1991-2020 Degrees Fahrenheit 1 36.2 37.7 -1.5 39 46 1979 2017 1948 1949 normal 2 40.4 36.5 3.9 76 9 1978 2023 1948 1949 top-third 3 40.1 37.6 2.5 76 9 1963 2023 1948 1949 top-third 1991 4 41.8 40.2 1.6 75 9 1977 2012 1948 1949 top-third 1995 5 46.0 43.8 2.2 77 7 1977 2017 1949 1950 top-tenth 6 49.4 48.3 1.1 72 12 1977 2017 1949 1949 top-third 1949,1972,1999 7 53.4 52.4 1.0 73 11 1977 2017 1949 1950 top-third 1999 8 56.8 55.7 1.1 75 9 1977 2017 1949 1950 top-third 1991,2021 9 58.9 57.8 1.1 74 9 1977 2017 1949 1950 top-third 10 59.5 58.6 0.9 73 10 1977 2012 1949 1950 top-third 1992 11 59.0 58.4 0.6 70 13 1977 2012 1949 1950 top-third 1999,2006,2007 12 57.8 57.3 0.5 68 15 1977 2012 1949 1950 top-third 2002 18 55.0 54.2 0.8 70 12 1941 2017 1949 1950 top-third 24 57.5 57.2 0.3 66 15 1968 2013 1949 1950 top-third 1999,2014 36 56.5 57.2 -0.7 51 28 1963,1968,1979 2013 1949 1950 normal 1951,1955,1976,1988,1996,1998,2005 48 56.6 57.2 -0.6 47 30 1964 2023 1949 1950 normal 60 56.6 57.1 -0.5 48 27 1965,1967,1968 2020,2023 1949 1950 normal 1991,1996,2005