Towns including Lismore, Tweed Heads, Murwillumbah, Byron Bay, Ballina and Casino are among those under flash flood warnings on Friday.
The Wilson River in Lismore, which reached a record 14.4 meters during a devastating flood in February, is again under flood watch.
The bureau said it expected flood levels to rise above the moderate flood stage of 7.2 meters by Friday evening or Saturday.
On Friday night, the suburb of Coachey Creek near Numinbach recorded 222mm in the three hours to 12.40am, while Chillingham in the Tweed Valley was hit with 171mm in the three hours to 12.48am.
The bureau’s Jane Golding said on Thursday that areas in the region will become even more saturated in the coming days.
“Some places have received almost a few hundred millimeters of rain in the last 24-36 hours and we are expecting more rain and thunderstorms,” she said.
“We expect areas to see 24-hour totals slightly above 100 millimeters but there will be a few spikes and some totals will be higher.”
Extreme weather led to the dramatic rescue of three people from flooding in Bingleborough near Dungag on Thursday.
Police Senior Constable Richard Hansen, using a rope as a safety line, waded into the water to reach the submerged vehicle.
After entering the water three times, the constable pulled the four-year-old boy and two women, aged 51 and 47, to safety. They were not injured, but were treated for shock.
Speaking at a press conference on Friday morning, Hansen said the “real drama” came after the evening news showed a vision of the rescue and his wife saw the lengths he went to to save the trio.
“She understands, it’s the nature of the beast,” he said.
Hansen said he placed a camera on the car to record the rescue so loved ones could see what he was trying to accomplish if things “went south.”
Detective Constable Wayne Humphrey said Hansen had shown “incredible bravery”.
“If Richie hadn’t done what Richie did, this press conference would have been a very different press conference,” he said. “He’s humble, he’s a fantastic village policeman and he saved the lives of these three people.”
Further north of the Northern Rivers, the Gold Coast also experienced flash flooding on Friday night. Inland areas of Upper Springbrook recorded 309mm overnight and Cloghirab recorded 292mm.
Heavy rain also forced a campsite in Helensvale, close to the Gold Coast’s popular theme parks, to be evacuated in the middle of the night.
Earlier this month the bureau announced a third La Nina The event took place in the Pacific Ocean.
The weather event should increase the likelihood of above average rainfall across eastern and northern Australia during the spring and coming summer season.
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