1991-2020 Degrees Fahrenheit 1 19.1 16.2 2.9 64 22 1977 2006 1994 1992 top-third 2 22.1 19.0 3.1 71 15 1977 2002 1994 1992 top-third 3 27.7 24.3 3.4 77 9 1977 2002 1994 1995 top-tenth 4 34.0 30.6 3.4 80 6 1977 2002 1994 1995 top-tenth 5 40.2 37.2 3.0 80 6 1977 2016 1994 1995 top-tenth 6 44.8 43.0 1.8 78 8 1977 2002,2012 1994 1942 top-tenth 2022 7 48.5 47.5 1.0 71 15 1977 2012 1994 1964 top-third 8 51.3 50.2 1.1 71 15 1952 2012 1994 1989 top-third 9 52.4 51.3 1.1 72 14 1946 2012 1994 1989 top-third 2021 10 51.8 50.8 1.0 71 15 1951 2002,2012 1994 1989 top-third 11 50.3 49.3 1.0 67 18 1951 2013,2017 1994 1989 top-third 12 47.3 46.9 0.4 67 18 1951 2013 1994 1992 top-third 1992,2008 18 44.5 45.6 -1.1 39 46 1952 2013 1994 1992 normal 1959,1975,2020 24 45.3 46.9 -1.6 27 57 1952 2013 1994 1993 bottom-third 1944,1957 36 45.3 46.9 -1.6 23 60 1952,1953 2013 1994 1994 bottom-third 1975,1986,1994 48 45.8 46.9 -1.1 41 41 1953,1969,1973 2002,2013,2019 1994 1993 normal 60 46.0 46.9 -0.9 48 33 1952,1970 2002,2003 1994 1993 normal 1957