Emergency services have been called out to a string of wet-weather incidents as the state's south-east continues to be drenched.

Rescue workers found a 67-year-old man dead inside his car on Tuesday after it was swept from a flooded causeway near Gympie on Monday night.

Police said it was believed the man travelled halfway across the bridge at Marys Creek Road before being swept away.

A spokesman said the man and his wife drove into the water about 6.50pm and got out of the car before the man got back inside to try to retrieve it.

An hours-long search was called off due to safety fears overnight but resumed at first light. The car was found shortly after and police later confirmed the man's body had been found inside the car.

The discovery came as a 41-year-old man continued his fight for life after a freak accident in Coorparoo, in Brisbane's inner-south.

Paramedics said a male car driver lost control in the wet on Deshon Street and mounted the footpath, hitting a jogger and landing in Norman Creek.

A police spokeswoman said the 48-year-old male driver was believed to have skidded coming round a corner, causing him to hit the runner and propel them both into the swollen waterway.

The car smashed through a barrier and became lodged on the creek's bed among trees and shrubs.

The driver climbed out of his vehicle but did not realise he had struck the jogger, according to paramedics.

It was only after passers-by spotted him in the creek that firefighters and paramedics were able to rescue the 41-year-old jogger.

He was rushed to the Princess Alexandra Hospital in a critical condition with significant chest and pelvic injuries plus signs of "post-immersion", a Queensland Ambulance Service spokeswoman said.

A hospital spokesperson said he was in the intensive care unit in a critical but stable condition.

The 48-year-old driver was transported to the same hospital with minor injuries.

Police were appealing for witnesses to the incident as Forensic Crash Unit were investigating.

- With AAP