1991-2020 Degrees Fahrenheit 1 56.8 55.4 1.4 55 21 1967 2015 1985 1982 top-third 2 52.2 49.2 3.0 71 5 1967 2010 1985 1986 top-tenth 3 45.4 42.8 2.6 70 6 1967 2012 1985 1977 top-tenth 2022 4 38.0 37.4 0.6 52 23 1967 2012 1985 1981 top-third 1976 5 33.9 33.7 0.2 52 22 1971 2012 1985 1977 top-third 6 31.5 32.4 -0.9 42 31 1971 2012 1984 1985 normal 1987,1988 7 32.1 32.9 -0.8 45 28 1971 2012 1984 1985 normal 1958,1975,2011 8 34.0 34.8 -0.8 43 30 1971 2012 1984 1985 normal 1958 9 36.6 37.5 -0.9 40 33 1971 2012 1984 1985 normal 10 39.3 40.5 -1.2 40 33 1971 2012 1984 1985 normal 1955,1958,1976,1997 11 41.8 43.0 -1.2 37 35 1963 2012 1984 1985 normal 1952,1997 12 43.3 44.8 -1.5 30 41 1963 2012 1984 1985 normal 1990 18 39.4 40.8 -1.4 33 34 1971 2017 1985 1984 normal 1984 24 43.7 45.0 -1.3 35 30 1966,1967,1971,1978 2013 1985 1985 normal 1958,1985 36 43.5 45.1 -1.6 29 31 1967 2023 1984 1985 normal 48 43.8 45.1 -1.3 31 25 1966,1968 2013,2023 1985 1956 normal 60 43.5 45.1 -1.6 27 25 1967 2013,2023 1985 1958 normal 1987