1991-2020 Degrees Fahrenheit 1 47.3 45.4 1.9 69 16 1960 2012 1967 1946 top-third 2 40.1 41.6 -1.5 34 51 2015 2012 1967 1961 normal 1982,1992,2005 3 36.7 39.5 -2.8 26 59 1940 2012 1966 1967 bottom-third 4 37.0 39.6 -2.6 32 53 1978 2012 1966 1967 normal 1947 5 38.2 41.2 -3.0 18 66 1940 2012 1966 1967 bottom-third 1956,1966 6 41.1 44.1 -3.0 15 69 1977 2012 1966 1967 bottom-third 1944 7 44.7 47.8 -3.1 7 77 1977 2012 1963 1967 bottom-tenth 1970 8 48.4 51.5 -3.1 7 77 1977 2012 1963 1967 bottom-tenth 9 51.4 54.6 -3.2 5 79 1977 2012 1963 1967 bottom-tenth 1982 10 53.6 56.6 -3.0 4 79 1977 2012 1963 1967 bottom-tenth 1978 11 54.0 57.4 -3.4 2 81 1977 2012 1941 1967 bottom-tenth 1941 12 54.1 57.3 -3.2 3 80 1941,1977 2012 1941 1967 bottom-tenth 18 49.9 52.9 -3.0 3 79 1941 2017 1964 1967 bottom-tenth 1964,1979 24 54.5 57.2 -2.7 2 79 1978 2012,2013 1968 1967 bottom-tenth 36 54.7 57.2 -2.5 2 77 1979 2013 1968 1967 bottom-tenth 48 54.9 57.2 -2.3 2 75 1980 2023 1966 1967 bottom-tenth 1964,1965,1966,1969 60 54.9 57.1 -2.2 1 74 1966,1967,1968,1981 2020 1967 1967 lowest 1966,1967,1981