This frame grab from video footage taken and provided by Australian Broadcast Corporation (ABC) on December 21, 2023 via AFPTV shows firefighters in the suburb of Parkerville, east of Perth, attempting to put out a bushfire. (PHOTO / ABC / AFP)

SYDNEY - Large parts of Australia on Sunday sweated through heatwave conditions as authorities warned of a high bushfire risk in many parts of the country's vast Western Australia state.

The nation's weather forecaster on Sunday issued heatwave alerts for the western state, the neighboring Northern Territory and the eastern Queensland state, warning temperatures in some regions could hit around 45 degrees Celsius (113 degrees Fahrenheit).

In Perth, the capital of Western Australia, the nation's largest state, a maximum temperature of 35 C (95 F) was forecast for Sunday, more than five degrees above the December mean, forecaster data showed

In Perth, the capital of Western Australia, the nation's largest state, a maximum temperature of 35 C (95 F) was forecast for Sunday, more than five degrees above the December mean, forecaster data showed.

Australia's east was this month scorched due to El Nino, a climate pattern in which unusually warm Pacific Ocean temperatures cause heatwaves, cyclones, droughts and wildfires.

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In Western Australia, more than 20 bushfires were burning on Sunday, the state's emergency services agency said on its website, including an uncontrolled one near Pemberton, a town of around 5,000 residents, about 320 km (198 miles) south of the state capital Perth.

A Department of Fire and Emergency Services spokesperson said in a statement the agency was expecting "more difficult fire weather" from Sunday afternoon as hot, dry and windy conditions hit a large section of the state, including Perth.

The agency warned of a high fire danger for many areas of Western Australia and said more than 1,000 firefighters had been fighting blazes statewide over the past five days.

"Weather conditions over the next few days will put pressure on containment lines and potentially increase fire activity," the spokesperson said.

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Much of Australia's east coast was in line for torrential rain, with the weather forecaster issuing flood alerts and a severe thunderstorm warning late on Sunday for parts of New South Wales, the country's most populous state with Sydney as its capital.