Winds battering southern Australia over the last 24 hours have been so strong that spray from waterfalls south of Sydney has billowed up into the air.

Nearly a month's worth of rain has fallen on the city in 24 hours, and wind speeds have reached 120km/h (75mph).

The extreme weather has meant a rough ride on the city's ferries, and a high surf warning has been issued with waves expected to reach 5m (16ft).