'Take action now': Urgent warning as massive rainfall and cyclonic winds hit state

People are being warned to “take action now” as wild weather lashing NSW and southeast Queensland is set to continue.

NSW and Queensland face another day of damaging waves, winds and rainfall, with weather officials warning of further flooding and coastal erosion.

A low-pressure system off the coast of southeast Queensland is bringing massive rainfall and cyclonic winds. It was also combined with a seasonal high tide, which washed away much of Byron Bay’s Main Beach on Monday.

The Bureau of Meteorology (BOM) warned on Monday that the coastline on NSW’s Mid North Coast was at risk of similar erosion, perhaps as far south as Newcastle.

The BOM urged residents of northern NSW to be ready for dangerous conditions on Monday evening and Tuesday morning, warning the weather would not relent until later in the day.

Wild weather is continuing on from the weekend, with senior BOM forecaster saying the rainfall is very rare.

About 475mm fell in the Gold Coast hinterland and more than 300mm drenched Upper Springbrook in the 24 hours to 9am Sunday.

“Just in the six-hour period ending roughly about 3am, [Springbrook] got 323mm so that’s a less than a one per cent chance we’d generally see that – so more than a one-in-100-year event,” he told the ABC.

NSW residents urged to take action now

Residents around the northern NSW town of Murwillumbah have been ordered to evacuate as record-breaking heavy rains continue to inundate the area as well as southeast Queensland.

The State Emergency Service has ordered anyone from Condong to Tumbulgum and surrounding areas to leave via the Tweed Valley Way.

An SES spokesperson said the region has been deemed "a high danger area" and about 1000 properties are affected.

The order comes after the Tweed River burst its banks near Tumbulgum on Tuesday, with minor flooding in the area. Flash flooding has closed roads and isolated small communities.

The Northern Rivers NSW SES also released an emergency warning to those in the most north-easterly region of the state, with a flood evacuation warning in place for South Murwillumbah and Tumbulgum.

Major flooding is expected at Tumbulgum around midday, with the high tide and moderate flooding forecast at Murwillumbah and Chinderah on Tuesday morning.

“The Bureau of Meteorology has predicted possible flooding for the Tweed River at South Murwillumbah, the Tweed River at Tumbulgum and surrounding areas,” the SES wrote on Facebook.

“As a result, businesses, residents and visitors to these areas should TAKE ACTION NOW to prepare for possible flood impacts.”

NSW SES is also warning people low lying properties may experience impacts due to flash flooding or riverine flooding.

Storm and flood impacts may also interrupt essential services such as electricity, phones, internet, water and sewerage.

“People in these areas need to closely monitor weather and road closures and make informed decisions early baed on individual circumstances,” the SES warned.

“Residents should monitor the situation as it is changing rapidly and be prepared to evacuate when instructed to do so.”

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The SES fears road access may be cut if floodwater inundates the area and people could become trapped or it may be too dangerous for SES to conduct rescues.

People in affected areas are urged to lift important possessions above the predicted flood height, take pets, warm clothes, medicine, insurance documents and other essential items.

The BOM has also issued flood warnings for Nambucca River on the NSW Mid North Coast while moderate flooding is expected at Bowraville and minor flooding predicted at Macksville on Tuesday.

SES crews receive thousands of calls for help

Southeast Queensland has copped more than 700mm of rain in three days, with a major landslide occurring at Mount Tamborine.

Queensland Police said Tamborine Mountain Road would be closed for a “significant” time after a landslide saw huge rocks and debris block road access.

A team of 300 SES workers from across Queensland had been sent to support the northern NSW teams, as well as resources from Fire & Rescue, NSW RFS and NSW Police to support the operation.

"They'll be out there working with the community, giving them information. If required, flood rescue. And in other instances, perhaps looking at tarping roofs, storm damage requests," NSW SES Assistant Commissioner Nicole Hogan said.

Queensland Fire and Emergency Services deputy commissioner Mark Roche said his crews had received about 1400 requests for help – mainly for leaking roofs and tarping and downed trees.

The wind and heavy rain was expected to ease, but he urged people to remain vigilant, stay out of floodwaters, drive with caution and turn back if they see a road or a bridge that's flooded.

"As we say, if it's flooded, forget it," he told ABC TV.

Ms Hogan said there had been more than 1000 calls for help in NSW in the past few days.

"There are no evacuations taking place at the moment. It is a warning for the community so that they can prepare to evacuate should the situation arise," she told ABC TV.

"There was significant rainfall within the Tweed area last night. We've also had significant weather in Coffs Harbour and Lismore."

Premier warns expect the unexpected

NSW Premier Gladys Berejiklian said weather experts had warned La Nina would have an impact all over over Australia.

"So we need to expect the unexpected," she told ABC TV.

"I'm hoping what we've seen in the last few days won't be repeated frequently over summer, but it could. Our weather experts tell us we're expecting conditions worse than what we've seen in quite a number of years."

with AAP

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