1991-2020 Degrees Fahrenheit 1 79.8 79.5 0.3 49 26 1997 1952 2017 2018 normal 2 78.5 76.1 2.4 71 4 1997 1998 2018 2011 top-tenth 2011 3 74.2 72.2 2.0 71 4 1997 2011 2018 2015 top-tenth 1977 4 69.9 68.6 1.3 67 8 1971,2013 2012 2018 2016 top-third 5 67.2 65.1 2.1 72 3 1960,1971 2012 2018 2017 top-tenth 6 64.2 62.2 2.0 70 4 1978 2017 2018 2017 top-tenth 7 62.4 60.5 1.9 69 5 1978 2017 2018 2017 top-tenth 1950 8 61.3 59.9 1.4 65 8 1970 2017 2018 2017 top-third 9 62.2 60.6 1.6 70 3 1977 2017 2018 2017 top-tenth 1950,1957,2012,2020,2022 10 64.2 62.1 2.1 71 2 1968 2017 2018 2017 top-tenth 11 65.8 63.9 1.9 71 2 1968 2017 2018 2017 top-tenth 2020 12 67.1 65.4 1.7 70 3 1968 2017 2018 2017 top-tenth 18 65.8 64.4 1.4 69 3 1970 2017 2018 2018 top-tenth 1991,2018 24 66.6 65.4 1.2 67 4 1969 2017 2016 2018 top-tenth 2021 36 67.2 65.3 1.9 68 1 1970 2019 2018 2019 highest 48 67.1 65.3 1.8 65 2 1971 2020 2018 2019 top-tenth 60 66.7 65.3 1.4 62 3 1970 2020 2018 2019 top-tenth