1991-2020 Degrees Fahrenheit 1 71.8 74.2 -2.4 21 108 1967 1936 1912 1911 bottom-third 2 73.5 74.8 -1.3 37 92 1967 1936 1910 1911 bottom-third 1966,1968,1997 3 72.0 73.8 -1.8 22 107 1967 1936 1910 1911 bottom-third 1928,1946,2009 4 70.1 71.3 -1.2 39 90 1967 1936 1910 1911 bottom-third 1897,1956,2004 5 67.3 68.0 -0.7 50 79 1907 2010 1910 1911 normal 1951,1965,1969,1983,2013,2021 6 62.4 64.1 -1.7 31 98 1950 2012 1907 1911 bottom-third 1906,1970,1979,2013 7 57.2 60.1 -2.9 13 116 1958 2012 1912 1911 bottom-tenth 8 52.8 56.6 -3.8 5 124 1978 2012 1912 1911 bottom-tenth 9 51.3 54.4 -3.1 11 117 1978 2012 1904 1911 bottom-tenth 1926,1971 10 50.0 53.4 -3.4 4 124 1978 2012 1904 1911 bottom-tenth 1920 11 50.6 53.7 -3.1 6 122 1978 2012 1904 1911 bottom-tenth 1918,1968,1970,1979 12 52.4 54.8 -2.4 13 115 1978 2017 1904 1911 bottom-tenth 1966 18 56.4 57.9 -1.5 37 91 1918 2017 1910 1911 bottom-third 1972 24 53.5 54.8 -1.3 34 93 1978 2017 1907 1911 bottom-third 1904,1926,1929,1965,1972,1976 36 53.3 54.7 -1.4 28 98 1979 2018 1907 1911 bottom-third 1926,1964,1984,1996,1998 48 53.8 54.7 -0.9 40 85 1980 2019 1908 1911 bottom-third 1913,1915,1917,1930,1931,1998 60 53.8 54.7 -0.9 42 82 1970,1981 2020 1910 1911 normal 1904,1910,1931,1959