Hail stones the size of a ten-cent piece have been reported in the Barossa Valley as thunder storms sweep across the state.

The hail blanketed the Barossa Valley, turning the region into what looked more like a snowfield rather than a wine region.

Storms have brought flash flooding to some parts of Mt Barker and the Barossa, with localised heavy falls of up to 40mm across those areas.

Rowland Flat in the Barossa recorded a whopping 24mm in just 30 minutes, while Mt Adam received 35mm in just one hour.

The Bureau of Meteorology has warned the storms could still bring damaging winds and heavy rainfall that could lead to flash flooding.

Click here for the latest warnings for South Australia from the Bureau of Meteorology

Children take advantage of the conditions and try to make 'snow' angels in the ice in the Barossa Valley. Photo: 7News.