1991-2020 Degrees Fahrenheit 1 62.3 59.7 2.6 81 11 1978 2017 1943 1944 top-third 2 57.7 57.7 0.0 63 28 1978 2017 1943 1933 top-third 3 56.7 57.7 -1.0 51 40 1978 2017 1943 1939 normal 2002,2011 4 57.2 59.3 -2.1 35 56 1977 2017 1942 1943 normal 1987 5 -99 62.2 -99 -99 -99 1977 2017 normal 6 -99 65.5 -99 -99 -99 1977 2017 normal 7 -99 68.4 -99 -99 -99 1977 2017 normal 8 -99 70.5 -99 -99 -99 1977 2017 normal 9 -99 72.0 -99 -99 -99 1977 2017 normal 10 -99 72.7 -99 -99 -99 1977 2017 normal 11 -99 72.6 -99 -99 -99 1977 2017 normal 12 -99 71.9 -99 -99 -99 1977 2017 normal 18 -99 69.8 -99 -99 -99 1978 2017 normal 24 -99 71.9 -99 -99 -99 1978 2017 normal 36 -99 71.9 -99 -99 -99 1979 2018 normal 48 -99 71.9 -99 -99 -99 1980 2019 normal 60 -99 71.9 -99 -99 -99 1981 2020,2021 normal