Drivers have been warned to expect delays after a 10-kilometre stretch of a Victorian freeway melted.
Victoria Police asked motorists to avoid the right-hand lane of the Hume Freeway near Broadford, north of Melbourne.
"There is a 10km stretch of road that is melting," Victoria Police tweeted.
According to VicTraffic, southbound lanes of the Hume Freeway between Breens Road, Tallarook to Marchbanks Road, Broadford are closed due to 'road damage' as at 6.30pm on Friday.
Passenger Steph Harris tweeted photographs of the road, saying: "Traffic at a stand still on the Hume outside Broadfoard due to melting tar."
A sealing contractor was at the scene patching up the road, nine.com.au reported.
Broadford reached 30C at 6pm on Friday with the mercury set to surge to 40C on Saturday, according to Weatherzone.
Heat health alerts have been issued for three Victorian districts as authorities expect a dangerous heatwave.
Melbourne is forecast to reach 41C on Saturday, with northerly winds reaching up to 40km/h.
Geelong and Bendigo are forecast to reach a high of 42C on Saturday, and Avalon, Echuca and Warracknabeal 43C.
"This heat is a killer. It's going to be like a blast furnace tomorrow and you need to adjust what you do," Ambulance Victoria's state health commander Paul Holman told reporters on Friday.
There are bushfire warnings for New South Wales, South Australia and Tasmania at the weekend.
- with AAP
