1991-2020 Degrees Fahrenheit 1 71.8 74.8 -3.0 7 60 1976 1979 1952 1951 bottom-tenth 2 78.3 79.2 -0.9 24 43 1976 2015 1952 1951 normal 3 83.2 82.7 0.5 48 19 1976 2015 1952 1951 top-third 4 85.1 84.4 0.7 51 16 1976 1951 1952 1951 top-third 2009 5 85.7 85.1 0.6 49 18 1976 1951 1952 1951 top-third 2016 6 84.7 84.6 0.1 45 22 1976 1998 1952 1951 top-third 1955,2016 7 83.0 83.2 -0.2 39 27 1976 2011 1952 1952 normal 1999 8 80.7 81.3 -0.6 27 39 1976 2011 1952 1952 normal 2003 9 78.6 79.0 -0.4 36 29 1987 2011 1952 1952 normal 1995,2015 10 76.9 76.6 0.3 47 18 1970 2000 1952 1952 top-third 2020 11 75.2 74.7 0.5 49 16 1968,1970,1987 2000 1952 1952 top-third 1994,1999,2018 12 74.0 73.8 0.2 45 20 1970 2000 1952 1952 top-third 1989,2002 18 78.3 77.4 0.9 59 6 1977 2000 1952 1952 top-tenth 1954 24 -99 73.8 -99 -99 -99 1976 2000 normal 36 -99 73.8 -99 -99 -99 1970 2000 normal 48 -99 73.8 -99 -99 -99 1971 1956,2001 normal 60 -99 73.7 -99 -99 -99 1970,1977,1979 1956,2002 normal