1901-2000 Degrees Fahrenheit 1 46.6 49.5 -2.9 29 101 1895 2018 1968 1966 bottom-third 1940 2 45.9 48.4 -2.5 27 103 1978 1950 1968 1967 bottom-third 1901 3 45.6 48.4 -2.8 16 113 1978 1932 1964 1968 bottom-third 1981 4 47.5 50.1 -2.6 13 116 1977 1932 1964 1968 bottom-tenth 5 51.0 53.1 -2.1 17 112 1977 1932 1968 1967 bottom-third 1908 6 54.7 56.7 -2.0 13 116 1977 1932 1968 1967 bottom-tenth 7 58.3 59.9 -1.6 13 116 1977 1932 1968 1967 bottom-tenth 8 60.8 62.4 -1.6 13 116 1977 1932 1968 1967 bottom-tenth 9 62.6 64.0 -1.4 12 117 1977 1932,2017 1968 1967 bottom-tenth 1940 10 63.3 64.7 -1.4 10 119 1977 2017 1968 1967 bottom-tenth 11 63.4 64.6 -1.2 11 118 1977 2017 1968 1967 bottom-tenth 1940,1958 12 62.6 63.9 -1.3 9 120 1977 2017 1968 1967 bottom-tenth 1958 18 59.7 61.5 -1.8 5 123 1978 2017 1905 1968 bottom-tenth 24 62.4 63.9 -1.5 3 125 1978 2017 1905 1968 bottom-tenth 1905,1977 36 62.5 63.8 -1.3 2 125 1970 2018 1969 1968 bottom-tenth 48 62.7 63.9 -1.2 2 124 1970 2019,2020 1905 1968 bottom-tenth 1905,1971,1980 60 62.9 63.9 -1.0 4 121 1970 2020 1969 1968 bottom-tenth 1980