1901-2000 Degrees Fahrenheit 1 29.9 23.8 6.1 117 13 1977 1932 1973 1950 top-tenth 2 29.4 25.3 4.1 112 17 1918 1932 1973 1972 top-third 1913 3 31.9 28.5 3.4 114 15 1918 1932 1973 1950 top-third 4 35.5 32.6 2.9 110 19 1918 1932 1973 1972 top-third 1937,1947,1991,2019 5 40.1 37.3 2.8 114 15 1918 1932 1973 1972 top-third 1937 6 44.3 41.6 2.7 113 16 1918 1932 1973 1972 top-third 2002 7 47.2 44.9 2.3 112 17 1918 1932 1973 1972 top-third 8 49.3 46.8 2.5 114 15 1918 1932,2017 1973 1972 top-third 1950,1972 9 49.3 47.2 2.1 111 18 1918 2019 1973 1960 top-third 1960 10 48.6 46.6 2.0 110 19 1918 2020 1973 1960 top-third 1901,1992 11 47.7 45.3 2.4 116 13 1918 2012,2017 1973 1932 top-tenth 2011 12 45.6 43.5 2.1 112 17 1918 2013,2021 1973 1950 top-third 1991,2011 18 44.5 42.9 1.6 106 22 1905 2020 1973 1950 top-third 1932,2000,2016 24 44.5 43.5 1.0 94 34 1918 2013,2021 1973 1950 top-third 36 44.5 43.5 1.0 98 29 1918 2021 1973 1934 top-third 1923,1924,1976,1987,1991 48 44.4 43.5 0.9 96 30 1918 2022 1973 1974 top-third 1991 60 44.0 43.5 0.5 82 43 1906,1919,1968 2021 1973 1958 normal 1924,1932,1933,1956,1957,1958,1998