1991-2020 Degrees Fahrenheit 1 83.3 88.7 -5.4 4 64 1965 2021 1965 1966 bottom-tenth 2 80.4 84.3 -3.9 7 61 1965 2001,2006 1965 1966 bottom-tenth 3 74.6 80.3 -5.7 1 67 1967,1975 2000 1967 1966 lowest 1975 4 72.2 76.8 -4.6 3 65 1975 2004 1965 1966 bottom-tenth 1998 5 69.8 73.5 -3.7 6 62 1975 2014,2015,2016,2017 1965 1966 bottom-tenth 6 67.0 70.8 -3.8 3 63 1975 2014 1955 1966 bottom-tenth 7 65.4 68.7 -3.3 4 58 1975 2015 1965 1966 bottom-tenth 1965 8 65.3 68.1 -2.8 6 56 1975 1996 1965 1966 bottom-tenth 1977 9 66.3 69.1 -2.8 8 53 1975 1996,2015 1965 1966 bottom-third 1962 10 68.3 71.0 -2.7 8 53 1973 1996 1965 1966 bottom-third 11 70.6 73.1 -2.5 9 52 1973 1996 1965 1966 bottom-third 12 72.5 74.9 -2.4 9 52 1975 1996 1965 1966 bottom-third 18 71.3 73.5 -2.2 11 49 1976 2015 1966 1963 bottom-third 24 72.8 74.9 -2.1 9 47 1973,1975,1976 2018 1966 1963 bottom-third 1963,1970,1971 36 72.6 74.9 -2.3 6 45 1975,1977 2017,2018 1967 1963 bottom-third 1971 48 -99 74.9 -99 -99 -99 1975,1976 2018 normal 60 -99 74.8 -99 -99 -99 1977 2018 normal