1901-2000 Degrees Fahrenheit 1 56.3 58.3 -2.0 29 100 1951 1988 2004 2010 bottom-third 2 51.7 54.3 -2.6 15 114 1907 1988 1975 2010 bottom-third 1951 3 47.0 49.7 -2.7 13 116 1975 1988 1975 2010 bottom-tenth 1954 4 42.4 44.7 -2.3 19 110 1899 1910 2002 2010 bottom-third 1982 5 37.2 40.0 -2.8 13 116 1899 2016 1989 2010 bottom-tenth 1989 6 34.2 36.1 -1.9 25 104 1899 1992 1982 2010 bottom-third 1912,1920 7 32.0 33.9 -1.9 21 107 1917 1992 1982 2010 bottom-third 1903 8 31.4 33.4 -2.0 20 108 1899 1992 1979 2010 bottom-third 9 33.2 34.5 -1.3 27 101 1899 2016 1997 2010 bottom-third 1898,1975,1997 10 35.3 36.4 -1.1 37 91 1899 2016 1997 2010 bottom-third 2019 11 37.8 38.9 -1.1 32 96 1917 2016 1979 2010 bottom-third 12 40.1 41.1 -1.0 31 97 1917 2016 1993 2010 bottom-third 18 39.1 39.5 -0.4 48 80 1917 2016 1997 2010 normal 1933,1975,1983,1994 24 40.7 41.1 -0.4 41 86 1917 2016 1997 2010 bottom-third 1909,1921,1948,1986 36 41.0 41.1 -0.1 47 79 1899 2017 1997 2010 normal 1945,1947,1958,1974,1995,1997 48 41.4 41.1 0.3 74 51 1899,1952 2007,2016,2018 1997 2010 normal 1946,1986 60 41.8 41.1 0.7 83 41 1917,1952 2016 1998 2010 top-third