1991-2020 Degrees Fahrenheit 1 29.0 30.5 -1.5 36 42 1979 2006 2004 2007 normal 2 30.0 32.2 -2.2 28 50 1984 1992 2001 2007 normal 3 34.9 36.3 -1.4 35 43 1977 2002 2001 2007 normal 2009 4 41.3 41.6 -0.3 46 32 1977 2002 2003 2007 normal 2020 5 47.4 47.2 0.2 54 24 1977 2022 2004 2007 top-third 1948,1966 6 53.4 52.4 1.0 64 14 1977 2022 2007 2006 top-third 1954,2023 7 57.1 56.3 0.8 60 17 1977 1955 2005 2007 top-third 1954 8 59.3 58.7 0.6 58 19 1977 1955 2005 2007 top-third 9 60.4 59.5 0.9 59 18 1977 2002,2013 2005 2007 top-third 2019 10 59.6 59.2 0.4 59 18 1962 2002,2013 2005 2007 top-third 1954 11 59.1 57.9 1.2 64 13 1962 2013 2005 2007 top-third 12 56.7 56.1 0.6 62 15 1979 2013 2005 2007 top-third 1954,2022,2023 18 55.5 54.8 0.7 65 12 1979 2013 2005 2007 top-third 1999,2002,2012 24 57.0 56.0 1.0 69 7 1962 2013 2006 2007 top-tenth 2001,2002 36 57.2 56.0 1.2 72 3 1963 2013 2007 2008 top-tenth 48 56.8 56.0 0.8 70 4 1962 2002 2007 2003 top-tenth 2013,2014 60 56.6 56.0 0.6 68 5 1963 2003 2007 2004 top-tenth 2019,2020,2021