The severe weather battering NSW has shifted to the Hunter and mid-north coast, as damage assessments begin in areas surrounding Sydney that have been drenched for days.
Despite rain easing in Sydney, rivers will continue to pose flood risks in multiple areas as water continues to flow through the catchment on Wednesday.
In the Hunter and the Central Coast floodwaters are also rising, while many locations on the state's mid-north coast received heavy rainfall.
Premier Dominic Perrottet said 85,000 people were subject to evacuation orders and warnings on Wednesday morning.
The State Emergency Service had another busy night, conducting 21 flood rescues.
SES Commissioner Carlene York urged people to follow warnings and orders to evacuate.
"People have taken a risk and remained in those houses and then found out the risk is too great, and we have to go in and save those families," she said.
There have been 11 evacuation centres opened to support people ordered to flee their homes, including three new facilities in the Hunter region and on the Central Coast.
Flood Recovery Minister Steph Cooke said more than 500 people had sought refuge in the centres.
Meanwhile, authorities are closely monitoring the Hunter River at Singleton, where major flooding began on Wednesday, after the river reached a height of 13 metres in the early afternoon.
Further north, nearly 100mm of rainfall was recorded in less than six hours at Turners Flat, west of Kempsey.
The Bureau of Meteorology's Jane Golding said risks would remain even once the weather cleared, and flooding in the Hunter region was already worse than during downpours in March.
"(We are) starting to see some some fine weather on the horizon, but (it will) take a bit of time for the floodwaters to come down," she said.
Overnight, people in the Hunter community of Broke were cut off by rising floodwaters.
More than 6000 Hunter residents have fled to higher ground as rising water levels threaten their homes, with Singleton expected to cop a battering of heavy rain on Wednesday night.
The bureau says river levels in the town are likely to exceed the March 2022 flood level of 13.15 metres, and may reach 13.80 metres.
It is also is predicting severe weather to ease on Thursday as a low-pressure system tracks out to sea.
The SES has 1000 volunteers supporting isolated communities and has requested assistance from other states, while Prime Minister Anthony Albanese said a further 150 Australian Defence Force personnel would join the 100 troops already on the ground.
Queensland is also dispatching 40 frontline personnel on Thursday to assist residents caught up in the natural disaster.
Ms Cooke said damage assessments would begin in Sydney's west as floodwaters recede around the Georges River and Upper Nepean River.
However, residents should wait until they are given word from the SES that it is safe to return home, she said.
Mr Albanese and Mr Perrottet visited deluged parts of the Hawkesbury, a region that has endured four floods in the past 18 months.
The prime minister said applications for disaster recovery payments of $1000 for eligible adults and $400 for children would open from 2pm on Thursday.
Mr Perrottet said the focus remained on protecting lives and properties, but attention would shift quickly to support and recovery.
He admitted the distribution of recovery funding fell short of expectations during floods earlier in the year, but said the approval process has been improved to ensure money quickly reaches those who need it.
Opposition Leader Chris Minns said flood-affected residents previously had trouble accessing grants and the government needed to better inform people about the available supports.
"We want to make sure that those communities that are eligible for funds and grants actually get access to them," he said.
