By Jack Gramenz and Luke Costin in Sydney

The combination of two major storm systems has brought intense rain to NSW and southern Queensland, creating havoc as people are urged to stay indoors while the weather makes it dangerous to travel.

Train services face major delays because of damaged equipment at Redfern station in inner Sydney, while dozens of flights in and out of the city’s international and domestic airport terminals have been cancelled.

Power was also cut to a major city-centre court complex after the rain affected local electricity infrastructure.

Transport for NSW has advised people to delay any non-essential travel on the roads and recommends boaters remain ashore as the dangerous storm system travels along Australia’s eastern seaboard.

A severe weather warning is in place along the NSW coast from Morisset, south of Newcastle in the Hunter, to Bega on the South Coast and extending west to the Central and Southern Tablelands past Oberon and Goulburn.

“Through this region we’re looking at heavy to locally intense rainfall,” the Bureau of Meteorology’s Angus Hines said on Friday.

“We also anticipate damaging wind gusts … exposed places could reach 90km/h,” he said.

Severe thunderstorms are possible from the Queensland border south to Wollongong and west to Griffith and Cobar.

Minor to major flood warnings are in place on the Hawkesbury, Nepean, Myall, Macquarie, Lower Hunter, Georges and Woronora Rivers, with moderate to major flooding likely along the Colo River.

The NSW State Emergency Service had 47 warnings in place early on Friday afternoon, including a watch-and-act notification for a region from Sydney to the Blue Mountains and south to Batemans Bay.

People across the area were advised to stay indoors because of heavy to intense rainfall.

There had been 90mm of rain at Taree, on the mid-north coast, since 9am on Friday, while further north at Port Macquarie nearly 84mm had fallen.

At Lismore, in the Northern Rivers region, an elderly man taking his chances with flooded roads on the way to visit his wife in hospital ended up stuck with water up to the roof of his four-wheel drive.

The river had risen quickly overnight, according to retired lawyer Keith Graham, who swam out to save the man.

“I have no idea what he was thinking,” Mr Graham told AAP.

It was one of several car rescues in recent days and followed the death on Wednesday night of a 71-year-old man who appeared to drive into a swollen creek in Logan, southwest of Brisbane.

Authorities have issued warnings for parts of southwest Queensland with river levels expected to rise above a moderate level at Charleville later on Friday because of multiple days of heavy rainfall.

Floodwaters are not expected to exceed levee levels at their peak, leaving the town protected from inundation.

A flood watch is also in place for southern inland rivers.

The rain is expected to shift further south into Saturday, easing before the weather system moves over the Tasman Sea.

But flood dangers will linger for several days.

Warragamba Dam – which serves as Sydney’s main reservoir and was 96.3 per cent full – is likely to spill on Monday, Water NSW chief executive Andrew George warned.

“We require about 90mm of rain to fill Warragamba Dam … we’re expecting 100mm to 150mm,” he said.

An inland low and coastal trough joining forces over NSW are driving the deluge.

The ongoing intense downpours would drive “dangerous and life-threatening flash flooding” from Friday evening, the SES warned.

In Sydney’s city centre, 111mm of rain fell in the 24 hours to 9am on Friday, followed by a further 21mm over five hours.

During a period of 24 hours, the SES responded to 823 incidents, including seven flood rescues.

There had been no reports of serious injuries or major damage, the agency said in a statement on Friday afternoon.

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