1991-2020 Degrees Fahrenheit 1 27.9 36.5 -8.6 3 69 1959 2001 1959 1975 bottom-tenth 2 36.7 43.2 -6.5 1 71 1976 1963 1976 1975 lowest 3 44.4 49.6 -5.2 1 71 1976 2016 1976 1975 lowest 4 50.6 54.7 -4.1 1 70 1976 2016 1976 1975 lowest 5 55.1 58.1 -3.0 2 69 1992 2016 1951 1975 bottom-tenth 1951,2014 6 57.3 59.8 -2.5 3 68 1992 2016 1951 1975 bottom-tenth 7 57.1 59.7 -2.6 2 69 1992 2016 1976 1975 bottom-tenth 8 56.2 58.2 -2.0 5 66 1992 2016 1967 1975 bottom-tenth 1967 9 54.0 55.6 -1.6 9 62 1951 2012,2016 1967 1975 bottom-third 10 51.6 52.4 -0.8 25 46 2014 2012,2016 1975 1973 normal 1966,2009 11 48.4 49.3 -0.9 26 44 2014 2012 1975 1973 normal 1958,1986,1992 12 46.6 47.2 -0.6 36 34 2014 2012 1975 1973 normal 1961,2018 18 51.2 51.4 -0.2 39 30 2014 2016 1975 1973 normal 1963,1971,1984,1989 24 46.5 47.2 -0.7 25 43 1979 2017 1975 1974 normal 1968,1969,1977 36 46.2 47.2 -1.0 15 51 1979 2000 1972 1975 bottom-third 1962,1969 48 46.8 47.2 -0.4 35 29 1979 2001 1975 1958 normal 2009,2015,2016 60 46.5 47.2 -0.7 20 42 1979 2002 1975 1975 bottom-third 1959,1964,1975