Businesses hit hard as fire panic fuels cancellations

A wave of cancellations is hitting hospitality businesses at great distances from the epicentre of an out of control bushfire as owners call for calm.

The blaze in the western Victoria's Grampians National Park is expected to burn for weeks, but more than 40 kilometres away in Great Western, Bruce Ahchow has seen most of his motel reservations evaporate in a matter of days, along with all of his tours and events bookings.

"(In Great Western) we are far enough away and in a very, very safe zone in relation to the Grampian's National Park," Mr Ahchow told AAP.

Four in five of his rooms are empty, at a time of year he would usually be fully booked.

While alerts were crucial to protecting the community, he said sensationalised media reporting failed to report safe spots to travel.

"That is driving people away from a very, very large part of Victoria and all of the businesses that rely on those people are suffering and will suffer for a long time," Mr Ahchow said.

Closer to the epicentre in Halls Gap, evacuated residents were given a two-hour window before lunchtime to return and collect their belongings before Christmas.

Country Fire Authority chief officer Jason Heffernan hoped the access would give some festive normality to the community.

"(This is) to ensure if the residents of Halls Gap will be relocated for Christmas, at least they will have what they need," Mr Heffernan said.

Cooler, milder conditions on Monday night helped firefighters on the ground get "some containment" of the southern Grampians fire, he said.

Grampians Tourism chief executive Mark Sleeman said the fire was costing the economy $1.9 million per day.

"We're going to need some immediate intervention and financial support from both federal and state government to reignite our local visitor economy," he told AAP.

On Christmas Day, Mr Sleeman's family will go to a safe place while he prepares to protect their home on Boxing Day, which the State Control Centre expects to bring the worst conditions since Black Summer five years ago.

"Any fire that starts on Thursday will be difficult for fire crews to control and has the potential to impact communities very, very quickly," the State Control Centre's Luke Hegarty said.

"Thursday is not a day where you should be travelling, unless absolutely necessary."

Another bushfire at Bullengarook in Melbourne's northwest has been contained, while a blaze at the Gurdies in western Gippsland continues to burn.

Holiday travellers are being warned to keep up to date with fire conditions as several states face growing bushfire risks.

About 100 fire personnel from NSW, the ACT, Queensland and Tasmania are heading to Victoria to help battle the blazes.

Elsewhere in NSW, several small bush and grass fires continue to burn but remain under control, though a significant part of the state also faces high fire dangers on Boxing Day.

South Australian firefighters urged residents to leave in the Onkaparinga Hills in the Mount Lofty Ranges as they battled an out-of-control bushfire on Monday.

They later downgraded warnings, telling residents to monitor conditions.

Regional areas across SA are expecting hot conditions on Boxing Day, with Adelaide facing a peak of 36C after a predicted 37C on Christmas Day.

A "too late to leave" bushfire alert for residents near the wheatbelt town of Northam in Western Australia was issued on Monday night and remained in place on Tuesday.