South west Victoria has been hammered by storms.

The Bureau of Meteorology issued a severe thunderstorm warning for Portland, Warrnambool, Casterton, Hamilton and surrounding areas on Saturday.

The bureau warned damaging winds, heavy rain, large hailstones and “life-threatening” flash flooding were likely.

It’s reported 30 millimetres of rain fell in less than 15 minutes in Warrnambool.

Some 50mm of rain fell within that hour.

The SES received dozens of calls for help.

The severe weather warning has since subsided, but rain continues to fall across the state.