NSW and Queensland are facing another day of damaging waves, winds and rainfall, with warnings of further flooding, possible evacuations and coastal erosion.

A low-pressure system off the coast of southeast Queensland has brought massive rainfall and gale-force winds, which combined with a seasonal high tide to wash away much of Byron Bay’s Main Beach on Monday.

A severe weather warning has been issued for the NSW northern rivers and mid north coast.

Heavy rain has continued overnight in the Tweed catchment and will continue.

The State Emergency Service has now issued a flood evacuation warning for south Murwillumbah, Tumbulgum and Tweed Valley Way and surrounding areas after the the Bureau of Meteorology predicted possible flooding for the Tweed River.

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

Further rises are possible if the rain intensifies again in the next few hours.

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Minor flooding is occurring along the Nambucca River at Bowraville, with moderate flooding expected on Tuesday morning.

Minor flooding is possible at Macksville later on Tuesday morning.

The SES says electricity, phones, internet, water and sewerage could be interrupted, and people in those areas need to closely monitor the weather and road closures.

It says residents should monitor the rapidly changing situation and be prepared to evacuate when instructed to do so.

A flood evacuation order would be issued by the NSW SES if and when evacuations are required.

It warns once floodwater begins inundating the area, roads may be cut, trapping anyone who stays behind.

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“If you remain in the area after this time, you may become trapped and it may be too dangerous for NSW SES to rescue you,” the SES warned in a statement on Tuesday.

NSW SES Assistant Commissioner Nicole Hogan said there had been more than 1000 calls for help 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.

Conditions are expected to ease later on in the morning but there is the possibility of thunderstorms.

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

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“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,” Ms Hogan said.

Southeast Queensland received a reprieve on Monday afternoon after earlier experiencing tropical cyclone-like conditions. The damaging winds and heavy rainfall eased up by evening, but surf and tide conditions are still dangerous.

The damage to storm-lashed beaches could be lasting, with Surf Life Saving NSW warning the giant waves could create new, permanent rips at beaches previously considered to be safe.

Sites in NSW’s Northern Rivers District had about 400mm of rain in just a few days, and some locations near the Queensland-NSW border were inundated with 180mm of rain on Sunday.

AAP

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