codes in Cook County, Ill. (Photo: Swiss Re)

Swiss Re has just issued a new report that could leave many who reside in large U.S. cities sleepless. It asks and answers the gritty question: What if a tornado hit a major U.S. city?

The report notes that a single violent tornado could cause as much as $20 billion in property damage — and countless casualties and deaths — if it hit a big city such as downtown Chicago. In addition to deaths and injuries, there would be thousands of people made homeless, tens of thousands would lose power, and hundreds of thousands would be unable to get to work. Sounds like an earthquake or hurricane doesn’t it?

Fierce tornado outbreaks have dogged the U.S. in recent years, with high death tolls and damage from twisters in and around smaller cities such as Joplin, Mo., Tuscaloosa, Ala., and Moore, Okla. These of course are relatively small towns. Overall, the annual average loss from severe thunderstorms and the tornadoes they produce is about $5.5 billion, Swiss Re reports.

Swiss Re found that densely populated and developed Cook County, Ill., which includes the city of Chicago, has the greatest potential exposure to a violent and long-track tornado. If the same EF5 tornado that hit Moore, Okla., in 2013 hit Chicago, tens of billions of dollars’ worth of property would lie in the tornado’s path.

Damage estimates for the tornado would be in excess of $20 billion. An estimated 112,000 people live within the tornado damage swath, of which many would be injured or killed, despite improvements in tornado warnings from the National Weather Service, a branch of the National Oceanic and Atmospheric Administration (NOAA).

The report is an interesting read and available on the Swiss Re website using the link below.