1991-2020 Degrees Fahrenheit 1 71.6 73.9 -2.3 27 49 1976 2020 1950 1949 normal 2 69.7 72.0 -2.3 23 52 1972 1991 1950 1949 bottom-third 2003 3 66.3 68.4 -2.1 24 51 1979 1991 1950 1949 bottom-third 1971 4 61.1 64.0 -2.9 15 60 1961 1991 1950 1949 bottom-third 5 56.1 59.0 -2.9 16 59 1950 1991,2012 1950 1949 bottom-third 1992,1996 6 51.5 54.2 -2.7 17 58 1978 2012 1950 1949 bottom-third 7 48.2 50.5 -2.3 25 50 1978 2012 1950 1949 bottom-third 1985 8 45.0 48.3 -3.3 12 63 1978 2012 1951 1950 bottom-third 1980,1996 9 43.9 47.7 -3.8 7 67 1978 2012 1951 1950 bottom-tenth 1970 10 45.0 48.3 -3.3 10 64 1978 2012 1951 1950 bottom-third 1972 11 46.5 49.9 -3.4 9 65 1978 2012 1951 1950 bottom-third 12 48.4 51.8 -3.4 9 65 1963,1978 2012 1951 1950 bottom-third 18 48.7 52.6 -3.9 2 71 1979 2012 1951 1950 bottom-tenth 1961 24 48.8 51.7 -2.9 9 63 1978 2017 1951 1950 bottom-third 36 49.7 51.6 -1.9 24 46 1979 2018 1951 1951 normal 1957,1973 48 -99 51.6 -99 -99 -99 1980 2019 normal 60 -99 51.5 -99 -99 -99 1981 2020 normal