Dry lightning, winds up to 40 kilometres and temperatures as high as 40 degrees Celsius will cause "one of the most dangerous" fire days for Victoria in recent years.
Six of nine Victorian districts are facing total fire bans tomorrow, February 28, due to expected high temperatures and strong winds.
Residents at Ampitheatre, Beaufort, Clunes, Elmhurst, Learmonth, Lexton and surrounds have been asked to leave ahead of the fire risk tomorrow.
Victorian Premier Jacinta Allan said dry lightning is predicted for parts of the state, and weather conditions expected to be "incredibly difficult".
"Tomorrow is likely to be one of the most dangerous fire days Victoria has experienced in recent years," she said.
She said temperatures will be as high as 40 degrees Celsius for parts of Victoria, coupled with high winds, estimated between 30 to 40 kilometres an hour.
"Particularly as we see the wind change coming through later tomorrow afternoon, added to that dry lightning that is expected to move through parts of the state," she said.
Ms Allan said Colac, Warrnambool, and Portland through to the South Australian border is currently under an extreme rating, which could move to catastrophic.
She said the decision would be made later today.
Assets are expected to arrive from NSW, to be stationed near Ballarat and the Halls Gap region.
Ms Allan said there would be 66 aircrafts assisting with the fire conditions tomorrow, and arrangements have been put in place for aged care, health, early childhood and school facilities.
Six residential houses and 10 outbuildings had been destroyed, and Ms Allan said it remained a "very active fire" and a "very difficult fire to manage".
Emergency Management Commissioner Rick Nugent said the conditions would make containing a fire north of Beaufort challenging, and had the potential to "run again".
He said the State Control Centre had modelled where the fire might travel tomorrow.
"We will be sharing that through social media and other avenues to the community so they are well aware of the communities that could be impacted," he said.
"This could result in loss of homes, closure of roads and isolating communities.
"Additionally, there will be an emergency alert going to phones in this area to advise them they are in this potential impact area.
"If you live in a bushfire risk area, we are asking you to leave and to leave early."
He said there would also be five strike teams and 25 fire trucks positioned strategically at Ballarat and Ballan.
Country Fire Authority Chief Officer Jason Heffernan said the fire currently had a 200-kilometre perimeter.
He said there would be a total fire ban for the Mallee, Wimmera, South West, North Central, Northern Country and Central districts.
The ban would be effective from midnight tonight for 24 hours.
"Fires will become very uncontrollable very quickly, and no homes will be safe from those conditions," he said.
"We do anticipate the peak of the fire dangers to be later on in the day and could continue on well into the evening."
Forest Fire Management Victoria Chief Fire Officer Chris Hardman said the Grampians National Park, Little Desert National Park and Wyperfeld National Park would be closed tomorrow.
"Using fire in public land can have devastating impacts in communities right across the fire danger areas," he said.
"It is not safe to be in forested areas during extreme fire days and catastrophic fire weather days."
People can stay up to date with incidents and warnings here or on the VicEmergency app.