1991-2020 Degrees Fahrenheit 1 47.8 45.4 2.4 85 9 1983 2021 1993 1977 top-tenth 2 51.3 49.3 2.0 83 11 1932 2021 1993 1981 top-third 3 56.1 54.7 1.4 81 13 1932 2021 1993 1981 top-third 2012 4 60.6 59.9 0.7 75 19 1932 2021 1993 1981 top-third 1946,2005 5 64.9 64.4 0.5 73 21 1976 2021 1993 1977 top-third 2014,2022 6 68.1 67.5 0.6 74 20 1976 2021 1993 1977 top-third 1965 7 70.4 69.5 0.9 80 14 1976 2021 1993 1977 top-third 8 70.5 70.1 0.4 76 17 1976 1998 1993 1977 top-third 1999,2015 9 69.8 69.6 0.2 74 19 1976 2022 1993 1977 top-third 1946,2014 10 68.6 68.3 0.3 79 14 1976 2011 1993 1934 top-third 2000 11 66.6 66.6 0.0 74 19 1976 2011 1993 1954 top-third 12 64.7 64.8 -0.1 72 19 1976 2017 1993 1954 top-third 18 65.2 65.6 -0.4 64 27 1976 2017 1993 1955 top-third 1950,1951,1955,2014 24 63.9 64.7 -0.8 54 35 1976 2017 1993 1956 normal 1946 36 63.5 64.7 -1.2 47 40 1976 2018 1993 1991 normal 1934,1946,1947 48 63.4 64.6 -1.2 42 43 1976 2019,2020 1993 1965 normal 1934,1935,1949,1950 60 63.5 64.6 -1.1 47 36 1976 2020 1993 1958 normal 1937,1958,1995