Premier Gladys Berejiklian has warned a "deep-seated, extreme" weather event which has brought record-breaking rain and floods to NSW may not ease up until late next week.
Heavy rain resulting in life-threatening flood conditions and the potential for dams to spill, gusty winds and dangerous surf has wreaked havoc across the state.
Speaking of the concerning weather conditions, Ms Berejiklian said the last time the state experienced major flooding, the weather event passed in just a few days.
"Unfortunately this will be a deep-seated, extreme weather event,” Ms Berejiklian said.
“It is unlikely the rain will stop until towards the end of next week."
This time around, the rain may linger until "Thursday or Friday" in some parts of the state.
"We hope those predictions are wrong," the premier said.
But she added the best predictions anticipate a "prolonged weather event" and warned the week ahead isn't going to be easy.
"I hate to say this again to all our citizens of the state but it's not going to be an easy week for us, but I know no matter what comes our way we will be able to deal with it," she said.
The premier has put already flooded and vulnerable communities on an emergency footing, and says more evacuations will certainly be ordered.
People living on the Mid North Coast, in the Hunter and Central Coast regions, in metropolitan Sydney, and in the catchment of Sydney's Warragamba Dam, must be on high alert, she says.
The premier says situation reports due by this evening will determine which communities will be ordered to leave their homes.
"Make sure if you are asked to evacuate you do so immediately. The window for evacuation is not a big one depending on where you live," Ms Berejiklian told reporters on Saturday.
"Some communities already have been advised to stock up and stay home."
'Unacceptable' acts could lead to thousands of rescues
Minister for Police and Emergency Services David Elliot said there have been over 500 rescues so far, saying that is "completely unacceptable".
"That's 500 specialist SES crews that have put their lives at risk because people have not heeded the warnings," Mr Elliot said.
"If the trajectory is correct and we keep going down this line we will look at 2000 flood rescues before Wednesday, when the majority of the storm should conclude."
He said the message was "very clear" — do not drive or walk through flood waters.
"We can't control the weather but we can control our behaviour," Mr Elliot said.
The minister urged people to look out for warnings and be prepared to evacuate if necessary.
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