1991-2020 Degrees Fahrenheit 1 59.1 60.0 -0.9 45 33 1964 1997 1983 1984 normal 2 59.2 58.8 0.4 61 17 1964 1992 1983 1984 top-third 1988,1990,2019 3 56.8 57.8 -1.0 45 33 1948 1992 1983 1984 normal 2003 4 55.6 56.8 -1.2 41 36 1948 1992 1983 1984 normal 1957,1979 5 53.8 55.7 -1.9 28 49 1949 2014,2015,2016 1982 1984 normal 1968 6 52.9 55.0 -2.1 26 51 1949 2015 1979 1984 normal 1951,1957,1968 7 53.1 55.2 -2.1 26 51 1949 2015 1979 1984 normal 1957 8 54.0 56.2 -2.2 26 51 1949 2015 1979 1984 normal 9 55.8 57.2 -1.4 32 45 1949 2015 1983 1984 normal 10 56.7 58.0 -1.3 32 45 1949 2015 1983 1984 normal 1951,1958,1990 11 57.6 58.6 -1.0 41 35 1949 2015 1983 1984 normal 1981,2007 12 57.9 58.9 -1.0 38 37 1949 2015 1983 1984 normal 2001 18 57.2 57.6 -0.4 50 24 1949,1950 2015,2016 1983 1984 top-third 24 59.0 58.8 0.2 60 13 1950 2016 1984 1985 top-third 36 58.4 58.8 -0.4 48 23 1950 2016 1984 1985 top-third 48 58.1 58.8 -0.7 37 32 1951,1952,1955,1956 2018 1984 1984 normal 1984 60 58.1 58.7 -0.6 36 32 1952,1953,1956 2018 1984 1984 normal 1984,2002,2003