1991-2020 Degrees Fahrenheit 1 63.8 61.4 2.4 65 11 1952 2016 1948 1949 top-third 2 65.9 67.1 -1.2 32 44 1976 2019 1948 1949 normal 3 69.7 71.2 -1.5 25 51 1976 2007 1948 1949 bottom-third 1961,1997,2011 4 72.6 73.5 -0.9 32 44 1976 2007 1948 1949 normal 1962 5 73.4 74.2 -0.8 34 42 1976 2007 1949 1948 normal 6 72.8 73.3 -0.5 42 34 1976 2007 1948 1949 normal 1987,2004 7 70.5 71.5 -1.0 30 46 1976 2010,2019 1949 1948 normal 1963,1978 8 67.8 68.9 -1.1 33 43 1976 2007 1949 1948 normal 1957,1980,1983,2003 9 65.1 66.0 -0.9 39 37 1958 2016 1949 1948 normal 1962,1973 10 63.2 63.4 -0.2 52 24 1979 2012,2017,2019 1948 1949 top-third 11 61.3 61.5 -0.2 53 21 1978 2016 1949 1949 top-third 1957,2008 12 60.4 60.6 -0.2 53 21 1978 2016 1949 1949 top-third 18 64.4 64.8 -0.4 50 24 1977 2017 1949 1949 top-third 24 -99 60.6 -99 -99 -99 1979 2017 normal 36 -99 60.6 -99 -99 -99 1979 2018 normal 48 -99 60.6 -99 -99 -99 1979 2019 normal 60 -99 60.5 -99 -99 -99 1964 2020 normal