Euan Ferguson said that it was well known that a fire could travel rapidly up the northern face of Mount Dandenong, the highest peak of a region home to thousands of people. The potential for a fire's rapid advance up the mountain had been borne out in previous fire experience and by fire simulation tools, he said.

"Both experience and the science will tell us that there is very little margin for error. It will happen very very quickly. And I think importantly, there may not be much warning."

"A lot of people just wouldn't realise, that from the start of a fire at the base of Mount Dandenong under severe or extreme or code red conditions, it can get up to the top in less than 10 minutes. Even if they were to leave early as soon as a fire started, the road infrastructure isn't built to see a massive exodus of vehicles in that very short time frame," Mr Ferguson said in an interview at the launch of Victoria's bushfire aircraft fleet.

"So what our message is – on those days particularly where the fire danger rating is severe or extreme or code red, choose to leave early, choose to leave very early on the morning of that bad day, or choose to leave in the evening of the day before. Go somewhere where it's a position of relative safety, stay with some friends, go shopping in Melbourne. And then come back after the weather conditions have moderated."

Mr Ferguson said most of Victoria had experienced an "underlying moisture deficit" for the last three years. And most of Victoria had a very dry end to winter and a very dry spring.

The fire season would start a little bit later in East Gippslandbecause of recent rainfall, he said.

"All Victorians and visitors to bushfire prone areas need to be cognisant of the potential risk for fires. The risk is very real. It may be a little bit slow in Gippsland, but we've already seen a number of troublingly large fires in the northern part of the state in the last couple of weeks."

Mr Ferguson identified three heavily treed and heavily populated parts of the state that were a particular fire concern, describing them as areas "that would keep the fire chiefs awake at night". These were the eastern part of the Otways, the Wombat Ranges/Mt Macedon, and the Dandenong Ranges.

"The last time there was a major fire through the eastern part of the Otways was on Ash Wednesday in 1983. So that's well overdue for a significant fire. Of course it's an area of large population influx over the Christmas/New Year holiday period," he said.

The Dandenongs have not had a significant fire since 1997, a fire which claimed the lives of three residents,  including a young married couple.

Emergency Services Minister Jane Garrett warned that this fire season could be "even worse" than last season, when fire services tackled 4600 fires. "This is going to be a very challenging fire season."

To help combat the risk of fire the Department of Environment and Primary Industries has carried out more fuel reduction burning so far this financial year, in excess of 33,300 hectares, than in any other spring burning period except for one. Burns were carried out on Monday to protect homes at Warneet on Westernport Bay and at Frankston North, to remove a build-up of fuels such as tea tree, bracken, dried grasses, fallen branches and other flammable material.

Chief fire officer of the Department of Environment and Primary Industries, Alan Goodwin, said he was pleased with the work done in spring.

"Planned burning is really important to reducing fuels and helping reduce the risk of large bushfires," he said.