1991-2020 Degrees Fahrenheit 1 29.8 26.6 3.2 91 39 1936 1991 1952 1950 top-third 2 30.4 26.0 4.4 114 16 1936 1992 1952 1946 top-third 3 30.6 25.9 4.7 120 9 1969 1992 1952 1931 top-tenth 4 31.0 27.9 3.1 113 16 1969 1926,1931 1952 1944 top-third 1944,2016 5 34.6 31.4 3.2 117 11 1969 2000 1952 1944 top-tenth 6 38.8 35.8 3.0 120 8 1969 1961 1952 1931 top-tenth 1931,2002 7 42.5 40.3 2.2 113 15 1969 1992 1952 1944 top-third 8 45.3 43.8 1.5 109 19 1969 1931,1961 1952 1944 top-third 9 47.0 45.5 1.5 109 19 1969 1931 1952 1941 top-third 1968 10 47.6 46.1 1.5 111 17 1969 1931,2002 1952 1941 top-third 1926 11 47.8 45.9 1.9 116 12 1969 1931 1952 1941 top-tenth 1941,1988 12 46.0 44.9 1.1 104 24 1952 2013 1952 1941 top-third 2004,2006 18 40.8 41.9 -1.1 53 73 1979 2013 1952 1947 normal 1911 24 42.7 44.9 -2.2 20 106 1952 1935,1988 1952 1951 bottom-third 1907,1949 36 42.4 45.0 -2.6 6 118 1952 1989 1952 1950 bottom-tenth 48 42.7 45.0 -2.3 4 118 1952 2016 1952 1951 bottom-tenth 1900,1913,1951,1972 60 42.4 45.0 -2.6 2 118 1952 1935 1952 1951 bottom-tenth