Illinois, Average Temperature Rankings, July 2017 1901-2000 Degrees Fahrenheit 1 76.1 75.6 0.5 84 45 2009,2014 1936 2016 2012 normal 1940,1969 2 74.4 73.5 0.9 92 37 1915,1958 1934 2015 2016 top-third 1923,1941,1964,1995,2021 3 70.2 69.7 0.5 77 52 1924 1934 2014 2016 normal 1970,2001 4 66.8 65.2 1.6 104 25 1907 1934 2016 2012 top-third 1930,1998 5 62.1 60.1 2.0 116 13 1960 2012 2015 2016 top-tenth 6 58.6 55.0 3.6 124 5 1947 2012 2016 2012 top-tenth 7 54.8 50.7 4.1 126 3 1912 2012 2016 2012 top-tenth 8 51.6 48.1 3.5 124 4 1904 2012 2015 2016 top-tenth 9 51.2 47.2 4.0 126 2 1904 2012 2016 2016 top-tenth 2016 10 52.1 48.0 4.1 126 2 1904 2012 2016 2012 top-tenth 11 53.8 49.7 4.1 126 2 1904 2012 2016 2012 top-tenth 12 55.6 51.6 4.0 126 2 1904 2012 2016 2012 top-tenth 18 56.3 52.7 3.6 126 2 1918 2012 2016 2012 top-tenth 24 55.3 51.6 3.7 126 1 1905 2017 2016 2017 highest 36 53.8 51.6 2.2 123 3 1979 2018 2016 2012 top-tenth 2012 48 52.7 51.6 1.1 105 20 1905,1980 2019 2016 2013 top-third 1922,2009 60 52.5 51.6 0.9 98 26 1906 2020 2015 2016 top-third 1923,1933,1992,2000,2014