WHAT WE KNOW:

• Major flood warning for the Tweed River
• 40,000 Tweed residents affected, 17,000 properties
• 3 evacuations centres in Tweed, at Murwillumbah, Kingscliff and Banora Point
• Major flooding expected tonight at Murwillumbah with peak at high tide around midnight
• Evacuation orders in place at South Murwillumbah, Condong, Tumbulgum, Chinderah, Fingal Head, Kingscliff, Bilambil, South Tweed, West Tweed.

UPDATE 10pm: A NEW major flood warning has been issued for the Tweed River as evacuation centres begin filling up. 

In a statement issued at 9.35pm tonight, NSW SES Richmond Tweed region incident controller David Monk said between 350mm and 480 mm of rain had been recorded in the past 24 hours in the middle and upper reaches of the Tweed River valley, with significant river rises occurring.

"Further heavy rainfall is forecast over the next nine hours which could produce further river level rises," Mr Monk said. "The situation is being closely monitored and revised predictions will be issued if necessary. "

The Bureau of Meteorology has predicted the Tweed River will reach 5.70 metres at the Murwillumbah gauge on Friday morning, and 2.00 metres at the Barneys Point gauge at Chinderah by Friday morning, with renewed rises possible with the high tide.

This will cause major flooding on the Tweed River. The current river heights are: Murwillumbah gauge is 5.39 metres Barneys Point gauge is 1.42 metres.    

MURWILLUMBAH:   At this predicted height there is a high probability that the South Murwillumbah levee wall (4.85m) will be over-topped, and may flood the lower levels of about 176 houses (mostly elevated).

Water levels are also expected to enter the lower levels of elevated houses in Bray Park.

CHINDERAH:

At the predicted height of 2.00m, most of Chinderah is inundated and water starts to enter the low-lying areas of Kingscliff. Some houses in Chinderah will have water over their floors and access to many areas is only possible by boat.

Should the river reach 2.55 metres at Barneys Point the floodway will cross the Pacific Hwy closing it to light traffic; which will mean there will be no access between Tweed Heads and Kingscliff with no alternative route available.

EVACUATION CENTRES

Meanwhile, Tweed MP Geoff Provest said the Kingscliff TAFE evacuation centre was preparing to accept up to 200 additional residents tonight, as police evacuate low-lying caravan parks at Chinderah.

Already, 30 people are at the Kingscliff centre, while 40 people were at the Murwillumbah evacuation centre.

A third evacuation centre has been opened at Banora Point High School, where 12 people are bunkering down for the night. Mr Provest urged residents to take their own bedding with them if possible.

He said strong winds and 5m swells would also affect the region tomorrow.

The NSW SES recommends the following actions:

* If river levels continue to rise residents in low lying areas that may become isolated, need to consider the impact of potential flood isolation on their work, family & educational commitments. * Keep in contact with your neighbours. * Farmers on low lying land close to rivers and creeks are urged to monitor livestock, pumps and other equipment. * If your property is at risk of inundation, please raise moveable items, such as furniture, as high as possible onto benches or tables, placing electrical items on top. * If you are advised by an emergency services officer to evacuate, please do so. * Secure outside belongings and before leaving; turn off the power, water and take essential medicines and clothes with you. * Never drive ride or walk through floodwater.   For emergency help in floods and storms, call the NSW SES on 132 500

EARLIER AT 8PM:

THOUSANDS of residents across the Tweed have been ordered to evacuate their homes and thousands more are isolated, as ex-tropical Cyclone Debbie continues to wreak havoc across the region.

As of 9pm tonight, three evacuation centres had been opened across the Tweed, including at Murwillumbah's Sacred Heart Catholic Church, Kingscliff TAFE and Banora Point High School as communities brace for a sleepless night with heavy rain continuing to fall.

The NSW SES Richmond Tweed command has ordered residents at South Murwillumbah, Condong, Tumbulgum, Chinderah, Kingscliff, Fingah Head and low-lying areas of Bilambil, South Tweed and West Tweed to evacuate, with the Tweed River expected to peak at the high tide around midnight tonight.

ROLLING COVERAGE: Evacuation orders in place

Figures from the Bureau of Meteorology show more than 417mm of rain had fallen in the Tweed River catchment area in the 24 hours to 5pm, with major flooding at Murwillumbah where the river is expected to hit 5.6m later tonight.

The Tweed River at Chinderah (Barneys Point) is expected to exceed the minor flood level (1.3m) around 8pm Thursday. The river level and may reach around 1.9m later tonight with moderate flooding on the high tide. Further rises are possible.

Across the region, evacuations have also been ordered at Lismore, where the Lismore River is expected to break the levy wall at 11m.

Tweed MP Geoff Provest, speaking from Sydney where he is being briefed by various departments, said about 50 residents were at the Kingscliff TAFE evacuation centre tonight, with about 230 people contacting the centre since this morning.

"The real crunch is going to come later this evening," Mr Provest told ABC Radio.

"We've got a 1.5m high tide and that will meet the storm turge coming down the river."

Mr Provest said the SES had taken around 862 calls for assistance and completed 36 flood rescues, with around 40,000 people or 17,000 properties currently affected.

"On the ground we have around 73 active SES teams working very hard but really at this moment we are really encouraging people to stay in place and if they are threatened ring the SES or Triple 0," he said.

"I think it is going to get a lot worse tonight, we have four helicopters at Lismore standing by. It is going to be a major event tonight, I believe."

Mr Provest thanked local volunteers who had "put their own life at risk to help the wider community".

"There's a great feeling of comeraderie and assistance from the wider community," he said.

Elsewhere, several communities have been isolated, including at Uki, where both bridges in the town are inundated and downed power lines have left more than 450 residents without power.

Uki resident and former Tweed mayor Barry Longland said he had never seen the river rise so quickly in his 17 years in the area.

"It's the worst I've witnessed in the 17 years I've lived in the village," Mr Longland said.

"It's pretty wild out here. Everyone is quite amazed at how quickly it has happened and the extent of the river rising, people haven't seen it rise so quickly.

"We've had about 400mm of rain - that's 16 inches - in a very short period of time and the ground is already saturated."

At South Murwillumbah, floodwater had breached levy banks, with reports on social media suggesting the town's main bridge was in threat of going under.

A post to the Murwillumbah Matters Facebook page said floodwater was reaching businesses.

"Just went for a walk down across the main bridge in town," Tracie Ducat wrote at 7.24pm.

"The river has well and truly broken its levee banks on the south side and the water level is at about 30cm below the bottom of Beaurepaires glass window of showroom, two-foot below the veranda floorboards of Phil Taylor's house there on the corner; wheelie bins are floating down River Street.

"To those poor flooded South Murwillumbah businesses - the organic butchers, the clothing alterations shop and more: wishing you guys all a swift clean up with lots of assistance to get everything back to working order again."

Banora Point Fire Station also posted to Facebook to let people know an "evacuation centre (has been) set up at Banora Point High School, 2 Eucalyptus Drive".

Another posting on Kingscliff Matters Facebook page from Leisa Shore at arouind 7.30pm reads: "We've been evacuated from Fingal. King tide tonight. Police come to door, we had 20 mins to get our stuff and go. Be safe everybody."

Earlier, residents at Tumbulgum - which has since been cut off - were preparing for inundation.

Fingal Head Community Association president Helen Twohill said she believed most people won't evacuate the peninsula as the flood water rises because it's too dangerous.

"The problem is you must drive through flood waters to get evacuated," Ms Twohill said.

"A lot of people are just staying put."

If you need help SES assistance call 132 500 or in an emergency call Triple 000.

Most schools are expcted to be closed tomorrow.

To check road closures, visit myroadinfo.com.au

* In emergency, phone the SES on 132 500.