1991-2020 Degrees Fahrenheit 1 53.6 51.1 2.5 68 12 1976 1985 1993 1990 top-third 2 56.3 56.2 0.1 55 25 1976 1985 1993 1990 top-third 1971 3 60.4 61.5 -1.1 42 38 1976 2016 1992 1993 normal 2014 4 64.2 65.8 -1.6 31 49 1976 2007 1992 1993 normal 1945,1960,1965,2012,2014 5 67.2 68.6 -1.4 43 37 1967 2016 1992 1993 normal 1949,1968 6 68.8 69.9 -1.1 48 32 1967 2010 1992 1993 normal 7 68.1 69.7 -1.6 38 41 1967 2010 1992 1993 normal 8 67.5 68.5 -1.0 47 32 1967 2010 1992 1993 normal 1987 9 65.7 66.6 -0.9 48 31 1967 2010 1992 1993 normal 1973 10 63.6 64.4 -0.8 52 27 1967 2016,2017 1993 1991 normal 1945,1977,2000 11 61.1 62.3 -1.2 44 35 1967 2017 1992 1993 normal 12 59.3 60.9 -1.6 38 41 1967 2016 1988 1993 normal 18 62.9 63.9 -1.0 52 27 1967 2017 1993 1991 normal 1949,1985 24 59.6 60.8 -1.2 44 34 1967 2017 1993 1993 normal 1993 36 59.5 60.8 -1.3 42 35 1964,1968,1969 2018 1989 1993 normal 48 60.0 60.8 -0.8 49 27 1969 2019 1990 1993 normal 1999 60 60.3 60.7 -0.4 54 21 1967 2020 1993 1993 top-third 1993,2001,2004