1991-2020 Degrees Fahrenheit 1 65.3 73.3 -8.0 2 74 1993 2021 1992 1991 bottom-tenth 2 65.4 68.9 -3.5 7 69 1993 2021 1982 1991 bottom-tenth 3 62.9 64.4 -1.5 18 58 1950 1988 1983 1991 bottom-third 1972 4 59.3 59.7 -0.4 44 32 1950 1988 1991 1988 normal 1996,2020 5 56.1 55.4 0.7 57 19 1951 2012 1991 1988 top-third 2003 6 53.3 51.0 2.3 67 9 2019 2016 1991 1988 top-third 7 50.6 47.6 3.0 71 5 1950 2016 1991 1961 top-tenth 2015 8 48.5 45.0 3.5 72 3 1950 2016 1991 1992 top-tenth 9 46.7 44.0 2.7 69 6 1979 2016 1991 1961 top-tenth 10 46.5 44.4 2.1 66 9 1979 2016 1991 1988 top-third 1987 11 47.8 46.0 1.8 66 9 1979 2016 1991 1988 top-third 12 50.0 48.1 1.9 69 6 1979 2016 1991 1961 top-tenth 2015 18 50.7 49.1 1.6 69 6 1979 2016 1991 1988 top-tenth 24 49.1 48.1 1.0 64 10 1979 2016 1991 1988 top-third 36 48.6 48.1 0.5 60 13 1952 2017 1991 1992 top-third 2005 48 48.0 48.2 -0.2 53 19 1952 2015,2016 1991 1990 top-third 1983,2004,2010,2012,2019,2022 60 48.3 48.2 0.1 57 14 1969 2016 1991 1992 top-third 2013