Number of days with minimum temperatures equal to or exceeding 70°F at 5 large Midwestern cities
Five-year running mean of the number of days with minimum temperatures equal to or exceeding 70°F at 5 large Midwestern cities: Chicago, IL (KMDW); Minneapolis, MN (KMSP); St Louis, MO (KSTL); Cleveland, OH (KCLE); and Columbus, OH (KCMK). For KCLE, temperature data started in 1938. All of the large cities exhibit statistically significant upward trends for the period of 1950-2009. Figure courtesy of Illinois State Water Survey.
Midwest, Observed, Temperature