1991-2020 Degrees Fahrenheit 1 41.3 40.9 0.4 49 27 1972 2010 1949 1949 normal 2 34.6 34.4 0.2 47 29 1956 2010 1949 1949 normal 1981 3 29.8 29.2 0.6 52 23 2015 2010,2012 1949 1949 top-third 2013 4 27.7 26.1 1.6 62 12 1971 2012 1949 1949 top-third 1953 5 26.9 25.7 1.2 60 13 1971 2012 1949 1949 top-third 6 28.8 27.1 1.7 62 11 1971 2012 1949 1949 top-third 7 30.9 29.7 1.2 61 12 1971 2012 1949 1949 top-third 2020 8 34.1 33.2 0.9 61 12 1959 2012 1949 1949 top-third 2008,2020 9 37.5 36.8 0.7 60 13 1959 2012 1949 1949 top-third 2008,2020 10 40.3 39.7 0.6 58 14 1963 2012 1949 1949 top-third 11 42.0 41.8 0.2 54 17 1959 2012 1949 1949 top-third 12 -99 42.7 -99 -99 -99 1959 2012 normal 18 -99 37.7 -99 -99 -99 1971 2017 normal 24 -99 42.9 -99 -99 -99 1978 2017 normal 36 -99 43.1 -99 -99 -99 1965,1971 2023 normal 48 -99 43.0 -99 -99 -99 1971 2023 normal 60 -99 43.1 -99 -99 -99 1967,1971 2023 normal