Sydney floods hit 50,000 people around Australia's largest city, officials say 'event far from over' - In pics

Days of continuous rainfall have caused dams to overflow and waterways to break their banks, bringing a fourth flood emergency in 16 months to parts of the city of 5 million people.

About 50,000 residents in New South Wales, most in Sydney`s western suburbs, have been told to either evacuate or warned they might receive evacuation orders, up from Monday's 30,000, Reuters reported citing authorities.

Prime Minister Anthony Albanese, who returned to Australia Tuesday after a week-long trip to Europe, informed he would tour the affected regions on Wednesday.

"This event is far from over," New South Wales Premier Dominic Perrottet told reporters.

"Wherever you are, please be careful when you`re driving on our roads. There are still substantial risks for flash flooding," he added.

Some regions have received 800mm (31.5 inches) of rain since Saturday, eclipsing Australia's annual average rainfall of around 500mm (20 inches). Winds up to 90 km per hour (56 miles per hour) are forecast in several flood-hit places, raising the risk of falling trees and power lines.