1991-2020 Degrees Fahrenheit 1 73.0 74.4 -1.4 22 54 1955 2010 1965 1964 bottom-third 2 69.5 70.6 -1.1 29 47 1992 2018 1963 1965 normal 1999 3 64.3 66.6 -2.3 8 68 1961,1997 2010 1961 1965 bottom-tenth 1973,1979,1989 4 60.4 62.2 -1.8 18 58 1960 2012 1962 1965 bottom-third 1962,1967,1989 5 55.7 58.0 -2.3 12 64 1958 2012 1961 1965 bottom-third 1950 6 51.9 54.8 -2.9 6 70 1958 2012 1963 1965 bottom-tenth 1963 7 50.5 52.9 -2.4 13 62 1978 2012 1964 1965 bottom-third 2003 8 50.4 52.4 -2.0 18 57 1958,1963,1978 2012 1964 1965 bottom-third 1968 9 51.0 53.2 -2.2 12 63 1958 2012 1963 1965 bottom-third 1968,1969 10 53.1 54.9 -1.8 19 56 1958 2017 1964 1965 bottom-third 1989,1993 11 55.2 56.9 -1.7 19 56 1958,1977 2017 1964 1965 bottom-third 1975,1980 12 56.9 58.7 -1.8 17 58 1977 2017 1964 1965 bottom-third 1975,1979,1996,2001 18 55.7 57.4 -1.7 19 56 1961 1991,2012,2017 1964 1965 bottom-third 1951,1956,1984 24 57.1 58.6 -1.5 20 54 1978 2017 1965 1960 bottom-third 1956 36 56.9 58.6 -1.7 12 61 1979 2018 1965 1961 bottom-third 1958,1961,1982 48 56.6 58.6 -2.0 6 66 1980 2020 1964 1965 bottom-tenth 60 56.7 58.5 -1.8 6 65 1964 2020 1965 1963 bottom-tenth 1962,1963