Victorian firefighters are battling blazes during the most serious fire day in the state in five years, Fire Services Commissioner Craig Lapsley says.
Dynamic conditions and hot, windy and dry weather were hampering the efforts of fire crews, Mr Lapsley said.
"(Fires) have been intense, fast-moving and in some cases have been that fast-moving (they) have moved onto properties with limited time to warn those residents in that area."
Mr Lapsley said a wind change on Sunday afternoon would worsen conditions for firefighters.
"The impact on properties, potential to have impact on life is still real and happening this afternoon," he said.
He said cooler temperatures on Monday would assist firefighters, but the danger was still there.
"Tomorrow will be cooler. However, it doesn't change the conditions, it doesn't bring rain and we will see the fire danger decrease but the fire will still have the potential to do damage over the next number of days," he said.
Premier Denis Napthine said extreme weather conditions had created serious fire situations across the state.
But he said the emergency response had been outstanding and had taken on board the lessons learned from Black Saturday.
"We now have better warning systems," Dr Napthine said, speaking at the State Control Centre.
"We now have a better system of all emergency services agencies working together.
"We now have a community that's more alert, more ready to respond to warnings.
"While we have a number of fires and there are still communities facing the challenges of those fires, we have seen a better co-ordinated response and a better result than in the past five years."
The Black Saturday fires killed 173 people and destroyed more than 2000 homes and thousands of other buildings on February 7, 2009.
Dr Napthine said there are 70 going fires and 143 warnings have been issued to communities on Sunday.
