Multiple states and territories are set to swelter into the new year as a heatwave grips much of northern Australia.

Parts of Queensland, the Northern Territory and Western Australia have been put on alert with temperatures forecast to be 8C to 12C above average.

The Bureau of Meteorology issued a heatwave warning for the NT, Queensland and WA while the south faces milder conditions.

An extreme heatwave warning was in place for the NT’s Tiwi district and for the Kimberley, Pilbara and North Interior districts in WA.

Temperatures in the remote towns of Marble Bar and Roebourne, in the northwest of WA, were expected to reach 48C on Sunday, with top temperatures at Marble Bar well above 40C for the next six days.

The heatwave comes a century after the town’s world record-breaking heatwave during the summer of 1923-24, when it recorded the longest run of days above 37.8C (100 degrees Farenheit).

The heatwave lasted 160 days from October 31, 1923 to April 7, 1924.

51 degrees

Marble Bar is unlikely to break its own record this summer, but the town heat gauge has been showing scorching temperatures higher than the bureau’s official readings, according to cattle station owner Wendy McWhirter Brooks.

“While we’re not going to do 160 days, it’s really hot at the moment, day before yesterday was 51 degrees,” she told AAP.

Most towns in the NT’s Barkly region were also expected to top the 40C mark.

A severe heatwave warning is in place for parts of Queensland, with severe thunderstorms predicted inland between Charters Towers and Roma, keeping emergency services on high alert.

But the thunderstorm threat has eased for Brisbane with severe storms no longer predicted for the city, which has not altered its official NYE program.

Queensland has already been hit by wild storms and floods that killed seven people over Christmas Day and Boxing Day.

The severe weather caused widespread power outages and more than 20,000 people in the southeast are still without electricity.

Further north, Cairns residents are being asked to conserve drinking water following severe flooding earlier in December, in the aftermath of ex-tropical Cyclone Jasper.

Mild weather is forecast for the southeast, including Sydney, on Sunday as Australia’s biggest city gears up for New Year’s Eve celebrations.

Tens of thousands of people are expected to flock to prime harbourside spots to watch the city’s famous fireworks.

-AAP