Premier's urgent plea as 'very extreme weather event' bears down: 'No more'

Queensland premier Annastacia Palaszczuk has implored people in her flood-affected state to stay off the road and preserve drinking water as heavy rains continue to fall in southeastern parts of the state.

The death toll from flooding in the past five days across Queensland and into NSW climbed to seven overnight with another difficult 24 hours ahead.

"As you can tell if you're living in the south-east, there is a lot of rain around. It is non-stop," Ms Palaszczuk said.

Overnight a man died in the Brisbane suburb of Indooroopilly when his car became submerged. The 34-year-old tried to swim to safety but witnesses raised the alarm when he failed to surface.

"Can I say to everyone from the outset today, if you do not have to be on the roads, please do not be on the roads. We have a lot of water rising right across Brisbane and the south-east at the moment," Ms Palaszczuk said.

That sentiment was echoed by State Disaster Coordinator Steve Gollschewski at a press conference on Sunday.

"This is still a very dangerous situation," he told reporters.

"It's a rapidly changing environment. We're still seeing people getting caught up in this."

Police are still searching for a missing man who fell into the Brisbane River. The sole sailor, aged in his 70s, fell overboard from his vessel near the mouth of Breakfast Creek around 4.45pm on Saturday.

The search resumed at first light Sunday, involving water police vessels, general duties officers, coastguard personnel and volunteers.

The premier, police, and emergency services chief also implored Queenslanders not to engage in disaster tourism and move around to check out the flood affected areas.

"I don't want to see any more deaths. So please, please if you do not have to be out today, just stay at home, because this water is unrelenting at the moment," Ms Palaszczuk said.

"This is a very extreme weather event that we have at the moment."

Premier urges people to preserve drinking water

"Can I ask people in the south-east to conserve water at the moment. I know this might sound odd," the premier said.

However as emergency crews work to get treatment systems back up and running, residents are urged to be conservative with water use. It comes after there were problems with the Mt Crosby treatment plant during the flooding.

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"Please conserve your drinking water and we will be updating that as much as we possibly can," Ms Palaszczuk said.

Weather warnings span nearly 1000km of coast

Severe weather warnings in place on Sunday morning spanned almost 1000km of NSW and Queensland coastline.

Warnings are in place from Bundaberg in the Wide Bay-Burnett region of Queensland through to Port Macquarie on the NSW mid north coast.

As the rain-dumping system moves south, it is expected to ease on Monday but dangerous conditions will continue to persist.

Heavy rain and potential flash flooding are forecast from Kingaroy through to the NSW border on Sunday and intense falls are predicted for an area encompassing Hervey Bay, Yarraman, Toowoomba and Ipswich.

There is major flooding at Tewantin near Noosa and Picnic Point and Dunethin Rock on the Sunshine Coast, while flood warnings are in place for multiple waterways.

Brisbane Lord Mayor Adrian Schrinner on Saturday evening issued a warning for 16 suburbs along the Brisbane River, saying "several thousand properties" could be inundated.

In NSW, a severe weather alert for Sunday spans 450km from the Queensland border to Port Macquarie.

There is a risk of "life-threatening flash flooding particularly during Sunday afternoon and evening" across the Northern Rivers and Mid North Coast, in areas including Lismore, Grafton, Coffs Harbour and Dorrigo, said Gabrielle Woodhouse, Senior Meteorologist from the Bureau of Meteorology.

On Sunday and into Monday, the Northern Rivers and Mid North Coast are expected to see "widespread, high rainfall totals" exceeding 100mm, she said.

with AAP

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