The ute a father and son were in has been recovered from the water, after the pair tragically died when their car plunged into a river.

The father, a man in his 50s, was behind the wheel with his two sons when their car plunged into the Macdonald River in St Albans, north of Sydney, about 11.50pm on Wednesday.

WATCH THE VIDEO ABOVE: Sydney’s relentless rain takes tragic toll.

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One of the sons, 24, managed to escape and reach the riverbank.

The bodies of the father and the other son were found in the water about 11.20am on Thursday.

They are yet to be formally identified.

The Mitsubishi Triton the trio were travelling in was dredged from the river on Friday, with police divers feeling their way through the darkness to attach it to a waiting crane.

The tragedy comes as Sydney is experiencing an “extremely wet” spell, as described by Senior Meteorologist Angus Hines from the Bureau of Meteorology.

“Four or even five times the average monthly rainfall — that’s what we’ve seen so far in Sydney this month,” he said.

The city recorded its wettest August day in 18 years on Thursday, according to Weatherzone.

Warragamba Dam in the city’s outer south-west began spilling at 1pm on Friday, with minor flood warnings now in place for Putty Road, North Richmond, and Menangle Bridge.

Residents are urged to stay up to date with the latest flood and weather warnings on the BoM website.