1991-2020 Degrees Fahrenheit 1 39.8 43.5 -3.7 7 68 1969 2015 1984 1995 bottom-tenth 2 46.1 49.5 -3.4 5 70 1970 2015 1986 1995 bottom-tenth 3 51.5 54.0 -2.5 4 71 1976 2015 1986 1995 bottom-tenth 4 54.8 56.8 -2.0 10 65 1976 2015 1993 1995 bottom-third 1973 5 55.8 57.5 -1.7 19 56 1976 2015 1995 1994 bottom-third 1961 6 55.6 56.5 -0.9 43 32 1971,1975,1976 2022 1995 1994 normal 1972,1997,2009,2019 7 53.6 54.5 -0.9 43 32 1975 2020 1995 1994 normal 1952,1966,1972,1998,2009 8 50.9 52.0 -1.1 45 30 1970,1975 2020 1995 1994 normal 1958,1966,1977,1985,1998 9 48.4 48.9 -0.5 52 23 1984 2020 1995 1990 top-third 1981,1990 10 45.6 45.7 -0.1 55 20 1984 2015 1995 1986 top-third 1986,2007 11 43.6 43.1 0.5 57 16 1979,1984 2018 1995 1981 top-third 12 42.6 42.0 0.6 58 15 1973 2018 1995 1981 top-third 18 46.5 46.8 -0.3 50 23 1973 2018 1995 1995 top-third 1995 24 42.2 42.0 0.2 54 17 1993 2018 1995 1996 top-third 36 41.9 41.9 0.0 52 17 1975 2018 1995 1996 top-third 1997 48 41.0 41.8 -0.8 42 25 1976 2020,2021 1995 1983 normal 60 40.3 41.7 -1.4 24 41 1977 2022 1995 1991 normal 1986,1987