Total fire bans have been declared in the Mallee, Wimmera, South West, North Central and Central (including Melbourne and Geelong) districts.

“Heatwaves can be incredibly dangerous, and they kill more Australians than any other natural event.”

A heatwave warning for South Australia, NSW, Victoria and Tasmania has been issued by the Bureau of Meteorology, with temperatures set to reach the 40s in some parts of the country on Sunday.

“Low-intensity heatwaves are common at this time of year, but once we get into the severe category, especially with a run of hot days and warm nights, some people can find it challenging,” he said.

A number of those fires are burning in or around the Yengo and Wollemi National Parks and near the Attunga State Forest.