Thousands of Greater Sydney residents have fled their homes as flooding worsens and 69 evacuation orders were in place on Monday morning.

Parts of Sydney, Illawarra and Hunter regions were hit with another 100 millilitres of rain overnight after flash flooding at the weekend. NSW SES performed about 100 rescues overnight and has warned residents to evacuate or prepare to bunker down ahead of more dangerous weather.

“We’ve issued about 70 evacuation orders, mostly in the Hawkesbury-Nepean area. We’ve got another 66 communities on prepare-to-evacuate,” NSW SES Deputy State Duty Commander Ashley Sullivan said on Monday.

“What that means is that large communities have already been asked to evacuate because of the flood threat and there’s a large part of the communities that potentially are at risk in the coming days.”

The Bureau of Meteorology senior forecaster Jonathan Howe said more rain was on the way.

“We are still seeing plenty of moisture still off the coast of Sydney and so that is still pumping a lot of moisture onto the coast so the rain threat isn’t over just yet, even though the east coast low has very much weakened over the coast,” he said.

Sullivan said SES was concerned for Monday afternoon when rain and wind was expected to pick up.

“We’re expecting more weather in the next 24 to 48 hours and that’s not a good sign,” he said.

“We are expecting strong winds and heavy rain. We’ve already seen the rivers rise much quicker than what they would normally rise, because of the levels of saturation in the ground.

“That is meaning things are happening quicker, rivers are rising quicker, evacuation orders and warnings are happening quicker and more frequent than what we did expect.

The SES has told residents in Sydney, the Hunter, the Illawarra and the Blue Mountains to prepare for strong winds on Monday afternoon.

“If we do get the strong winds, that’s going to cause a lot of concerns for the trees, the levels of saturation in the ground. It won’t take a strong wind at all to start blowing them over so consider where you park your car and, like I said, stay off the roads if you don’t need to travel.”

The SES has conducted more than 200 flood rescues and answered thousands of calls for help since the emergency began on Saturday. One person has died.

The majority of rescues have been people attempting to drive in flood waters, which the SES warns against.

The hardest hit areas at the weekend were mainly in the Hawkesbury Nepean region, which faces its fourth flooding event in 18 months.

The only remaining direct connection between the northern Hawkesbury and Sydney, the Winsdor Bridge, flooded on Sunday and the BoM predicted levels could peak at 13.30 metres.

The bridge was designed to be “flood-proof”. It was also closed during the floods in April.

Many roads and bridges have been affected by flash flooding. Find the latest evacuation orders here.

NSW SES has urged people to call 132 500 for emergency assistance. If your life is at risk, call Triple Zero (000) immediately.

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