1991-2020 Degrees Fahrenheit 1 41.3 44.3 -3.0 18 44 2014 2012 1978 1979 bottom-third 2 35.8 40.4 -4.6 7 55 2015 2012 1979 1977 bottom-third 3 34.6 38.3 -3.7 11 51 1978 2012 1979 1977 bottom-third 4 35.8 38.2 -2.4 21 41 1978 2012 1979 1976 normal 5 38.4 39.7 -1.3 23 36 1970 2012 1979 1976 normal 6 41.0 42.6 -1.6 23 36 1977 2012 1979 1976 normal 1966,2011 7 44.7 46.3 -1.6 21 38 1977 2017 1979 1976 normal 1987,1989 8 48.3 50.0 -1.7 20 39 1977 2017 1979 1976 normal 9 51.2 53.0 -1.8 16 43 1977 2017 1979 1976 bottom-third 1965,1996 10 52.9 55.0 -2.1 11 48 1977 2017 1979 1979 bottom-third 1979,2014 11 53.8 55.8 -2.0 10 49 1977 2012 1978 1979 bottom-third 1973,1984,2001,2014 12 53.6 55.8 -2.2 9 50 1977 2012,2020 1978 1979 bottom-third 1964,1969,1973,1984 18 49.0 51.3 -2.3 7 50 1978 2017 1979 1977 bottom-third 1971 24 53.7 55.7 -2.0 7 50 1978 2017 1979 1979 bottom-third 1979,1994 36 53.6 55.7 -2.1 5 50 1979 2022 1979 1978 bottom-tenth 48 53.3 55.7 -2.4 1 52 1980 2022 1980 1979 lowest 60 53.7 55.6 -1.9 5 46 1981 2020 1971 1979 bottom-tenth