1901-2000 Degrees Fahrenheit 1 33.8 23.8 10.0 128 2 1977 1932 1949 1937 top-tenth 1937,2023 2 31.1 25.3 5.8 124 5 1918 1932 1949 1937 top-tenth 3 32.1 28.5 3.6 116 13 1918 1932 1948 1949 top-tenth 1993 4 36.7 32.6 4.1 125 4 1918 1932 1949 1932 top-tenth 2007,2021 5 40.0 37.3 2.7 112 17 1918 1932 1949 1937 top-third 2013 6 44.0 41.6 2.4 110 19 1918 1932 1949 1937 top-third 1960 7 47.5 44.9 2.6 113 16 1918 1932 1949 1932 top-third 8 49.3 46.8 2.5 114 15 1918 1932,2017 1949 1932 top-third 1972,1974 9 49.4 47.2 2.2 114 15 1918 2019 1949 1932 top-third 1901,1999 10 48.5 46.6 1.9 107 22 1918 2020 1949 1932 top-third 11 47.1 45.3 1.8 109 20 1918 2012,2017 1949 1932 top-third 12 45.7 43.5 2.2 114 15 1918 2013,2021 1949 1932 top-third 2006 18 44.9 42.9 2.0 111 17 1905 2020 1949 1950 top-third 24 45.1 43.5 1.6 109 19 1918 2013,2021 1949 1923 top-third 1923,2003 36 44.1 43.5 0.6 84 43 1918 2021 1949 1934 normal 1954,1995,1997 48 44.1 43.5 0.6 84 42 1918 2022 1949 1935 top-third 1932,1933,1935,1952,1953,1956 60 44.1 43.5 0.6 86 39 1906,1919,1968 2021 1949 1934 top-third 1934,1953,1954