Firefighters are working to bring freshly sparked bushfires under control amid heatwave conditions, with nearby residents advised to monitor the situation.
With total fire bans in place in Victoria amid an extreme fire danger, firefighters responded to fresh blazes on Sunday afternoon in the state's Central Goldfields region.
Residents were advised to stay informed as crews worked to control fires at Moliagul, west of Bendigo, and near Maryborough, north of Ballarat.
The extreme fire conditions in the nation's southeast came as residents sweltered through the third day of a major heatwave.
The hot and dry weather stretched from central Australia to the southeast, with pockets in Victoria's east and NSW's southeast experiencing severe heat.
Conditions were set to become more "unsettled" as winds began to shift and clouds moved in, Victoria State Control Centre spokeswoman Reegan Key said.
"People will notice the cloud cover today a bit more, and that creates more tricky conditions for firefighters," she told AAP on Sunday.
"Where we already have fires in the landscape, sometimes the winds can be a bit difficult, but equally there is potential for lightning across the state so we might see some new starts."
Total fire bans were in place for the districts of Mallee, Wimmera, South West, North Central and Central, including Melbourne and Geelong, which meant no fires could be lit in the open air.
A cool change with below-average temperatures and patchy rain is forecast on Monday.
A fire in the Grampians National Park that began in mid-December continues to burn out of control but at a slower rate.
More than 76,000 hectares of the park - equivalent to the size of Singapore - have burnt and four houses and several other buildings have been destroyed.
Crews have been working to contain the fire and enable residents and tourists to return to Halls Gap and surrounding areas.
"If we can get through today, they are likely to declare that fire contained in the next couple of days," Ms Key said.
The Bureau of Meteorology issued a heatwave warning for SA, NSW, Victoria and Tasmania, with temperatures set to reach the 40s in some parts of the country on Sunday.
Meteorologist Miriam Bradbury said the mercury was set to push into the high 30s to low 40s across Victoria with above-average temperatures for South Australia and Tasmania before heatwave conditions moved into NSW.
In NSW, fire crews were battling 46 fires across the state on Sunday amid concerns possible thunderstorms could make matters worse.
Some of those fires were burning in or around the Yengo and Wollemi National Parks and near the Attunga State Forest.
Campers must ensure they put out campfires before leaving the site after firefighters responded to 50 unattended fires in 2025, Forest Fire Management Victoria Commander Dave Sayce said.
