1991-2020 Degrees Fahrenheit 1 53.9 51.2 2.7 74 20 1924 1977 2000 1999 top-third 2 47.4 44.7 2.7 80 14 1909 1977 2000 1999 top-third 1985 3 39.3 37.7 1.6 75 17 1950 2010 1997 2000 top-third 1958,1973 4 30.2 30.8 -0.6 59 33 1917 1998 1997 2000 normal 2004 5 27.0 25.6 1.4 74 18 1950 1998 1997 2000 top-third 6 22.3 23.2 -0.9 61 29 1950,1979 1998 1997 2000 top-third 1926 7 23.2 23.7 -0.5 65 23 1979 2012 1997 2000 top-third 1915,1988 8 25.8 25.9 -0.1 64 23 1920 2012 1997 2000 top-third 9 28.8 29.1 -0.3 63 22 1920 2012 1997 2000 top-third 1919 10 32.3 32.5 -0.2 63 21 1920 2012 1997 2000 top-third 11 35.4 35.4 0.0 63 21 1920 2012 1997 2000 top-third 2005 12 37.2 37.5 -0.3 60 22 1979 2012 1997 2000 top-third 1958,1981 18 34.0 32.7 1.3 66 13 1951 1999 1997 2000 top-third 24 38.6 37.5 1.1 67 10 1951 1999,2017 1998 2000 top-third 2006 36 39.0 37.4 1.6 68 4 1952 2000 1999 2000 top-tenth 2018 48 39.6 37.4 2.2 66 1 1952,1953 2001 2000 2001 highest 60 38.7 37.3 1.4 61 2 1970 2002 2000 2001 top-tenth