Temperature record shattered as historic heatwave smothers states

A remote South Australian town has recorded its hottest day on record as a "historic" heatwave pushes temperatures near 50 degrees across several states.

A remote South Australian town has recorded its hottest day on record as a historic heatwave pushes temperatures near 50 degrees across several states.

Effects of the ex-tropical cyclone Luna and a high-pressure system in the Tasman Sea are creating a prolonged heat mass over South Australia, Victoria, New South Wales and Queensland.

The system caused temperatures to soar, Australia Day events to be cancelled in Adelaide, and a heightened bushfire threat across Victoria.

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Ceduna, a small town about 780km from Adelaide, had its hottest day on record after it reached 49.5 degrees today, beating its previous record of 48.9 degrees in December 2019.

The Bureau of Meteorology's Dean Narramore said the record-breaking temperature could nudge higher still.

Wudinna Airfield recorded the hottest January day on record at 48.4 degrees, which was equal to the temperatures recorded in December 2019.

The rest of the affected states reached past 45 degrees.

"Just huge areas of inland Australia, pretty much at and above 44 or 45 degrees today," Narramore said.

He added the high temperatures were unusual for this time of year.

"That's pretty record-breaking. It's a very unusual, record-breaking heatwave, and in some way, historic heatwave for parts of inland and south-eastern Australia," he said.

Several Australia Day events were cancelled in Adelaide as the mercury hit 45 degrees.

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The Aus Lights on the River and the evening fireworks have been cancelled because of the heat; usually about 25,000 spectators take part in the annual event.

The mercury is forecast to remain above 40 degrees tomorrow, with the city of churches set to experience maximum temperatures above 30 degrees all the way until Saturday.

Parts of Victoria are also set to swelter, with Melbourne reaching 44 degrees tomorrow, and parts of the state getting close to 50 degrees.

Mildura in Victoria's north-west is expected to have temperatures of 48 degrees tomorrow, which would break the town's record of 47.2 degrees, set back in 1939.

Victoria's heat is intensifying the threat of bushfires that have been burning across the state all weekend, with fires in several areas of the state burning out of control.

Residents in parts of the Otway ranges, the Dargo area and near Walwa are being told to prepare for an evacuation as fire conditions continue to be severe.

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Brisbane will also see hot weather this week, after a top of 36 degrees today, while Canberra will soar to 42 degrees on Wednesday.

Emergency services were forced to issue an urgent reminder not to leave children, pets or older people unattended in vehicles after paramedics responded to 11 cases of children locked in hot cars across Melbourne and regional Victoria.

"The temperature inside a vehicle can double and become deadly within minutes," Ambulance Victoria Director of Emergency Management Dale Armstrong said.

"It is particularly dangerous for children to be left inside vehicles, as a child's body temperature rises three to five times faster than an adult."

"If you are on the coast you will see a bit of relief coming through on Tuesday, but that does mean we are expecting some very hot days on the way," the Bureau of Meteorology's Jonathan How said.

"Anywhere inland, unfortunately relief only comes at the end of the week, even into next weekend, so we are looking at a run of five to seven days above 40 degrees and some locations even above 45 degrees, even pushing towards 50 degrees."

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Narramore said there will likely be more records broken this week as the hot weather system moves across to Victoria, New South Wales and then Queensland.

"We could see many locations in eastern South Australia, western and south-western Victoria break January record and a few places could also have their hottest day on record," he said.

While Australians on the east coast prepare to sweat through the week, those in the west are dealing with the impact of a second tropical cyclone in a matter of weeks.

Ex-tropical Cyclone Luana made landfall as a Category 2 system when it made landfall along the Dampier Peninsula north of Broome.

Wind gusts up to 106km/h were recorded north of Broome, in Lombadina, along with more than 100 millimetres of rain since midnight on Saturday.

The storm has since weakened to a tropical low, but could still bring falls of up to 200mm in parts of WA.

Residents along the Kimberley coast should expect heavy rainfall and damaging winds over the long weekend, which is only expected to ease from Tuesday.

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