Power brown-outs have not been ruled out as Melbourne gets ready to sweat through its hottest day in 10 years and a number of spots across the state brace for possible heat records.
Energy Minister Lily D'Ambrosio says three power generators across Yallourn and Loy Yang A have shut down, as infrastructure struggles to keep up.
"This means we can't rule out brown-outs," she told 3AW on Friday.
She urged Victorians to ration their non-essential electricity use.
As many wake bleary eyed after a hot, sleepless night, it appears no 24-hour records were broken across the state, according the weather bureau.
However, some spots in northern Victoria are on track to break records, with Mildura and Kerang, whose hottest days reached 46.9 degrees, are both forecast for 47.
"Certainly a number of locations will be nudging records today," Bureau of Meteorology senior forecaster Michael Efron told AAP.
A large part of central and northern Victoria and even Gippsland are expected to reach the mid 40s ahead of a gusty, south westerly change.
The change will reach the southwest of the state later on Friday morning, then move to central areas in the afternoon.
Melbourne is set for a top of 44, which if reached will be the hottest day in 10 years, since Black Saturday, February 7, 2009.
By 7.40am on Friday, Melbourne was already 35 degrees.
"Melbourne is one of the hotter places at the state at the moment," Mr Efron said.
"I think we will hit the 40 degree mark late morning or midday in the Melbourne area with that temperature peaking just before the change arrives.
"Between about 2.30 or 3pm, we'll see that maximum of 44 but then a significant decrease in temperature into the late afternoon, with that squally south westerly change."
The change is forecast mainly for the central and eastern districts and brings risk of rain and thunderstorms.
There is also a risk of dry lightning, which could spark more fires.
The change is expected to reach other parts of the state later in the evening but the northeast of the state, in places such as Albury, won't see relief until Saturday, when it is forecast to hit 41 degrees.
Authorities are urging people not to take risks during the hot weather, including leaving children in cars or swimming at unpatrolled beaches.
