1991-2020 Degrees Fahrenheit 1 46.7 57.4 -10.7 2 75 1965 1974 1958 1957 bottom-tenth 2 45.1 53.5 -8.4 1 76 1958 2017 1958 1957 lowest 3 44.6 50.8 -6.2 2 74 1978 2000 1958 1957 bottom-tenth 4 45.7 49.7 -4.0 6 69 1978 2000 1958 1957 bottom-tenth 5 46.3 50.8 -4.5 4 71 1973 2000 1958 1957 bottom-tenth 1978 6 49.0 53.3 -4.3 2 73 1977 2017 1958 1957 bottom-tenth 1960 7 52.6 56.6 -4.0 2 73 1977 2017 1958 1957 bottom-tenth 8 56.7 60.0 -3.3 3 72 1977 2000 1958 1957 bottom-tenth 1968,1975 9 60.1 62.6 -2.5 8 67 1977 2017 1958 1957 bottom-third 10 61.9 64.4 -2.5 6 69 1977 2012,2017 1958 1957 bottom-tenth 11 62.5 65.2 -2.7 3 72 1977 1999 1958 1957 bottom-tenth 12 62.5 65.2 -2.7 2 73 1977 2012 1958 1957 bottom-tenth 18 59.5 61.3 -1.8 8 65 1960 2023 1958 1957 bottom-third 24 64.6 65.2 -0.6 27 46 1978 2000 1958 1957 normal 2004,2010,2011 36 64.9 65.2 -0.3 34 37 1960,1977 2013 1958 1957 normal 1991,1992,2011 48 65.4 65.2 0.2 48 21 1978 1955 1952 1957 top-third 1952,2016 60 65.5 65.1 0.4 50 17 1977 1957 1958 1957 top-third 2001