Police have retrieved the body of an elderly woman from floodwaters in NSW’s Hunter Valley after her car was washed off a road on Wednesday morning, as gale force winds and heavy rain continue to batter Sydney and surrounding areas.

Divers near Maitland, north-west of Newcastle, found the body of the 86-year-old on Wednesday night.

The woman was from Gillieston Heights, south-west of Maitland.

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Witnesses watched in horror as a silver hatchback the woman was driving was swept from Cessnock Road in Maitland, into Wallis Creek, along with another car, about 9am Wednesday.

A second car was found nearby but police do not believe anyone was inside it when it was swept away.

A boat is washed up on the Gosford Waterfront on the Central Coast. Photo: Getty

NSW Police were initially told there were two women in the hatchback, but it’s now believed the driver was the only person in the car.

The death toll from the killer storm now stands at eight.

On Wednesday, a man died after his ute collided with a garbage truck in Galston, while an 87-year-old pedestrian was killed after being hit by a car at Gosford.

Two other people were killed on Wednesday afternoon after their cars collided in wet conditions on the New England Highway.

The town of Dungog near Newcastle has been rocked by the death of three elderly people, who drowned in their homes during flash flooding on Tuesday.

Emergency services have described the weather conditions as “devastating and relentless”.

By 8pm on Wednesday the State Emergency Service job tally was close to 12,000, including 123 flood rescues since Monday. There are still 8000 outstanding jobs waiting for assistance.

Flood waters enter the Parramatta ferry wharf in Sydney. Photo: Getty

The Insurance Council of Australia said it had received more than 19,500 claims so far and has declared a catastrophe in storm-hit areas.

SES Deputy Commissioner Steve Pearce said emergency crews were working hard in “horrendous” conditions to clean up the damage from the storms.

SES helicopters had been able to take to the air on Wednesday for the first time in 36 hours to survey the damage.

The NSW Government has declared 12 natural disaster areas where special assistance packages would be made available.

The declarations cover Dungog, Newcastle City, Maitland, Cessnock, Gosford, Warringah, Great Lakes, Lake Macquarie, Pittwater, Port Stephens, Singleton and Wyong.

On Thursday morning, the SES gave the all-clear for residents to return to the south Sydney suburb of Milperra after flooding concerns on the GeorgesRiver forced the evacuation of homes.

A car among debris of houses destroyed by cyclonic winds in Dungog. Photo: Getty

“Obviously the areas particularly impacted in the Hunter, Newcastle and across the Central Coast, we ask those communities to hang tough,” Premier Mike Baird said.

The SES said it expected winds as high as 100km/h and rainfall totals of up to 100mm in areas including the Illawarra, Sydney and the Central Coast for the rest of Wednesday.

Forecasters say the worst of the conditions has passed but a severe weather warning remains in place for the Illawarra region, south of Sydney.

Bondi Beach facilities remain under a layer of sand. Photo: AAP

Meanwhile, two people died late Wednesday afternoon after a car accident near Singleton.

Police say the crash on the New England Highway at Rixs Creek, northwest of Singleton, was a head-on collision between two cars.

The drivers of both vehicles died at the scene, police said.

On Tuesday, three people were killed during the storm event.

They were all believed to have been trapped in their residences after a flash flood swept through the town in the NSW Hunter region on Tuesday morning.

A cyclist powers through a flooded road at Bondi Junction, Sydney. Photo: AAP

They were believed to be living at a retirement village.

Police also rescued a mother and her baby from floodwaters in Maitland on Wednesday.

Mr Pearce said SES issued an evacuation order at 4pm Wednesday for parts of Milperra, saying residents who did not immediately leave were putting themselves at risk.

Mr Pearce said the order was based on modelling from the Bureau of Meteorology.

“Based on their modelling, the river is going to peak at a point where there would be inundation of these 200 properties,” he said.

“We can’t take the chance, seeing what we saw over the last three days, of anyone else being injured or put in danger.”

Emergency contact information

• Call NSW State Emergency Service for help with flooding or damage from storms on 132 500. 

• For life threatening emergencies, call 000 immediately. 

• For weather conditions visit the Bureau of Meteorology website.

Extraordinary photos here that show the true devastation in Dungog #SydneyStorm #nswstorms http://t.co/JsWhVy8Y4x pic.twitter.com/XT2L3r6LaT

— Lynton Grace (@LyntonGrace) April 22, 2015

#GRANVILLE: Residents forced to stay inside their homes as streets flood. Image via Cosimo Laporta. #NSWStorms #9News pic.twitter.com/i62qo30mW9

— Nine News Sydney (@9NewsSyd) April 22, 2015

Volunteers were seen off at the airport by @Jane_GarrettMP, Minister from Emergency Services #NSWstorms pic.twitter.com/ZkjuBQDcXw

— VICSES News (@vicsesnews) April 22, 2015

#nswstorms the O’Broen family from Gillieston Heights make it to Maitland so their little girli Cld get medical care pic.twitter.com/BeQf0wiAXy

— Damien Smith (@DamienSmith_7) April 22, 2015

this is what has been happening in NSW. to all out in the hunter #staysafe ❤️ #NSWstorms #australia pic.twitter.com/qwZmHN9zoX

— bwft ∞ (@britta_ox) April 22, 2015

– with AAP/ABC