The relentless heatwave continues to grip southeastern Australia, prompting authorities to remain vigilant as fire risks escalate with unpredictable conditions.

Forecasts from the Bureau of Meteorology indicate that temperatures will rise sharply in parts of Victoria and South Australia on Tuesday, potentially setting new records for extreme heat.

Melbourne is bracing for its hottest day since the catastrophic Black Saturday bushfires of 2009, with temperatures expected to peak at a scorching 45 degrees Celsius.

In Victoria’s far north, Mildura is predicted to reach an unprecedented 49 degrees Celsius, while Broken Hill in New South Wales may see temperatures climb to 47 degrees Celsius, both poised to break historical records.

“Should Mildura hit that mark, it will set a new record for the highest temperature ever recorded in Victoria,” explained senior meteorologist Dean Narramore.

“Pretty much all observation points near the SA and Victorian border are either approaching or likely to exceed January records and a few locations could also break their all-time records.”

Total fire bans in place

It comes as a total fire ban remains in place for both Victoria and SA as several fires burn out of control under dynamic conditions.

Records were broken on Monday in Adelaide where the temperature reached 44.7C, exceeding the city’s previous Australia Day heat record set in 2006.

Ceduna, north-west of the capital, climbed to 49C, surpassing its previous record temperature, while NSW town Dubbo reached 46.1C to record its hottest January day.

The weather conditions are worrying authorities in Victoria as multiple fires continue to burn out of control, including in the Otways where a blaze jumped containment lines at Carlisle River on Saturday, threatening the small community of Gellibrand.

Authorities say there has been unconfirmed property loss within the fire grounds.

The bureau warns gusty south-westerly winds will hit Melbourne on Tuesday afternoon, with a risk of thunderstorms producing dry lightning.

Fires could spread ‘quickly and unpredictably’

A cooler change will begin to move through Victoria on Wednesday, although inland parts of the south-east won’t see much of a reprieve.

Deputy incident controller Alistair Drayton says the gusty change is worrying, with authorities urging residents living in Gellibrand, Kawarren, Beech Forest, Forrest and Barongarook to evacuate.

“The conditions tomorrow mean the fire could spread quickly and unpredictably. We strongly recommend people in affected areas to enact their bushfire plan, and leave early to protect themselves and their families,” he said.

The heatwave conditions have also sparked a warning from paramedics, who responded to 11 cases of children locked in cars over the weekend as temperatures soared into the 40s in Victoria.

Ambulance Victoria urged the community never to leave children, pets, or older people unattended in vehicles.

“The temperature inside a vehicle can double and become deadly within minutes,” director of emergency management Dale Armstrong said.

“It is particularly dangerous for children to be left inside vehicles, as a child’s body temperature rises three to five times faster than an adult.”

Residents in both states are urged to drink plenty of water, check on family, friends, and neighbours to see if they need help and stay indoors.

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