1991-2020 Degrees Fahrenheit 1 29.5 30.5 -1.0 42 36 1979 2006 2014 2017 normal 2 31.4 32.2 -0.8 41 37 1984 1992 2014 2017 normal 1967,1976 3 36.2 36.3 -0.1 49 29 1977 2002 2015 2017 normal 4 41.8 41.6 0.2 51 27 1977 2002 2015 2017 normal 5 47.8 47.2 0.6 57 21 1977 2022 2015 2017 top-third 6 52.0 52.4 -0.4 43 35 1977 2022 2014 2017 normal 7 56.1 56.3 -0.2 50 27 1977 1955 2015 2017 normal 8 58.5 58.7 -0.2 46 31 1977 1955 2015 2017 normal 2015 9 59.2 59.5 -0.3 47 30 1977 2002,2013 2014 2017 normal 1950 10 59.1 59.2 -0.1 50 27 1962 2002,2013 2015 2017 normal 1953,2015 11 58.2 57.9 0.3 56 21 1962 2013 2015 2017 top-third 1987 12 57.0 56.1 0.9 65 12 1979 2013 2016 2017 top-third 18 56.2 54.8 1.4 70 7 1979 2013 2016 2017 top-tenth 1992 24 57.7 56.0 1.7 74 2 1962 2013 2017 2013 top-tenth 36 57.3 56.0 1.3 73 2 1963 2013 2017 2013 top-tenth 48 56.7 56.0 0.7 67 7 1962 2002 2017 2014 top-tenth 2020 60 56.2 56.0 0.2 53 20 1963 2003 2012 2017 top-third 2023