Clean-up begins as deadly, damaging storms move on

A major clean-up is under way after wild weather battered the east coast, claiming one life and triggering evacuations and rescues.

Sydney and surrounds have borne the brunt of the inclement conditions, although major storm risks are expected to shift north after the weekend drenching.

Residents on parts of the city's northern beaches returned to their homes on Sunday after being told to flee to higher ground on Saturday night.

The evacuation orders forced locals and holiday makers near Narrabeen Lagoon out of their properties before warnings were downgraded in the morning.

Widespread deluges led to parts of the city's northern beaches and the Central Coast receiving up to 200 millimetres of rain in the 24 hours to 9am on Sunday.

Floodwaters at Narrabeen are expected to take several days to recede.

One man was filmed swimming laps on a flooded course at Palm Beach Golf Club on Sunday, while a bus driver in Warriewood struggled to finish their route as floodwaters inundated the aisle.

The NSW State Emergency Service conducted 25 rescues of people trapped in floodwaters, many in Sydney, as cars became submerged on inundated roadways.

Acting assistant commissioner Sonya Oyston said conditions were easing in Sydney, but a major clean-up remained.

"Our volunteers and emergency service partners have been out in force today assisting with fallen trees, damaged roofs and skylights, downed powerlines, and helping residents who have had water come into their homes through ceilings, under doorways and from blocked drains," Ms Oyston said.

At Great Mackerel Beach, an isolated outpost on the northern beaches that is accessible only by boat, a landslide damaged three homes and at least one person was injured.

Other regions such as Goulburn, in the NSW Southern Tablelands, were smashed by hail.

The storm system claimed the life of a woman on Saturday after a tree branch fell on her car on Macquarie Pass, southwest of Wollongong.

At least 1000 SES volunteers were on the ground on Sunday responding to weekend call-outs, with the busiest units in the south coast, Illawarra, Sydney and Hunter regions.

By early Sunday afternoon, crews had responded to more than 2300 incidents during the storm, mostly in Sydney and the surrounding area.

NSW SES spokeswoman Emily Barton told AAP rain had been experienced "far and wide" across the state.

Residents at Yarramalong and Dooralong on the Central Coast remain isolated due to flooding on the Wyong River and Jilliby Creek.

Ms Barton said clean-up efforts would continue in the coming days, with further severe thunderstorms forecast later in the week.

Warnings remain in place for hazardous surf on the east coast at beaches stretching from Newcastle to Batemans Bay, as well as the Eden coast.

The Bureau of Meteorology's Dean Narramore said the coastal trough that caused the storms stalled over the Central Coast, leading to repeated downfalls.

"That's why we just had storm after storm going over the same area, dropping 30 to 50mm each time," he said.

"After four or five of those, some places racked up to 200mm, which has led to quite a bit of flooding."

By Sunday afternoon, the storm risk shifted north, with people in parts of the Hunter and mid-north coast warned to prepare for heavy rainfall and severe thunderstorms.

Parts of Queensland also experienced significant rainfall, with Port Douglas receiving 109mm and more than 60mm dumped across the southeast.

More than 2500 properties in southeast Queensland were without power on Sunday afternoon.