Multiple emergency warnings have remained in place overnight and into this morning across parts of Victoria as firefighters battled blazes across the state.
People in Avenel, Longwood, Longwood East, Ruffy, Tarcombe and Upton Hill were advised to "take shelter now", with authorities saying it's too late to leave as they work to bring the Longwood bushfire under control.
Those in Caveat, Dropmore, Ruffy, Tarcombe and Terip Terip were advised to "leave immediately" as the Longwood fire headed in a south-easterly direction towards Ruffy.
LIVE UPDATES: Get the latest fire and emergency warnings here
The fires come amid heatwave conditions across the south-east of Australia, with temperatures being compared to the summer of 2019-2020, which is known as Black Summer.
Melbourne recorded its hottest day in six years on Wednesday as the mercury spiked at 41C.
The state's capital wasn't alone, with four other spots recording their hottest days since 2019: Longerenong (44.3C), Edenhope (42.6C), Hamilton (41.8C), and Casterton (41.6C).
READ MORE: Firefighters battle tough conditions as parts of South Australia reach 45 degrees
The three-day heatwave, which kicked off on Wednesday, is expected to only intensify further towards the end of the week.
Temperatures are forecast to reach 45C in Mildura, in the state's north-west, on Friday, with the region forecasted to see its first three-day spell above 44 degrees since 2018.
In the north-east, near Albury-Wodonga, temperatures are forecasted to reach 43C and Melbourne could see hotter conditions than its 41 on Wednesday.
Weatherzone warns that the extreme heat will couple with strengthening north-north-westerly winds ahead of a cold front, which will spark the worst of the fire danger across Victoria.
They predict "catastrophic fire danger" on Friday for the Wimmera, Northern Country and North Central districts, while the rest of Victoria remains at the "extreme fire danger" category for the end of the week.
Forest Fire Management Victoria Chief Fire Officer Chris Hardman feared Friday's conditions could see "lots of assets lost".
"With the conditions we have ahead of us, these fires will not be able to be suppressed," he said.
Total fire bans are in place across large parts of the state but forecasters predict thunderstorms and dry lightning could spark blazes and winds could propel the fires.
"If we can't catch those fires when they're small, and I mean really small, one tree burning, through lightning, those fires are going to get big and have dreadful impacts on the community," Hardman added.
The Bureau of Meteorology has heatwave and fire weather warnings in place.
You can read the BoM's latest advice and warnings here.
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