Adelaide Hills on flood watch

Parts of the Adelaide Hills will be on flood watch on Friday with a significant rainfall expected across parts of South Australia.

The Bureau of Meteorology says showers will begin early and increase during the morning with falls of up to 50mm expected.

With catchments already quite wet, minor flooding is possible in the hills along the Torrens, Onkaparinga and North Para rivers.

Sandbags will be available from Mount Barker's State Emergency Service unit and Country Fire Service brigades in Gumeracha and Nuriootpa between 7pm and 9pm.