Weather history and climate summary information is available for the following locations:
- Dover
Warmest September Days
The warmest September days in Delaware are:
| Dover, Delaware | 1943 | 97.3°F |
| Dover, Delaware | 2010 | 96.4°F |
| Dover, Delaware | 1970 | 95.9°F |
| Dover, Delaware | 1953 | 95.4°F |
| Dover, Delaware | 1980 | 95°F |
Coldest September Days
The coldest September days in Delaware were:
| Dover, Delaware | 1963 | 39.4°F |
| Dover, Delaware | 1956 | 39.4°F |
| Dover, Delaware | 1962 | 40.3°F |
| Dover, Delaware | 1992 | 41°F |
| Dover, Delaware | 1974 | 41°F |
Wettest September Days
The wettest single days in September occurred:
| Dover, Delaware | 1999 | 4.6 inches |
| Dover, Delaware | 1985 | 4.3 inches |
| Dover, Delaware | 1992 | 3.2 inches |
| Dover, Delaware | 2006 | 2.8 inches |
| Dover, Delaware | 1989 | 2.6 inches |