1991-2020 Degrees Fahrenheit 1 35.4 33.5 1.9 76 32 1985 2001 1911 1913 top-third 2 44.8 40.6 4.2 100 8 1959 1963 1913 1914 top-tenth 3 50.1 47.4 2.7 101 6 1911,1959 1931 1913 1914 top-tenth 2005,2007 4 54.8 52.5 2.3 97 9 1985 2016 1913 1914 top-tenth 1948 5 58.7 56.1 2.6 102 4 1992 1931 1913 1914 top-tenth 6 60.2 58.0 2.2 99 7 1985 1931 1913 1914 top-tenth 7 59.9 57.9 2.0 97 9 1967 1931 1913 1914 top-tenth 1963 8 58.0 56.3 1.7 93 13 1996 1931 1913 1914 top-third 1939,1948,1998 9 54.9 53.5 1.4 90 16 1951,1996 2012 1913 1914 top-third 1998 10 50.4 50.0 0.4 75 31 1917 2012 1913 1914 top-third 1953,1991 11 47.8 46.8 1.0 87 18 1917 2012 1913 1914 top-third 1949 12 46.2 44.6 1.6 97 8 1917 2012 1913 1914 top-tenth 1934,2005 18 50.7 49.1 1.6 97 6 1951 2012 1913 1914 top-tenth 2021 24 45.2 44.6 0.6 84 18 1951 2017 1913 1914 top-third 36 44.3 44.6 -0.3 64 36 1952 2017 1914 1914 normal 1948,2003,2009 48 -99 44.6 -99 -99 -99 1918 1934 normal 60 -99 44.6 -99 -99 -99 1969,1997 1934 normal