Vic firefight changes as state heats up

A return of summer heat this week is forcing firefighters to change tactics as they battle an out-of-control blaze in Victoria's Otway Ranges.

The devastating Wye River Jamieson's Track fire razed 116 houses in the Great Ocean Road towns of Wye River and Separation Creek on Christmas Day.

It has now burned more than 2500 hectares and is deep in forest country and posing no threat to lives or property.

Some of the 300-strong firefighting force will be pulled out on Monday as temperatures up to the mid-30s return after a mild week that's dampened fire activity and helped crews build containment lines around the blaze.

"It's incredibly dangerous, inaccessible terrain in this area," incident controller Alistair Drayton told AAP.

"We've got some of the biggest trees in Australia, 300-year-old ash, tall timber and 30-degree slopes, so it's very challenging."

Crews have used the favourable weather to get close to the fire, Mr Drayton said.

"But now we're going into a warming cycle, we'll be pulling our crews out from there and changing our strategy from one of extinguishing to one of containment," he said.

"We'll minimise the direct attack tomorrow and use a lot more aircraft, do it from a distance."

At least eight fire-bombing aircraft will attack the fire from Monday, with more planes including large air tankers on call and minutes away, while firefighter numbers will be boosted on the flanks.

Mr Drayton urged residents and visitors to remain aware of the conditions, listen to emergency broadcasts and check the FireReady app.

"It's important and it's safe to support all the coastal communities at the moment," he said.

"That's not to say the situation may not change, but at the moment the fire is in the middle of the Otways and we're attempting to keep it there."