1901-2000 Degrees Fahrenheit 1 18.2 10.8 7.4 105 24 1983 1939 2000 1999 top-third 2 27.9 18.3 9.6 126 3 1927 1999 2000 1999 top-tenth 3 32.6 26.7 5.9 125 4 1919 2015 2000 1999 top-tenth 1953 4 38.8 33.9 4.9 125 4 1919 2015 2000 1931 top-tenth 2016,2021 5 44.8 40.2 4.6 126 3 1985 2015 2000 2001 top-tenth 6 48.9 44.9 4.0 125 4 1985 2015 2000 2001 top-tenth 7 51.0 47.4 3.6 124 5 1985 2021 2000 1931 top-tenth 8 51.6 48.1 3.5 126 3 1927 2021 2000 2001 top-tenth 9 50.5 47.2 3.3 125 4 1927 2015 2000 1987 top-tenth 10 47.9 44.8 3.1 122 7 1951 2021 2000 1999 top-tenth 1999 11 43.9 41.6 2.3 114 15 1917 1987 2000 1999 top-third 2010 12 41.5 38.5 3.0 118 11 1950 1987 2000 1999 top-tenth 18 42.2 40.6 1.6 103 25 1917 2016 1997 2000 top-third 1939,1990 24 40.9 38.5 2.4 115 13 1917,1951 2016 1997 2000 top-tenth 1991 36 41.3 38.5 2.8 120 7 1918,1951 2017 1998 2000 top-tenth 48 41.7 38.5 3.2 125 1 1919 2001 2000 2001 highest 60 41.2 38.4 2.8 123 2 1899 2002 2000 2001 top-tenth