1991-2020 Degrees Fahrenheit 1 73.0 72.8 0.2 44 31 1954 1962 1981 1977 normal 2 67.2 68.6 -1.4 16 59 1997 1955 1976 1981 bottom-third 2020 3 64.7 65.0 -0.3 45 30 1971 2012 1981 1977 normal 1952,1970,1990 4 61.5 61.5 0.0 46 29 1971 2012 1981 1977 normal 1950,1952,1965,2001 5 57.9 58.8 -0.9 30 44 1978 2017 1981 1976 normal 2008 6 55.9 57.3 -1.4 23 51 1978 2017 1981 1976 bottom-third 1951,2004,2011 7 55.8 57.1 -1.3 21 52 1977 2017 1981 1980 bottom-third 8 56.7 58.2 -1.5 20 53 1977 2017 1981 1980 bottom-third 1951 9 58.6 60.2 -1.6 18 55 1968 2017 1981 1980 bottom-third 1951 10 60.5 62.3 -1.8 11 62 1968 2017 1978 1981 bottom-third 2014 11 62.5 64.2 -1.7 13 60 1968 2017 1978 1981 bottom-third 1988 12 64.1 65.4 -1.3 20 53 1968 2017 1980 1981 bottom-third 1961,1984 18 61.1 62.7 -1.6 11 61 1970 2017 1980 1981 bottom-third 1993 24 64.3 65.4 -1.1 18 53 1969 2017 1981 1980 bottom-third 1980,1983,1984,1994,1997 36 64.2 65.3 -1.1 11 58 1970 2019 1980 1981 bottom-third 1960,1964,1967 48 64.3 65.3 -1.0 14 53 1971 2020 1981 1977 bottom-third 1963,1965,1973,1983,1984 60 64.2 65.3 -1.1 13 52 1970 2020 1981 1978 bottom-third