1991-2020 Degrees Fahrenheit 1 45.8 51.6 -5.8 2 74 1953 2020 1953 1982 bottom-tenth 2 40.5 47.0 -6.5 1 75 1983 2020 1983 1982 lowest 3 38.1 42.9 -4.8 5 71 1964 2020 1980 1982 bottom-tenth 4 34.9 38.2 -3.3 16 60 1964 2020 1979 1982 bottom-third 2008 5 31.8 33.9 -2.1 30 46 1984 2018 1982 1981 normal 6 29.8 31.2 -1.4 30 44 1979,1984 2018 1982 1981 normal 2010 7 29.8 31.0 -1.2 32 42 1973 2018 1980 1982 normal 8 31.1 32.5 -1.4 30 44 1973 2018 1980 1982 normal 9 33.7 35.1 -1.4 31 43 1973 2018 1980 1982 normal 10 36.7 37.9 -1.2 32 42 1973 2018 1980 1982 normal 1972,1997 11 39.1 40.3 -1.2 32 42 1973 2018 1980 1982 normal 1972 12 40.5 42.0 -1.5 28 46 1973 2018 1980 1982 normal 1955,1969,1991 18 36.8 38.4 -1.6 27 45 1993 2018 1980 1982 normal 24 40.9 42.0 -1.1 35 37 1993 2018 1980 1982 normal 1959,2008 36 41.5 41.9 -0.4 48 22 1975 2018 1982 1983 top-third 48 41.1 41.8 -0.7 44 24 1976 2019 1982 1959 normal 1959 60 40.4 41.6 -1.2 27 39 1977 2020 1981 1982 normal 1962,1981,1984