Residents are bracing for hot conditions with the temperature in Melbourne forecast to reach 36 degrees on Thursday and an extreme 43 on Friday.

The temperature will not drop below 29 overnight on Thursday and air conditioners across Victoria are expected to get a fierce workout.

Australian Energy Market Operator chief executive Audrey Zibelman told Fairfax AEMO certain large businesses may be offered an electricity discount to power down under its Reliability Emergency Reserve Trader (RERT) policy.

A decision on whether to enact the RERT system to take pressure off the electricity grid will be made on Thursday.

View photos A woman is seen skateboarding during a hot day at St Kilda beach in Melbourne. It’s expected to hit 36C in the city on Thursday. Source: AAP More

“These reserves give us the ability to deal with these heatwaves, that’s why we have the RERT in our back pocket,” Ms Zibelman told Fairfax.

She’s also asked residents “to be conscious to not use more energy than they need”.

View photos There are concerns there might not be enough power to supply all of Victoria due to rising temperatures on Thursday. Source: AAP (file pic) More

Concerns over drowning risks

“The overnight minimum temperatures are nothing short of oppressive unfortunately,” the Bureau of Meteorology’s Richard Russell said of the conditions expected for Victoria.

Authorities are asking people not to take risks during the hot weather, including leaving children in cars or swimming at unpatrolled beaches. Twenty people have drowned in Victoria since December 1.

“Let’s take something from these drowning deaths. Twenty people have lost their lives, that’s 20 families and friends of those people that have been impacted,” Emergency Management Commissioner Andrew Crisp said.

A cool change is expected late on Friday, but it will bring wind gusts of up to 80km/h, thunderstorms and an increased fire risk.

Fire crews are on stand-by while extra paramedics and ambulances will be on call to assist those struggling in the heat, Mr Crisp added.

View photos A man is seen sunbathing on the foreshore during a hot day at St Kilda beach in Melbourne. Source: AAP More

Adelaide temperature set to threaten 80-year record

South Australians are being warned of dangerous bushfire conditions as the state prepares for a day of record-breaking heat.

Adelaide is forecast to hit 45C on Thursday, but the Bureau of Meteorology says the city’s 80-year-old record high of 46.1C is within reach.

“You wouldn’t rule it out,” forecaster Jonathan Fischer said.

View photos Beachgoers sunbath at Glenelg beach during a hot day in Adelaide. Source: AAP More

The heat will intensify in the state’s regional centres, with a high of 49 expected at Port Augusta, and 47 at Port Pirie and Roxby Downs.

“Nowhere is going to escape,” Mr Fischer said.

“We will see records broken tomorrow, with many locations forecast to be near their maximum all-time record.”

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