1991-2020 Degrees Fahrenheit 1 59.2 63.6 -4.4 4 72 1967 2004 1967 1966 bottom-tenth 2 56.5 58.8 -2.3 15 61 1967 2019 1967 1965 bottom-third 3 52.4 53.6 -1.2 24 50 1967 2012 1967 1964 bottom-third 2018 4 46.8 49.1 -2.3 14 60 1978 2012 1967 1965 bottom-third 1956,1984,1996,2007 5 43.1 46.0 -2.9 11 63 1978 2012 1967 1965 bottom-third 1948,1963,1979,2015 6 42.0 44.7 -2.7 11 62 1978 2012 1967 1966 bottom-third 1958,1982,2014 7 41.9 45.0 -3.1 9 63 1978 2012 1963 1967 bottom-third 1977 8 43.5 46.5 -3.0 6 66 1978 2012 1963 1967 bottom-tenth 2003 9 45.9 49.0 -3.1 5 67 1978 2012 1963 1967 bottom-tenth 1961 10 48.6 51.7 -3.1 3 69 1978 2012 1963 1967 bottom-tenth 1970,1977 11 51.0 54.1 -3.1 4 68 1963 2012 1963 1967 bottom-tenth 12 52.8 55.6 -2.8 3 69 1963 2012 1963 1967 bottom-tenth 1977 18 49.1 51.9 -2.8 2 67 1979 2017 1968 1967 bottom-tenth 1978 24 53.2 55.6 -2.4 3 65 1978 2017 1964 1967 bottom-tenth 1979 36 53.3 55.5 -2.2 2 62 1979 2022 1968 1967 bottom-tenth 48 53.4 55.5 -2.1 1 59 1966,1968,1970,1980 2019,2020,2022 1966 1967 lowest 1966,1970,1980 60 53.5 55.4 -1.9 3 54 1967,1970 2020 1967 1966 bottom-tenth