Rising temperatures are not just a concern for the future. Dangerously hot weather is already occurring more frequently in the Midwest than it did 60 years ago.

The report, Heat in the Heartland: 60 Years of Warming in the Midwest, presents an original analysis of weather data for five major urban areas — Chicago, Cincinnati, Detroit, Minneapolis, and St. Louis — as well as five smaller nearby cities.

The results from the analysis are clear: Hot summer weather and heat waves have been increasing in cities in the nation’s heartland over the last six decades on average. The report documents this trend, explores its health implications, and looks at what the largest cities are doing to adapt to these changes and protect their residents.