NSW communities are warned to 'be prepared' amid flash flooding concerns

People have been taken by surprise by flooding in Queensland and northern New South Wales, but people further south have been given some time to prepare as the weather cell approaches.

SES Flood Rescue Operator Adam Jones says the next places the severe weather system is expected to hit is between central NSW all the way down to Bega on the South Coast.

"We're asking all of the community to prepare their properties and prepare their plans as well," he told A Current Affair host Tracy Grimshaw.

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He said soil has been completely saturated and all river systems and dams are now full across the east coast.

"So even if you're not in the heart of where this storm hits, we could be seeing flash flooding just from a small amount of rain, up and down the coast," Mr Jones said.

He said it's not just a case that it might happen and there is a system forming on the coast that will hit land.

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"As we've seen up north these events take people by surprise," he warned.

Mr Jones said his team are asking that everyone throughout NSW starts preparing for what is predicted to be "an unprecedented rain event".

He said there's already a flood warning out for the Hawkesbury Valley region and warnings are coming through for the whole South Coast.

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"We are asking our community to get ready now," Mr Jones said.

Farmers are being advised to move stock to higher ground.

He said it was important that people consider whether their travel was essential and suggested checking whether routes were still open.

He said it was vital that people turn around if they are met with floodwaters when travelling.

"We are asking people to limit their travel," he said.

"We need to make sure that if the event does hit down here, it's as minimised as possible and that's by … making smart decisions now, preparing your home or your property or your business.

"That includes moving stock up to higher ground, that includes … making sure your gutters are clear, clearing any debris from around your home … (and) tying down any loose items."

For people in south-east Queensland impacted by flooding, there is help available.

In an emergency, phone your local SES unit on 132 500.

In life threatening situations call triple zero immediately.