1991-2020 Degrees Fahrenheit 1 59.3 56.9 2.4 63 13 1961 2017 1980 1960 top-third 2 50.5 51.5 -1.0 34 42 1975 2012 1980 1979 normal 1989 3 46.1 47.1 -1.0 39 37 1958 2017 1980 1977 normal 1970 4 41.7 44.1 -2.4 21 55 1978 2017 1980 1976 bottom-third 5 40.7 43.0 -2.3 24 52 1978 2017 1980 1976 bottom-third 1966 6 41.1 43.6 -2.5 19 56 1977 2012 1980 1980 bottom-third 1980 7 42.9 45.5 -2.6 13 62 1977 2017 1978 1980 bottom-third 1956,1969 8 46.3 48.3 -2.0 18 56 1977 2017 1980 1979 bottom-third 1965 9 49.7 51.3 -1.6 23 51 1977 2017 1980 1979 bottom-third 1979 10 52.4 53.7 -1.3 25 49 1977 2017 1980 1976 normal 1993 11 53.9 55.4 -1.5 21 53 1977 2017 1980 1979 bottom-third 1962,1965,1979,1993 12 54.7 56.2 -1.5 22 52 1977 2017 1980 1979 bottom-third 1979 18 50.2 52.0 -1.8 16 58 1978 2017 1980 1976 bottom-third 1997 24 54.4 56.1 -1.7 13 60 1978 2017 1980 1977 bottom-third 1977,2015 36 54.5 56.1 -1.6 11 61 1979 2018 1980 1976 bottom-third 1966,1968,1971 48 54.2 56.1 -1.9 5 66 1980 2019,2020 1980 1979 bottom-tenth 1970,1979 60 53.6 56.0 -2.4 1 69 1981 2020 1981 1980 lowest