PEOPLE in the Mallee, Wimmera and Central Victoria must take this week's fire danger seriously, Emergency Services Commissioner Craig Lapsley says.
With temperatures due to soar over the next week, Mr Lapsley has warned that a lack of significant rain in those districts made them most at risk.
And with consecutive days of heat to come, he said all parts of the state could become at risk, with a pick up in winds next week and later in the month to heighten the threat.
Emergency Services Minister Jane Garrett revealed on Thursday that since December the CFA had responded to more than 170 suspicious fires.
"That is nearly three-a-day deliberately lit fires which are threatening to all of us," Ms Garrett said.
"These figures are terrifying."
Deliberately lit fires include both arson and people being negligent and reckless on hot days with tools, camp fires and cigarette butts.
Authorities have called on people to be vigilant and report suspicious behaviour by calling Crime Stoppers.
Victoria Police acting deputy commissioner Shane Patton said eight people had already been charged with arson this fire season.
Arson causing death carries a prison term of up to 25 years, while people who recklessly cause a fire can face jail of up to year and a $17,000 fine.
"It's not just deliberate arsonists we are targeting, we need to get that prevention message out as well to people to say you need think about using common sense," he said.
Mr Lapsley said hot weather in central Australia was an early warning of conditions that would hit Victoria.
He said central and western Victoria were the driest parts of the state, but warned that a few days of hot weather would create fire conditions across the state.
"Anywhere in Victoria can change with the type of heat we are about to get," Mr Lapsley said.
Victorian firefighters working in WA will return on Sunday and Monday.
