Wilmington, Delaware, Average Temperature Rankings, May 2022 1991-2020 Degrees Fahrenheit 1 65.8 63.6 2.2 65 11 1967 2004 2021 2019 top-third 2 59.4 58.8 0.6 60 16 1967 2019 2021 2019 top-third 3 55.0 53.6 1.4 65 9 1967 2012 2021 2019 top-third 2000 4 51.0 49.1 1.9 68 6 1978 2012 2021 2017 top-tenth 1976 5 47.0 46.0 1.0 63 11 1978 2012 2021 2020 top-third 1985,2019 6 46.4 44.7 1.7 65 8 1978 2012 2021 2020 top-third 7 46.1 45.0 1.1 62 10 1978 2012 2021 2017 top-third 8 48.2 46.5 1.7 65 7 1978 2012 2021 2017 top-tenth 9 50.6 49.0 1.6 66 6 1978 2012 2021 2017 top-tenth 10 53.4 51.7 1.7 67 5 1978 2012 2021 2017 top-tenth 11 55.6 54.1 1.5 68 4 1963 2012 2021 2020 top-tenth 2002,2020 12 57.1 55.6 1.5 68 4 1963 2012 2021 2020 top-tenth 2002,2006,2020 18 53.1 51.9 1.2 65 4 1979 2017 2021 2021 top-tenth 2012,2021 24 56.8 55.6 1.2 66 2 1978 2017 2021 2017 top-tenth 2012 36 56.9 55.5 1.4 63 1 1979 2022 2021 2022 highest 48 56.7 55.5 1.2 59 1 1966,1968,1970,1980 2019,2020,2022 2021 2020 highest 2019,2020 60 56.5 55.4 1.1 54 3 1967,1970 2020 2019 2021 top-tenth