1991-2020 Degrees Fahrenheit 1 60.3 60.4 -0.1 56 23 1964 1997 2008 2006 top-third 2 58.8 59.2 -0.4 54 25 1964 1992 2008 2005 top-third 2022 3 57.4 58.1 -0.7 47 32 1948 1992 2008 2007 normal 4 56.3 57.1 -0.8 50 28 1948 1992 2008 2007 normal 1995,2002 5 55.5 56.0 -0.5 51 27 1949 1992,2014 2008 2005 normal 2013 6 54.5 55.4 -0.9 45 33 1949 2015 2008 2007 normal 1980,2007 7 55.1 55.6 -0.5 50 28 1949 2015 2008 2006 normal 1989,1994,1998,2002 8 56.3 56.6 -0.3 53 25 1949 2015 2008 2005 top-third 9 57.3 57.6 -0.3 55 23 1949 2015 2008 2005 top-third 1998,2019 10 58.1 58.4 -0.3 55 23 1949 2015 2008 2005 top-third 1978 11 58.6 58.9 -0.3 54 23 1949 2015 2008 2005 top-third 1978,1989 12 58.9 59.3 -0.4 50 26 1949 2015 2008 2005 normal 1991 18 57.2 57.9 -0.7 45 30 1950 2015 2008 2007 normal 1960,1986,2010,2013 24 58.6 59.2 -0.6 42 32 1950 2016 2008 2007 normal 1981,1991 36 58.6 59.2 -0.6 43 29 1950 2016 2008 2007 normal 1960,1984,2011 48 58.6 59.2 -0.6 42 28 1952 2017,2018 2002 2008 normal 1984,1985 60 58.9 59.1 -0.2 45 23 1952,1953,1956 2018 2003 2008 normal 1999