Premier Gladys Berejiklian has warned NSW residents to brace for the worst yet as the state continues to be lashed by torrential rain, prompting severe flooding in Sydney and the Mid North Coast.
She revealed to reporters on Monday that 18,000 people have so far been evacuated from their homes – 15,000 from the Mid North Coast and 3,000 from the Hawkesbury region.
Ms Berejiklian said warnings were now stretching south of Sydney with the Illawarra, south coast and the ACT subject to severe weather warnings.
The worst NSW flooding in 60 years
Urging residents against complacency, she warned the potentially-deadly conditions were far from over.
"Unfortunately we are not through the worst of it potentially. That is why we need to brace ourselves for what will be very difficult weeks and months of recovery," she said.
"This is an event which far exceeds what has occurred in the last 50 or 60 years."
As the Hawkesbury-Napean River system continues to swell, the premier said the town of Windsor was authorities' biggest concern. The Hawkesbury River is expected to reach 15 metres on Monday night.
There are currently 40 flood warnings and 20 evacuation orders in place.
Mr Berejiklian said it was "a miracle" no lives had been lost so far.
She offered support to those affected by the floods, many of whom battled the Black Summer bushfires just 12 months earlier as well as recent periods of drought.
"All of us are thinking of you," she said.
"I don't know anytime in our state's history when we've had these extreme weather conditions in such quick succession."
The Bureau of Meteorology said some areas have seen close to a metre of rain, with further rain expected to fall in those locations.
Superintendent Shane Cribb of Mid North Coast Police told the ABC thousands of homes had been flooded to varying extents.
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