While Prime Minister Scott Morrison is overseas on vacation, Australia this week experienced its hottest day on record and the heat-wave is expected to worsen, exacerbating an already unprecedented bushfire season, authorities said on Wednesday.
The average nationwide temperatures of 40.9 degrees Celsius on Tuesday beat the previous record of 40.3 degrees Celsius in January 2013, the Bureau of Meteorology said.
This heat will only intensify further today, meteorologist Diana Eadie Said.
The heat wave is another alarm bell about global warming in Australia, where this year's early and intense start to regular summer bushfires has heaped pressure on the Australian government to do more to tackle climate change.
Hundreds of bushfires have been raging across Australia for months, including a mega-blaze burning north of Sydney, the country's biggest city.
Smoke from the fires has engulfed Sydney, raising air pollution to levels so hazardous that leading doctors have labeled the event a public health emergency.
At least three million hectares of land has been torched across Australia, with six people killed and about 700 homes destroyed.
Scientists say the blazes have come earlier and with more intensity than usual due to global warming and a prolonged drought that has left the land tinder dry and many towns running out of water.
The fires have sparked climate protests targeting the conservative government, which has resisted pressure to address the root causes of global warming in order to protect the country's lucrative coal export industry.
Record spot temperatures were recorded this week in Western Australia, where firefighters have also been battling blazes raging across thousands of hectares (acres) of land.
The hot weather then began drifting across the country's arid centre toward the heavily populated eastern states, where the most of the bushfires have raged.
Parts of the eastern state of New South Wales, of which Sydney is the capital, were forecast to reach the mid-40 degrees Celsius on Thursday.
On Saturday parts of Sydney are forecasted to tip over 46 degrees Celsius.
Turbulent winds of up to 100km an hour are forecast to also hit the east coast at the same time and worsen the blazes.
Over the next few days we are going to see firefighters, the emergency services and all those communities close to fires ... challenged with a new threat, New South Wales fire commissioner Shane Fitzsimmons said Wednesday.
Embers carried by the winds can travel up to 30km from a blaze, authorities said.