1901-2000 Degrees Fahrenheit 1 17.8 25.2 -7.4 3 126 1909 1980 1909 1923 bottom-tenth 1898 2 26.4 29.4 -3.0 15 114 1972 2021 1919 1923 bottom-third 1932,1983 3 33.2 35.1 -1.9 15 114 1898 2021 1923 1923 bottom-third 1905,1912,1923,1929,1952,1992 4 38.8 40.7 -1.9 17 112 1898 2021 1923 1922 bottom-third 1918,1951 5 44.0 45.6 -1.6 15 114 1898 2021 1923 1922 bottom-third 1929,1951,1968,1993 6 47.6 49.1 -1.5 12 117 1898,1912 2021 1923 1922 bottom-tenth 1913 7 49.7 50.9 -1.2 17 112 1912 2021 1923 1922 bottom-third 1909,1927,1929,1930,2009 8 49.6 51.0 -1.4 11 118 1912 2021 1923 1922 bottom-tenth 1920,1928,1930 9 48.6 50.0 -1.4 8 121 1912 2021 1923 1923 bottom-tenth 1923,1928,1968 10 46.3 48.4 -2.1 2 127 1912 2012 1912 1923 bottom-tenth 11 44.8 46.5 -1.7 7 122 1912 2012,2017 1923 1922 bottom-tenth 1898,1920 12 42.7 44.6 -1.9 4 125 1912 2012 1912 1923 bottom-tenth 1898 18 44.3 46.1 -1.8 3 125 1912 1934 1917 1923 bottom-tenth 1899,1917,1929 24 43.0 44.6 -1.6 3 125 1913 2017 1913 1923 bottom-tenth 36 43.4 44.6 -1.2 6 121 1913,1914 2017 1920 1923 bottom-tenth 1918,1920,1930 48 44.0 44.6 -0.6 21 105 1915 2018 1920 1923 bottom-third 1909,1975,1976 60 43.9 44.6 -0.7 12 113 1916 2018 1921 1923 bottom-tenth 1906,1909,1914,1926,1927,1930,1931