1991-2020 Degrees Fahrenheit 1 22.9 28.1 -5.2 24 76 1977 1932 1984 1983 bottom-third 2 29.6 30.6 -1.0 59 41 1977 1932 1984 1983 normal 3 33.6 34.4 -0.8 59 39 1977 1932 1984 1983 normal 1942 4 39.6 39.0 0.6 75 22 1977 1932 1984 1983 top-third 1974,1998 5 43.7 44.1 -0.4 67 30 1977 1932 1984 1983 top-third 1928 6 48.5 48.6 -0.1 73 24 1977 1932 1984 1974 top-third 1947,1949 7 51.7 52.2 -0.5 70 27 1977 1932 1984 1974 top-third 8 54.0 54.3 -0.3 73 24 1977 2016 1984 1974 top-third 2015 9 54.3 54.9 -0.6 71 26 1977 2016 1984 1974 top-third 1937,1972 10 53.6 54.4 -0.8 70 27 1925 2016 1984 1974 top-third 1953,1958,2014 11 51.6 53.0 -1.4 54 43 1925 2012,2013,2020,2021,2023 1984 1980 normal 2009 12 50.2 51.1 -0.9 65 32 1925 2021 1984 1974 top-third 2014 18 49.0 50.2 -1.2 55 38 1941 2017 1983 1984 normal 1995,2010 24 49.9 51.0 -1.1 55 38 1926 2021 1984 1975 normal 1987 36 49.7 51.0 -1.3 50 39 1970 2022,2023 1984 1976 normal 1952,1974,1988,1994 48 49.5 50.9 -1.4 37 49 1971 2023 1984 1976 normal 1976 60 49.4 50.9 -1.5 30 53 1944,1945,1965,1968,1971 2023 1984 1978 normal 1935,1951,1975,1978