A severe weather warning issued on Sunday for the entire coast will remain in place on Monday

This article is more than 7 months old

This article is more than 7 months old

Devastating storms have swept through eastern New South Wales, forcing flood evacuations and leaving tens of thousands without electricity.

Utility companies were on Sunday rushing to turn the lights back on for the more than 100,000 customers left without power.

Residents in low-lying areas near the Narrabeen Lagoon in northern Sydney were on Sunday night ordered to evacuate by the NSW State Emergency Service.

The SES said people risked being trapped without power and water if they didn’t leave the area.

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The south-west Sydney suburbs of Moorebank, Chipping Norton and Milperra were also ordered to evacuate.

Flooding along the Hawkesbury River could disrupt gas and water deliveries to the north-west Sydney towns of Richmond and Windsor, the SES said.

Emergency services have been swamped with calls since the deluge set in on Friday, while the extreme weather has caused transport chaos across Sydney.

“This wet and windy weather is really wreaking havoc on our roads today, with paramedics responding to five car accidents every hour since Friday night,” NSW Ambulance spokesman Giles Buchanan said on Sunday afternoon.

“We’ve responded to multiple trees that had fallen on to cars, trees into houses and units, and people trapped in cars in floodwaters.”

NSW Maritime said a number of boats had been sunk by the turbulent conditions at sea.

Anthony Clark (@AnthonyClarkAU) Incredible weather across Sydney. Upside down waterfalls at #Kurnell. #sydney #SydneyStorm #sydneyweather #weather pic.twitter.com/rrAQAfz5K2

Four people were hospitalised on Sunday afternoon after a tree fell on their car in the Sydney CBD.

A 16-year-old boy was also taken to hospital with suspected broken ribs after he was trapped between debris in waist-deep water for two hours in the Hunter region.

The teen was rescued by emergency services after falling into Allyn River while canoeing at about 9am on Sunday.

NSW Ambulance (@NSWAmbulance) Just after 1:30pm today NSW Ambulance were called to reports of a tree that had fallen on a car in the city. Paramedics treated 4 passengers in the car for neck pain and spinal precautions and transported them to hospital in stable conditions. #nswrain pic.twitter.com/WcgKqg0AOx

Utility company Ausgrid says more than 77,000 customers had lost electricity across Sydney, the Central Coast and Newcastle.

Endeavour Energy said a further 26,000 customers were without power in Sydney, the Blue Mountains and southern highlands.

“Crews are reporting extensive damage after very strong winds brought down power lines in many areas,” Endeavour Energy said.

Ausgrid (@Ausgrid) Our crews are working to repair more than 2000 hazards like fallen powerlines. 77000 customers are without power across Sydney, Central Coast & Newcastle.Crews will work through the night to get the power back on. Thank you for being patient in these trying conditions pic.twitter.com/33J26THBsc

A severe weather warning was issued on Sunday for the entire coast of NSW, and would remain in place on Monday.

The Bureau of Meteorology said the deluge could cause “life-threatening flash flooding” in the Hunter region, the Central Coast, greater Sydney, Illawarra and the Blue Mountains.

Sydney, the Central Coast and the Blue Mountains were soaked by between 200 and 400mm of rain from 9am Friday to 5pm Sunday.

The last time Sydney and the state’s coast had similar rainfall was mid-2016.

“But we’ve surpassed those figures and you have to go back as far back as 1998 to see totals like we’ll get,” a weather bureau spokeswoman said.

“It is uncommon to see rainfall rates as high as we have seen, up in the hundreds of millimetres occurring over consecutive days.”

NSW Police Assistant Commissioner Karen Webb urged drivers to take caution and avoid floodwaters.

“There are currently hundreds of calls for assistance, including trees, boulders or power poles down on to cars and homes, and across roads, as well as power outages and localised flooding impacting various roads and traffic lights,” she said.

Anton Blanchard (@antonblanchard) There used to be a road here somewhere. #SydneyStorm #NSWFloods #northernbeaches @smh @abcnews pic.twitter.com/fIuqO2V8GC

“I’m disappointed that I need to remind people to act responsibly and not to take risks in these types of conditions, especially when around floodwaters.”

Georgia Clark (@GeorgiaBClark) Torrential rain causing severe flooding here in Wentworth Point. Incredible aerial vision shows one car broken down in the middle of the floodwaters. #sydneyweather credit: Lee Williams pic.twitter.com/o6VlprviWZ

A king tide in Sydney also caused inundation in low-lying areas and there were risks of coastal erosion, Golding said. That was expected to hit Collaroy and other areas that were eroded by the 2016 storm surge. The Sydney Harbour buoy was recording waves of 5m, surging to 8m, and the seas were so rough that the buoy off Collaroy beach pulled free from its moorings.

The heaviest rain was recorded in the northern rivers region, where Kingscliff received 300mm in 24 hours. That rain was moving south down the coast, Golding said. Wentworth Falls in the Blue Mountains had received 200mm in the previous 24-hours, and parts of the mid-north coast received 250mm.

The town of Narrabri, 521km north-west of Sydney, went from “drought to flooding in a day”, the local SES said. Heavy rains made lakes of paddocks and flooded the train station.

Qutaiba Mehmood (@qutaiba_mehmood) From Fires to Floods, Welcome to Australia...!!!#SydneyStorm #AustraliaOnFire #ClimateChange pic.twitter.com/jOow22LXHN

In the Blue Mountains, a landslip affected what appeared to be part of the rain line at Leura, which according to witness Charly Race left the rails exposed.

“It was quite a loud noise,” Race told Guardian Australia. “My mum heard it – she came out running and screaming. We then saw all the mud coming through the back yard.

“A bollard that was holding up the track has come out. There is nothing holding them up. You can see them – there’s nothing under them.”

Calla Wahlquist (@callapilla) I’ve been sent some images of the land slip under the rail tracks at Katoomba. We reported on this earlier. Doesn’t look like that track will be taking trains any time soon. #SydneyStorm @GuardianAus @shelleymiranda @davidmunk pic.twitter.com/mwqh8fdCkm

A significant amount of rain fell in the catchment areas for Sydney’s water supply. WaterNSW storages were up 2% this week, and the Warragamba Dam catchment was forecast to receive 200mm of rain which will bring the dam level up to 70%. In the past week water levels in Warragamba have increased 0.9% to 43.8% full.

The Avon Dam was up 6.1% in the past week, the Blue Mountains Dam was up 9.7%, and the Nepean Dam was up 7%.

Meanwhile, locals on the NSW south coast were applauding the efforts of emergency services following the news that the massive Currowan Fire had been extinguished after burning for more than 70 days.

“As of 8pm tonight, the Currowan Fire burning in the Shoalhaven has been set to out,” NSW Rural Fire Service announced on Facebook on Saturday night.

The blaze burnt for 74 days and across 499,621 hectares, spanning right across the region and spreading to neighbouring councils including Eurobodalla, Wingecarribee and Queanbeyan Palerang.

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The weather bureau warned that the burned-out landscape and loss of vegetation had left the south coast vulnerable to landslips.

A video was posted online of a man driving his jetski past a McDonald’s down a flooded street in Tuggerah on the Central Coast.

It drew swift condemnation from the NSW police minister, David Elliott, who labelled the driver a “boofhead” and asked police to investigate.

“We have emergency services deployed during a difficult job under difficult circumstances, and for them to have to divert their resources … it’s just not good enough,” Elliott said.