In qld, still 10degC to 25degC but super dry in winter as limited rain and often windy so when fires do start they can still get going - much easier to control though. That said this is likely back burning.

Confirmed, backburns in Greenbank https://www.fire.qld.gov.au/Current-Incidents

So yeah as the other explanation. Australia is huge. There's plenty of snow down south and of course the people that visit the ski fields are happy about that. Hundreds of miles/kilometres north is where this photo was taken. It's a sub tropical climate so think more of wet/dry. Not the same as Darwin's wet season, but yeah "summer" can bring a lot of rain.

"Winter" however is as previously mentioned, not terribly cold. And yeah it's mainly rather dry. Vast areas dry out and so fires happen. This was a controlled burn off which helps mitigate big big fires later on.

The Aboriginals did this for thousands of years ( tens of thousands ) as they had worked things out.

Hope this explains things. Where are you if you don't mind me asking ?