1991-2020 Degrees Fahrenheit 1 45.4 47.7 -2.3 27 48 1977 1950 2003 2007 normal 2 49.4 48.9 0.5 50 25 1977 1950 2006 2007 top-third 1997 3 51.1 51.2 -0.1 43 31 1977 1974 2004 2007 normal 1986 4 55.3 54.8 0.5 50 24 1977 2017 2007 2006 top-third 2012 5 59.5 59.1 0.4 52 22 1977 2017 2007 2006 top-third 1973 6 63.8 62.9 0.9 62 12 1977 2017 2007 2006 top-third 2006,2013 7 66.1 65.7 0.4 57 17 1977 2017 2007 2006 top-third 1957 8 67.8 67.4 0.4 57 17 1977 2017 2007 2006 top-third 1955,2022 9 68.2 68.0 0.2 56 18 1977 2017 2007 2006 top-third 2006 10 67.6 67.6 0.0 49 25 1977 2017 2006 2007 normal 1979,2002,2022 11 66.9 66.7 0.2 55 19 1977 2017 2007 2005 top-third 1955,1986,2022 12 65.3 65.4 -0.1 51 23 1977 2017 2007 2007 top-third 1960,1983,1986,2007 18 64.5 64.5 0.0 50 22 1969 2017,2020 2006 2007 top-third 1955,2006 24 65.3 65.4 -0.1 48 24 1970 2020 2007 2006 top-third 1951 36 65.3 65.3 0.0 51 19 1970 2019,2021 2006 2007 top-third 1954,1955,1956,2009 48 65.4 65.3 0.1 58 10 1970 2020 2007 1958 top-third 1953,1957,2017 60 65.2 65.2 0.0 51 15 1970 2020,2021 2007 1991 top-third 1955,1959,1991,2012