Temperatures in some parts of the state had exceeded 40 degrees Celsius by midday with strong winds also recorded.
A Parks Victoria spokeswoman said hundreds of campers had been evacuated from parks across the Wimmera, including the Grampians National Park, which is the largest in the district, as the area faces a code red catastrophic day.
Others parks experiencing evacuations include Little Desert National Park, the Black Range State Park and the St Arnaud Range National Park, where there was a bushfire false alarm earlier in the day.
Warning to residents
In Melbourne, temperatures will peak after 5pm, authorities said.
Police said earlier on Monday the heat was more dangerous than the fires and urged people to leave work early or wait until after 7pm to ease the strain on the public transport system.
Authorities have warned that the heatwave won’t end today with up to three fire districts facing catastrophic conditions tomorrow.
Country Fire Authority (CFA) state controller Russell Rees warned Tuesday will also be a dangerous day for fires and urged residents to leave early.
“We want people to prepare and understand that we are in a very difficult weather scenario with a wind change coming, the potential for a very hot night and very real risk for Victorians, for the western and central part of the state today leading into the evening and the north eastern part of the state tomorrow,” he told reporters in Melbourne.
Mr Rees said a code red did not mean everyone in the area should leave, but those in high-risk areas should move to bigger towns.
He said the CFA’s website temporarily experienced technical difficulties on Monday morning, but the problems were quickly fixed.
Police Commissioner Simon Overland urged people to keep themselves and their families safe.
“What we say to the community is if you are in those areas and you are in a high-risk environment your safest option is to leave,” he said. “The worst decision you can make is to stay and go late.”
“The extreme weather event itself … poses probably a greater risk than the fires at this point,” he said. “The weather …will peak later in the day … the hottest part of the day will be somewhere around 5pm on.”
Authorities have one less worry after a bushfire emergency near St Arnaud in western Victoria proved to be a false alarm.
Seventeen firefighters rushed to the St Arnaud Range National Park about 11am after a fire spotter reported seeing smoke from a nearby tower.
But when crews arrived there was no fire, a Department of Sustainability and Environment (DSE) spokeswoman said.
In South Australia, catastrophic warnings are in place for the Eastern Eyre Peninsula, Lower Eyre Peninsula, West Coast, Mid North, Yorke Peninsula, Murraylands, Upper South East, Lower South East, Kangaroo Island and the Mount Lofty Ranges.
The South Australian Country Fire Service says people in those areas still have time to leave their homes for a safer place.
A fire burning near the Edinburgh RAAF base in Adelaide’s north has been brought under control.
The Country Fire Service said 45 firefighters attacked the blaze this morning and had it contained in 40 minutes.
Two water bombing aircraft were also deployed, making one drop each.
The fire destroyed about three hectares of grassland and came as South Australia sweltered through its fourth consecutive day of 40-plus temperatures, therefore facing catastrophic fire dangers.
The temperature in most districts is forecast to reach the low 40s Celsius, with a cool change expected overnight.
Fire bans are also in place in Tasmania and parts of southern New South Wales.