1901-2000 Degrees Fahrenheit 1 6.1 12.4 -6.3 15 115 1912 2006 1929 1928 bottom-third 2009 2 11.9 15.4 -3.5 24 105 1977 2002 1929 1928 bottom-third 3 17.1 20.7 -3.6 13 116 1977 2002 1927 1929 bottom-tenth 4 24.3 27.3 -3.0 13 116 1977 2002 1927 1929 bottom-tenth 5 30.9 33.4 -2.5 11 118 1977 1932 1927 1929 bottom-tenth 1996 6 36.6 38.9 -2.3 10 119 1977 1932 1927 1929 bottom-tenth 1917 7 41.3 43.2 -1.9 12 117 1977 1932 1927 1929 bottom-tenth 1905,1979 8 43.8 45.8 -2.0 12 117 1918 1932 1927 1929 bottom-tenth 9 44.6 46.8 -2.2 7 122 1918 1932 1927 1929 bottom-tenth 10 44.6 46.4 -1.8 11 118 1918 1932 1927 1929 bottom-tenth 1920 11 43.4 44.7 -1.3 16 113 1918 2013 1929 1928 bottom-third 1936,1966,1970,1973 12 40.4 42.4 -2.0 8 121 1918 2013 1927 1929 bottom-tenth 18 39.5 41.2 -1.7 8 120 1918 2017 1927 1929 bottom-tenth 24 40.7 42.3 -1.6 5 123 1918 2000 1919 1929 bottom-tenth 36 41.1 42.3 -1.2 10 117 1918 2013 1929 1928 bottom-tenth 48 40.8 42.3 -1.5 3 123 1918 2002 1920 1929 bottom-tenth 60 41.1 42.3 -1.2 5 120 1918,1919,1920,1929 2003 1929 1928 bottom-tenth 1908,1921,1928