1991-2020 Degrees Fahrenheit 1 25.8 30.4 -4.6 23 79 1934 2017 1934 1933 bottom-third 2 24.5 29.3 -4.8 20 80 1978 2023 1934 1933 bottom-third 3 26.0 30.6 -4.6 19 81 1963 2023 1934 1933 bottom-third 1962 4 30.2 33.4 -3.2 26 72 1977 1932 1934 1933 bottom-third 1956,1962 5 33.9 37.3 -3.4 20 77 1977 1932 1934 1933 bottom-third 1981 6 38.8 41.8 -3.0 20 77 1977 1932 1934 1933 bottom-third 1996,2003 7 42.7 46.1 -3.4 15 82 1977 1932,2017 1934 1933 bottom-third 8 46.4 49.5 -3.1 15 82 1977 2023 1934 1933 bottom-third 1994 9 49.1 51.6 -2.5 21 76 1977 2017 1934 1933 bottom-third 1943 10 50.1 52.5 -2.4 20 77 1977 2016 1934 1933 bottom-third 1929,1940,1964 11 49.7 52.2 -2.5 22 75 1977 2020 1934 1933 bottom-third 1957,1973 12 48.2 51.1 -2.9 15 82 1941 2017,2020 1934 1933 bottom-third 1982,1993 18 44.4 48.0 -3.6 5 88 1941 2017 1935 1934 bottom-tenth 24 48.0 51.0 -3.0 3 90 1941 2017,2023 1926 1934 bottom-tenth 1968,1978 36 48.3 51.0 -2.7 5 84 1979 2022,2023 1935 1934 bottom-tenth 1968,1970 48 49.3 50.9 -1.6 26 60 1964,1980 2023 1931 1934 bottom-third 1940,1949,1983,1996 60 49.3 50.9 -1.6 27 56 1944,1945,1965 2023 1935 1934 bottom-third 1978,1997