1991-2020 Degrees Fahrenheit 1 25.1 32.5 -7.4 8 69 1977 2023 1948 1960 bottom-tenth 2 25.5 34.9 -9.4 1 75 1961 2002 1961 1960 lowest 3 32.0 38.7 -6.7 2 74 1977 2002,2016 1961 1960 bottom-tenth 4 37.8 43.3 -5.5 2 74 1977 2002 1961 1960 bottom-tenth 1981 5 43.8 48.6 -4.8 3 72 1977 2016 1961 1960 bottom-tenth 1970 6 49.1 53.2 -4.1 5 70 1977 2016 1961 1960 bottom-tenth 1964 7 52.6 56.7 -4.1 4 71 1977 2017 1961 1960 bottom-tenth 8 54.9 58.8 -3.9 3 72 1977 2017 1961 1960 bottom-tenth 9 55.6 59.4 -3.8 3 72 1977 2016 1961 1960 bottom-tenth 10 55.7 58.9 -3.2 7 68 1977 2016 1959 1960 bottom-tenth 11 53.6 57.5 -3.9 2 73 1977 2017 1951 1960 bottom-tenth 1941,1951,1968 12 52.0 55.6 -3.6 5 70 1968 2013 1959 1960 bottom-tenth 18 52.3 54.7 -2.4 15 58 1941,1964,1968 2017 1959 1960 bottom-third 1952,1971,1977,1982 24 53.5 55.5 -2.0 25 48 1964,1968 2013 1960 1958 normal 1946,1948,1958,1979 36 52.9 55.5 -2.6 8 63 1963,1965 2023 1959 1960 bottom-third 1959 48 53.3 55.5 -2.2 15 54 1964 2023 1959 1960 bottom-third 1943,1944,1979 60 53.2 55.5 -2.3 11 56 1965,1968 2023 1945 1960 bottom-third 1945