A dangerous weather event that has delivered torrential rain across Sydney and prompted authorities to ask thousands of people to leave their homes was predicted to be "at its worst" overnight.
The warning came after a man died amid wild weather in Sydney, having fallen out of a kayak on the Parramatta River. Police tried to rescue the man but he died at the scene.
Hundreds of people have been rescued and NSW residents have been warned to avoid travel.
Once the system delivering the rain crossed the coast, probably before midnight, it would start to weaken, meteorologist Jane Golding said.
SES commissioner Carlene York said: "We are anticipating that these levels will rise above the last 18 months of flood levels."
"There are thousands of people that are affected by what we're looking at tonight," she said.
The key areas of concern were along the Hawkesbury, Nepean Georges rivers, according to Ms Golding.
Areas stretching from Newcastle to the South Coast and as far inland as Oberon are at risk, but especially western Sydney's flood-prone Hawkesbury-Nepean area.
Fears over the formation of an east coast low have materialised with Sydney, the Central Coast, the Hunter region, the South Coast and the Illawarra experiencing torrential rain, damaging winds, flash flooding, coastal erosion and riverine flooding.
Some areas have received more than 200 millimetres of rain with higher rainfalls of more than 350mm for parts of the Illawarra.
Daily rainfall in some places has exceeded their averages for July. In the 24 hours up to 9am Sunday, the highest total of 368mm was recorded at Brogers Creek just south-west of Wollongong.
Major flooding is occurring on the Hawkesbury River at North Richmond and may exceed the levels reached on three previous events — March 2021, March 2022 and April 2022.
The Windsor Bridge between Wilberforce Road and George Street is now closed, cutting off the direct link between northern Hawkesbury and Sydney.
It comes after the closures of the Richmond and Yarramundi bridges earlier on Sunday.
Just before 10am on Sunday, the Georges River at Liverpool Bridge peaked at 4.20 metres.
At Picnic Point it peaked at about 1:30pm and at Milperra Bridge it reached 4.15 metres at about 12:15pm before receding.
The Nepean River is now falling after peaking at 16.61 metres — exceeding the level reached in the March-April floods earlier this year.
However, major flooding is continuing at Menangle and moderate flooding at Camden and Wallacia.
The State Emergency Service (SES) has issued a number of evacuation orders including for parts of Camden, Chipping Norton, Georges Hall, Moorebank, Warwick Farm, Woronora, Bents Basin, Pleasure Point and Wallacia.
The heavy rainfall also caused the Warragamba Dam to spill at 2am this morning — much earlier than anticipated.
Water NSW said modelling showed the peak would be comparable to the major spill event in March last year.
In the past seven hours, the spillage rate has increased from 240 gigalitres per day to 500 gigalitres per day.
Emergency Services Minister Steph Cooke said the region was facing a life-threatening situation.
"We are now facing dangers on multiple fronts— flash flooding, riverine flooding and coastal erosion," she said.
"If you know your local community is prone to flooding then please be prepared to evacuate and at short notice.
"We have said this before, it is a rapidly evolving situation, so please continue to listen to the advice of the BOM [Bureau of Meteorology], listen to the advice of our emergency services organisations. Please, stay up-to-date."
Over the next 24 hours, the BOM is warning the east coast low will continue to develop, start to move south and closer to the Sydney and Hunter coast.
"For the Sydney area, we can expect more heavy rain today, particularly out towards the Blue Mountains and the Western Sydney area over the Hawkesbury-Nepean complex," meteorologist Golding said.
"And we can expect more heavy rainfall to affect the Central Coast and other parts of the Hunter district today … we will also see thunderstorms develop."
"We are also expecting to see an increase in the wind. So, that means trees down. We have already seen some damage from winds. Trees down, power lines down."
According to Assistant Commissioner Dean Storey, 137 flood rescues have taken place and SES members have responded to more than 3,000 requests for assistance.
"In many areas, it is still an evolving flood situation, and we may see more rain than what was originally forecast," he said.
SES Commissioner Carlene York said she was expecting her staff to again be kept busy over the next 24 hours.
However, she said she was disappointed in people continuing to drive through floodwaters.
"We had one example where a person was walking through floodwaters and got swept away," she said.
"They were unable to be rescued for an hour and had to hang onto a pole. It's extremely dangerous out there."
She also said a group of children were due to be rescued from a camp in the Wollondilly Shire south of Sydney.
"We have a number of youths isolated at a recreation camp in the Bargo area and we are putting in plans to evacuate them today," she said.
"They are safe at the moment."
Evacuation centres have been opened by local councils, but residents being told to evacuate are being urged to go to family or friends on higher ground.
NSW Police has also notified those affected of five centres operating across Greater Sydney: Cabra-Vale Diggers Club at Canley Vale, the Family and Community Centre at Narellan, Gymea Tradies Club, Richmond Club and North Richmond Community Centre.
Chipping Norton residents in Sydney's south-west are concerned about the location of their evacuation centre in Cabramatta — on the other side of the Georges River.
Trent Chalmers has lived in the area his whole life and is worried.
"If we got to get evacuated we can't get there. Unless they are going to take us by boat or fly us, which is stupid, how are we going to get there?"
Many people in the Blue Mountains and Hawkesbury were expecting to be cut off on Sunday, according to Federal Member for Macquarie Susan Templeman.
"We've already had one of our bridges close," she said.
"The locals around Richmond and North Windsor are saying the water is coming up very fast under their bridges."
Ms Templeton said the flooding would be devastating for a region that saw a record flood just three months ago and another in March 2021.
"This is another blow. People are already talking about leaving so that they don't have to go through this again," she said.
"We have had so many of these floods. I know people who had just moved back into their homes after repairing them."
ABC/AAP
