SYDNEY, April 2 (Reuters) - Heavy rain brought flash flooding to Australia's largest city Sydney on Sunday, prompting rescues and residents to sandbag houses, as authorities warned of bad weather ahead.

Emergency authorities received 50 calls for assistance, mostly for sandbagging of properties and help plugging leaking roofs, from residents in Sydney, the capital of New South Wales state, due to Sunday's deluge.

It comes after Sydney in 2022 notched its wettest year in 164 years, as Australia's east coast endured a rare third straight year of the La Nina weather phenomenon, associated with increased rain.

A NSW State Emergency Service (SES) spokesperson told Reuters two people were pulled safely from cars that become stranded in floodwaters in Sydney's inner suburbs.

"Don't walk drive or ride through floodwater," the SES spokesperson said.

Outside Sydney, there were 27 calls for assistance in the Central Coast region, about 87 km (54 miles) north of Sydney.

The nation's weather forecaster issued a severe thunderstorm warning for parts of Sydney on Sunday, forecasting heavy rain and possible flash flooding, and warned of more rain for the city this week.