1991-2020 Degrees Fahrenheit 1 19.9 23.5 -3.6 32 53 1949 2006 1972 1971 normal 2 17.9 23.4 -5.5 17 67 1949 1958 1972 1971 bottom-third 3 23.1 26.8 -3.7 17 67 1979 2021 1972 1971 bottom-third 4 27.6 31.7 -4.1 11 72 1979 2000 1956 1972 bottom-third 2010 5 32.7 37.2 -4.5 10 73 1979 2022 1962 1972 bottom-third 6 38.7 42.6 -3.9 8 75 1986 2021 1956 1972 bottom-tenth 1956,1993 7 42.3 46.7 -4.4 5 78 1979 2022 1952 1972 bottom-tenth 1985 8 45.0 48.7 -3.7 6 77 1952,1979 2022 1952 1972 bottom-tenth 9 45.9 49.3 -3.4 7 76 1979 2022 1956 1972 bottom-tenth 10 45.5 48.9 -3.4 5 78 1952 2022 1956 1972 bottom-tenth 1985 11 45.1 47.8 -2.7 11 70 1952 2016 1972 1971 bottom-third 12 43.8 46.1 -2.3 15 66 1952 2016 1972 1971 bottom-third 1985,1994 18 42.3 44.9 -2.6 13 66 1952 2013,2022 1957 1972 bottom-third 1976 24 43.7 46.0 -2.3 8 69 1950 2017 1953 1972 bottom-tenth 1944,1949,1979 36 44.0 46.0 -2.0 8 65 1952 2018 1953 1972 bottom-third 48 44.1 46.0 -1.9 7 62 1952 2019 1953 1972 bottom-tenth 1945,1986 60 44.2 46.0 -1.8 6 59 1952,1953 2008,2009,2020 1954 1972 bottom-tenth 1950,1987