Thunderstorms, hail and thousands of power outages in the Chicago area grounded flights at O'Hare and midway international airports and delayed an NFL game between the Baltimore Ravens and Chicago Bears at Soldier Field.

At least 12 counties in Indiana reported tornado damage, with states of emergency declared in Howard County, home to the towns of Kokomo, Russiaville and Greentown. Severe damage was also reported in Lafayette, Washington and Lebanon cities. One tornado in Logansport caused gas leaks that prompted several complexes to be evacuated.

Eight Kentucky counties reported tornado touchdowns. The Great Lakes were also affected, primarily by winds that left 253,000 customers without electricity in Michigan. Similar winds as fast as 70 mph were recorded in Missouri, Ohio and Wisconsin.

While it is too early to tell the full scope of the losses, Loretta Worters, spokesperson for the Insurance Information Institute, expects that “hundreds of homes and businesses were damaged or destroyed.”

“Claims adjusters have already begun to help policyholders file claims,” says Jim Whittle, chief claims counsel for the American Insurance Association. “AIA's member companies have begun communicating with policyholders through a variety of channels, including Facebook and Twitter.”

Until Sunday, economic and insured losses from severe weather in 2013—the quietest U.S. tornado year since 1988—were slightly below the 10-year average, records the Storm Prediction Center. U.S. thunderstorms cost $14.9 billion insured losses in 2012, reports Munich Re. The United States experiences more tornadoes than any other country worldwide.