1991-2020 Degrees Fahrenheit 1 48.9 47.5 1.4 107 23 1943 2023 1997 1991 top-third 2 43.7 41.3 2.4 120 10 1926 2012 1997 1991 top-tenth 2016 3 39.8 36.4 3.4 126 4 1934 2012 1997 1998 top-tenth 4 37.1 33.2 3.9 125 5 1904 2012 1997 1998 top-tenth 5 35.7 32.6 3.1 122 6 1904 2012 1997 1998 top-tenth 6 35.7 33.8 1.9 116 10 1904 2012 1997 1991 top-tenth 7 37.5 36.2 1.3 115 11 1918 2012 1997 1991 top-tenth 2008,2021 8 40.4 39.6 0.8 113 13 1918 2012 1997 1991 top-tenth 2000 9 43.5 43.1 0.4 110 16 1904 2012 1997 1991 top-third 1921,1949 10 46.3 46.0 0.3 110 16 1904 2012,2023 1997 1991 top-third 11 48.2 48.0 0.2 110 16 1904 2012 1997 1991 top-third 12 48.7 48.9 -0.2 106 20 1918 2012,2023 1997 1995 top-third 1976 18 43.6 43.8 -0.2 98 24 1905 2017,2023 1997 1992 top-third 24 48.4 48.8 -0.4 98 24 1905 2017 1997 1992 top-third 1954 36 47.8 48.8 -1.0 88 30 1906 2023 1996 1997 top-third 1955,2005 48 48.1 48.8 -0.7 87 28 1906 2023 1997 1993 top-third 1993 60 47.7 48.7 -1.0 82 30 1906,1918,1920 2023 1997 1995 top-third 1994