1991-2020 Degrees Fahrenheit 1 40.5 33.3 7.2 81 3 1977 2023 2005 1950 top-tenth 2 37.3 35.9 1.4 67 17 1977 2016 2005 2002 top-third 1949,2021 3 41.2 39.6 1.6 71 12 1977 2016 2005 2002 top-third 1950 4 45.5 44.1 1.4 70 13 1977 2016 2005 2002 top-third 2020 5 51.1 49.2 1.9 76 7 1977 2016 2005 2002 top-tenth 2021 6 55.8 53.7 2.1 77 6 1977 2016 2005 2002 top-tenth 7 59.1 57.2 1.9 76 7 1977 2016 2005 2006 top-tenth 2020 8 61.0 59.2 1.8 75 7 1977 2016 2005 2006 top-tenth 9 60.8 59.7 1.1 71 11 1977 2016 2005 2002 top-third 2008,2019 10 60.2 59.2 1.0 71 11 1977 2016 2005 2002 top-third 11 58.3 57.7 0.6 68 13 1961 2016 2005 2002 top-third 1992,2008 12 56.5 55.9 0.6 65 16 1959 2013,2017 2005 2002 top-third 18 55.3 55.1 0.2 61 19 1964 2017 2005 2003 top-third 24 56.0 55.8 0.2 61 17 1964 2013 2005 2003 top-third 1999,2011 36 55.3 55.8 -0.5 50 25 1963,1970 2023 2005 2004 top-third 48 55.4 55.7 -0.3 50 22 1964 2023 2004 2005 top-third 2000 60 55.7 55.7 0.0 51 18 1965 2023 2005 2003 top-third 2007,2008