1991-2020 Degrees Fahrenheit 1 35.8 34.8 1.0 58 28 1959 2001 1959 1954 top-third 2 43.2 42.2 1.0 60 26 1959 1963 1959 1958 top-third 1968 3 49.9 49.3 0.6 63 23 1951 2016 1959 1958 top-third 1971,1978,2013 4 55.9 54.9 1.0 66 20 1951 2016 1959 1953 top-third 1941 5 59.5 58.8 0.7 64 22 1951 2016 1959 1953 top-third 1938 6 60.5 60.7 -0.2 49 37 1951 2021 1959 1956 normal 1964,1970,2003 7 60.1 60.5 -0.4 47 39 1967 2021 1959 1956 normal 2003,2009 8 58.4 58.8 -0.4 48 38 1945,1951,1967 2021 1959 1958 normal 1976,1983,2013 9 54.3 56.0 -1.7 18 67 1951 2012,2021 1951 1959 bottom-third 1969,1975 10 50.7 52.5 -1.8 18 67 1951 2012 1951 1959 bottom-third 1947,1966 11 47.6 49.2 -1.6 29 56 1951 2012 1957 1959 normal 12 46.1 46.9 -0.8 44 41 1951 2012 1959 1958 normal 1980 18 50.5 51.5 -1.0 38 47 1951 2012 1959 1958 normal 2009 24 45.6 46.9 -1.3 35 49 1951 2017 1957 1959 normal 2019 36 46.0 46.9 -0.9 48 35 1952 2017 1959 1955 normal 1941,1949 48 45.9 46.9 -1.0 42 40 1952 2018 1959 1956 normal 1993 60 45.6 46.9 -1.3 31 50 1969 2002 1955 1959 normal 1949,1962