1901-2000 Degrees Fahrenheit 1 39.0 32.7 6.3 118 12 1978 2017 1999 1998 top-tenth 1998 2 34.3 31.6 2.7 93 37 1978 1932 1996 1999 top-third 3 34.6 32.1 2.5 97 32 1977 1932 1996 1999 top-third 1921,1983 4 37.9 34.6 3.3 115 14 1977 1932 1998 1999 top-third 5 40.8 38.4 2.4 110 19 1977 1932 1998 1999 top-third 6 44.5 42.7 1.8 105 24 1977 1932 1998 1999 top-third 2018 7 48.2 46.7 1.5 104 25 1977 1932 1998 1999 top-third 1957,1976,1992 8 51.6 49.8 1.8 110 19 1977 1932 1998 1999 top-third 1909,2005 9 53.6 51.9 1.7 112 17 1977 1932 1998 1999 top-third 1901,1922 10 54.3 52.7 1.6 108 21 1977 1932 1998 1999 top-third 1907,1909 11 54.3 52.5 1.8 114 15 1977 1932 1998 1999 top-third 1937,2006 12 52.8 51.6 1.2 102 27 1977 2017 1998 1999 top-third 2011 18 50.5 48.6 1.9 115 13 1978 2017 1998 1999 top-tenth 2019 24 53.3 51.6 1.7 118 10 1978 2017 1999 1992 top-tenth 1923,1933,2019,2022 36 52.7 51.6 1.1 109 18 1979 2018 1999 1993 top-third 1923,1924,1933,1951,1993,2012 48 52.4 51.6 0.8 102 24 1980 2020 1999 1993 top-third 1922,1923,1993,2003,2012 60 52.2 51.6 0.6 89 36 1981 2020 1999 1995 top-third 1924,1936,1949,1952,1991,1994,2011