Weather history and climate summary information is available for the following locations:
- Huron
- Rapid City
- Sioux Falls
- Watertown
Warmest October Days
The warmest October days in South Dakota are:
| Rapid City, South Dakota | 1963 | 93.9°F |
| Huron, South Dakota | 1997 | 93.9°F |
| Rapid City, South Dakota | 1953 | 93°F |
| Rapid City, South Dakota | 1975 | 91.9°F |
| Huron, South Dakota | 1989 | 91.9°F |
Coldest October Days
The coldest October days in South Dakota were:
| Rapid City, South Dakota | 1991 | 0.1°F |
| Rapid City, South Dakota | 1997 | 6.8°F |
| Rapid City, South Dakota | 1993 | 7°F |
| Huron, South Dakota | 2002 | 8.1°F |
| Watertown, South Dakota | 1991 | 8.2°F |
Wettest October Days
The wettest single days in October occurred:
| Rapid City, South Dakota | 2007 | 4.8 inches |
| Sioux Falls, South Dakota | 1973 | 4 inches |
| Watertown, South Dakota | 1984 | 2.2 inches |
| Sioux Falls, South Dakota | 1998 | 2.2 inches |
| Rapid City, South Dakota | 2006 | 2.2 inches |