Melbourne's hottest day in five years has brought bushfires and managed rolling power blackouts affecting about 60,000 properties.
Victoria has sweltered through a day of intense heat, with Melbourne experiencing its hottest day in five years.
The Bureau of Meteorology reported the temperature in Geelong reached 44C, while Melbourne peaked at 42.3C, with the temperature dropping back about 2pm.
The Australian Energy Market Operator, which manages the power network, directed load shedding - rolling blackouts in isolated parts of the network to avoid damage to the entire network during high demand - across the grid.
Chief executive Audrey Zibelman said the outages would affect about 60,000 customers for up to two hours.
"Hopefully what we'll do is we'll see it through, it will be for a temporary period of time, they'll restore it," she said.
AEMO also activated emergency reserves, including preparing to pay some businesses to voluntarily curtail their own usage, but those reserves were not enough to cover the shortfall.
Victoria is also importing power from South Australia, Tasmania and New South Wales, but cannot import more because interconnectors are at their maximum limits.
The blackouts occurred as authorities battled an out-of-control bushfire threatening homes in east Gippsland in the state's east.
A total fire ban is in place across the entire state today, with the fire danger rated extreme for the North Central, Northern Country and Mallee districts.
Emergency Management Commissioner Andrew Crisp warned that the extreme weather meant that any fires sparked today would be "uncontrollable".
"They will be fast moving ... I believe we're well and truly ready as a sector. The question is, members of the public, are you ready?"
He said 500 emergency management staff were in place across the state, and 60 planes and helicopters were poised to tackle fires.
Emergency Warnings were in place for Timbarra Settlement, Mt McLeod, Butchers Ridge, Gelantipy, Gillingall, Murrindal and W Tree in remote east Gippsland.
A relief centre was set up at the Buchan Recreation Reserve and authorities warned any residents at nearby Gillingall to leave their homes before conditions became too dangerous.
"Emergency Services may not be able to help you if you decide to stay," the warning said.
A mass of hot air that had been building over central Australia yesterday brought record temperatures to South Australia, where Adelaide hit a sweltering 46.6C, surpassing Melbourne's Black Saturday record for the highest temperature in an Australian capital city.