Australia is braced for its hottest day on record as an extreme heatwave sweeps across the country.
Experts say southern areas of the country including Victoria and New South Wales could see record-breaking temperatures, with predictions of up to 48C in some places on Friday.
It comes as firefighters battle to contain more than 100 fires burning around NSW, including the 400,000 hectare Gospers Mountain megafire in Wollemi national park in the Blue Mountains.
In January 2013, the highest maximum temperature average for a day over Australia was set at 40.3C.
Dr Blair Trewin, from the Bureau of Meteorology, said the country is expected to be at least one or two degrees above that on Wednesday and Thursday.
He added that December records would be seen over much of inland southern Australia, with some areas potentially seeing their highest ever temperatures.
"We saw significant heat build over Western Australia over the course of last week, and that heat is now pushing east over the continent, which is going to lead to several days of exceptional heat," he said.
"Australia's warmest day on record occurred in January 2013, when the average maximum temperature across the continent was 40.3C.
"We’re closely monitoring the development and progression of this heat but based on current forecasts, we could see that record broken this week."
Several areas have already experienced record-breaking heat as a result of the extreme weather.
On Monday, the mercury hit more than 40C in Queensland. In the state's town of Nambour, the mercury reached 40.8C, beating the previous record of 40.5C in 1972.
Neighbouring area Beerburrum broke its 2001 record with 41.4C, while Oakey beat its 2013 record with 40.7C.
The areas of Archerfield and Gatton, also in Queensland, broke their 2019 records with 41.2C and 40.7C respectively.
However, in Brisbane, temperatures were around 10C lower with cooler winds also bringing in "smoke haze", creating pockets of reduced air quality.
A Queensland Government health spokesman said smoke levels in the vicinity of bushfires coupled with high temperatures and strong wind could exacerbate health conditions.
"People should always be aware of the local conditions and any localised smoke sources that may still adversely affect their health," the spokesman said.
"If there are fires or other smoke sources in your local area, take reasonable precautions to minimise any potential exposure.
"If you have a medical condition, make sure that people close to you such as family members, neighbours or friends are aware of your condition and are available to help if you require any additional assistance."
The spokesman added that any adverse reactions to dust or smoke such as shortness of breath, prolonged coughing or wheezing, should be checked out by a doctor.
Bureau meteorologist Sarah Scully added: "For many areas, severe to extreme heatwave conditions will be felt, so it's important people follow the advice of health authorities, stay up to date with the latest forecasts and warnings from the bureau."
As the country geared up for "extreme" weather, experts warned the community to look out for vulnerable residents including children, pregnant women and the elderly.
