1991-2020 Degrees Fahrenheit 1 48.8 47.6 1.2 90 39 1920 1981 1993 1992 top-third 2 45.5 43.9 1.6 114 15 1912 2012 1993 1992 top-third 3 39.7 39.7 0.0 92 35 1899 2012 1993 1992 top-third 1926 4 37.1 36.9 0.2 95 30 1912 1992 1993 1992 top-third 1943,1983 5 35.9 35.1 0.8 105 19 1912 1992 1993 1992 top-third 1943,1972 6 35.1 35.5 -0.4 85 36 1912 2000 1993 1992 top-third 2021 7 36.9 37.6 -0.7 83 36 1912 2000 1993 1992 top-third 1921 8 39.6 40.9 -1.3 66 52 1912 1981 1993 1992 normal 1996 9 43.0 44.4 -1.4 52 66 1912 1981 1993 1992 normal 1921,1959,1968 10 45.8 47.6 -1.8 44 74 1912 1981 1993 1992 normal 1951,1956,1959,1988 11 47.5 49.5 -2.0 39 78 1912 1981 1993 1992 bottom-third 12 48.6 50.2 -1.6 45 72 1912 1981 1993 1992 normal 1921,1978,1980 18 42.4 45.3 -2.9 15 97 1909,1916 2000 1980 1993 bottom-third 24 47.7 50.2 -2.5 15 95 1909 2000 1980 1993 bottom-third 1919,1921 36 49.1 50.2 -1.1 51 55 1918 2000 1986 1993 normal 1968,1969,1978 48 49.4 50.3 -0.9 60 42 1918 2002 1988 1993 normal 1954,1964,1966,1988,1997 60 49.6 50.3 -0.7 63 35 1912,1918,1920 2003 1989 1993 normal