Heatwave, fire, flood and cyclone: Sydney temperatures peak at 43C ...

Temperatures in New South Wales soared above 43C on Saturday and bushfires burned across the state, as Cyclone Jasper loomed off the coast of Queensland.

The temperature at Sydney airport and Badgerys Creek reached 43C at 1pm, while the mercury at Sydney Olympic Park peaked at 42.5C at 3pm and Penrith was sitting on 42.9C at 4pm.

Relief was expected in the form of a cool southerly change to arrive between 6pm and 8pm on Saturday, with temperature drops of at least 10C.

A severe thunderstorm warning was issued for parts of the south coast and Snowy Mountains on Saturday afternoon, with damaging wind gusts likely and large hailstones possible.

There were 85 grass and bushfires – 21 of them uncontained – burning across the state, with total fire bans in place in many areas, the state’s Rural Fire Service said.

The heatwave prompted warnings to the roughy 100,000 music fans heading to Sydney Olympic Park to watch the Foo Fighters and 50 Cent and to attend the Epik indoor music festival.

HSU Events, the organisers of Epik, were urging festival-goers to hydrate and take precautions, with temperatures at the festival site exceeding 40C.

Dr Darren Roberts of NSW Health echoed those concerns, saying: “Overheating during activities in dangerous heat is a huge risk, and people need to take a break from dancing, seek shade, drink water and cool down to reduce the risk of overheating at festivals.”

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Saturday was expected to be the hottest day of the NSW heatwave, which was notable for its spread across the state.

Miriam Bradbury of the Bureau of Meteorology said the intense conditions were coming across the Great Dividing Range – and even a sea breeze would not spare coastal areas.

“This is not just the Sydney area,” she said. “All the way up to the Newcastle coast, temperatures are pushing 40C.

“Sydney is going to see a bit of relief going into Sunday with the cool change, but it’s going struggle to penetrate inland,” she said.

While residents across NSW battled the heat, parts of South Australia experienced intense rain and flooding.

Meanwhile, severe tropical cyclone Jasper was looming off the Queensland coast, tipped to make landfall in the middle of next week, bringing destructive winds and heavy rain.

As of Saturday afternoon, the category 4 system was in the Coral Sea about 1,000km east of Cairns and had started to swing towards northern Queensland.

Earlier in the day, a rescue helicopter safely evacuated four Bureau of Meteorology scientists from a remote weather station on Willis Island in the path of the wild weather, about 450km off Cairns.

The cyclone was expected to make landfall between Cooktown and Townsville by mid-next week but was set to weaken at the weekend, dropping to a category 2 by Monday.

In South Australia, Adelaide was expecting close to 50mm of rain over the weekend, with more than 100mm to parts of Eyre Peninsula.

The extreme weather comes a day after scientists from the EU climate change service Copernicus confirmed 2023 would be the hottest year on record.

Dr Simon Bradshaw, a research director at the Climate Council, said climate change was threatening “the health of people andplaces we love”.

“This ferocious heat, and the confirmation that this year is the hottest on record, is consistent with what science has warned us to expect,” Bradshaw said. “That same science tells us that if we do not act swiftly, things will only get much worse.

“If we continue to recklessly burn more coal, oil and gas, heatwaves will become so extreme that some parts of the country will become effectively uninhabitable. We can’t keep stoking the fire if we want the room to cool down.”

AAP contributed to this report.

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