1991-2020 Degrees Fahrenheit 1 63.6 63.5 0.1 54 21 1950 2007 1993 1983 top-third 2 63.5 64.5 -1.0 33 42 1950 2011 1993 1991 normal 1955 3 63.2 63.3 -0.1 56 19 1950 2011 1993 1958 top-third 1958,2008 4 60.5 60.5 0.0 54 21 1950 2012 1993 1958 top-third 5 56.8 57.0 -0.2 55 20 1975 2012 1993 1994 top-third 6 53.2 53.3 -0.1 55 20 1950,1975 2012 1993 1989 top-third 7 48.8 49.2 -0.4 54 21 1979 2020 1993 1986 top-third 1972,1981 8 45.2 45.2 0.0 53 22 1984 2018 1993 1986 top-third 9 42.2 42.2 0.0 52 21 1979 2018 1993 1986 top-third 2002 10 40.6 41.0 -0.4 47 26 1973 2018 1993 1986 normal 1963 11 40.7 41.3 -0.6 46 27 1973,1992 2018 1993 1989 normal 1951,1967,1989 12 41.7 42.5 -0.8 43 30 1973,1992 2018 1993 1990 normal 1951,1959,1989,1990 18 45.1 46.1 -1.0 43 30 1984 2018 1993 1990 normal 1989,1997 24 40.5 42.5 -2.0 19 52 1993 2018 1993 1991 bottom-third 1968,1979,1989 36 39.5 42.4 -2.9 3 66 1975 2018 1993 1992 bottom-tenth 48 39.9 42.3 -2.4 3 64 1976 2019,2020 1993 1993 bottom-tenth 1993 60 40.3 42.2 -1.9 9 56 1977 2020 1993 1991 bottom-third 1973