1991-2020 Degrees Fahrenheit 1 30.7 41.6 -10.9 6 111 1912 2012 1924 1947 bottom-tenth 2 28.3 37.0 -8.7 3 113 1912 2017 1912 1947 bottom-tenth 1965 3 27.6 34.7 -7.1 5 109 1912 1986 1937 1947 bottom-tenth 1915,1929 4 27.5 33.7 -6.2 4 109 1912 2000 1915 1947 bottom-tenth 5 28.7 34.9 -6.2 3 110 1912 2000 1912 1947 bottom-tenth 6 33.6 37.7 -4.1 9 104 1912 2000 1929 1947 bottom-tenth 1984 7 38.6 41.7 -3.1 15 96 1912 2016 1937 1947 bottom-third 1937 8 43.6 45.7 -2.1 26 85 1912 2016 1937 1947 bottom-third 1984 9 47.3 49.1 -1.8 27 84 1912 2016 1942 1947 bottom-third 1936,1997 10 49.2 51.2 -2.0 19 91 1912 1935 1942 1947 bottom-third 1942 11 49.9 52.0 -2.1 20 89 1912 1935 1936 1947 bottom-third 12 49.7 51.7 -2.0 20 89 1912 1935 1936 1947 bottom-third 1958,1985,1996 18 44.7 47.1 -2.4 10 97 1916 1935 1930 1947 bottom-tenth 24 50.2 51.7 -1.5 20 86 1917 1935 1931 1947 bottom-third 1959,1970 36 50.3 51.7 -1.4 19 85 1917,1918 2017 1932 1947 bottom-third 1949,1970,1986,1996 48 50.5 51.7 -1.2 24 78 1918 2018 1933 1947 bottom-third 1961,1971,1974 60 50.5 51.7 -1.2 17 83 1925 2017 1933 1947 bottom-third 1949,1951,1975