1991-2020 Degrees Fahrenheit 1 36.7 34.1 2.6 106 23 1951 1910 1998 1999 top-third 2 32.3 30.1 2.2 104 25 2019 2016 1997 1999 top-third 1928,1997 3 30.1 28.4 1.7 106 23 1969 1992 1998 1999 top-third 4 31.3 27.7 3.6 118 10 1969 1992 1999 1992 top-tenth 5 33.7 28.9 4.8 126 2 1969 1992 1999 1992 top-tenth 1926 6 35.9 31.5 4.4 126 1 1969 2000 1999 2000 highest 7 38.2 35.2 3.0 121 6 1969 2012,2016 1998 1999 top-tenth 8 41.9 39.1 2.8 122 5 1969 1992,2012 1998 1999 top-tenth 9 44.3 42.3 2.0 118 9 1969 1999,2012 1998 1999 top-tenth 10 45.7 44.0 1.7 115 12 1969 2016 1998 1999 top-tenth 2007 11 46.0 44.7 1.3 112 15 1969 2016 1998 1999 top-third 1977,2008 12 45.5 44.5 1.0 105 22 1969 1931,2016 1998 1999 top-third 1940 18 41.7 40.2 1.5 119 6 1979 2016 1998 1999 top-tenth 1935 24 46.1 44.5 1.6 122 3 1979 2016 1999 2000 top-tenth 36 45.6 44.5 1.1 119 4 1952 2017 1999 2000 top-tenth 2015 48 44.6 44.6 0.0 100 21 1952 2016 1999 1992 top-third 1964,2003,2013,2014 60 44.0 44.6 -0.6 87 32 1952 2016 1999 1995 top-third 1936,1965,1989,1995,2021