The mercury will hit 38 degrees in Adelaide today and climb above 40 degrees in other parts of South Australia as a hot air mass envelops south-eastern states.
The extreme conditions in SA triggered a severe heatwave warning by the Bureau of Meteorology, expected to last for the rest of the week.
Other parts of Australia will feel the burst of sultry weather when it spreads to New South Wales and Queensland by the weekend, reports Weatherzone.
READ MORE: Heat records under threat during wet and humid summer
This week Adelaide residents can expect little relief at night time from the heat and humidity, with minimum temperatures lingering in the mid-twenties through the evening.
Other parts of SA today are heading for maximum temperatures above 40 degrees. The mercury will hit 41 degrees in Port Augusta, while Oak Valley in the state's north-west will sweat through a 44-degree day.
The heat will ease tomorrow, but cricket fans can expect a maximum of 33 degrees when the Test match between Australia and India begins at the Adelaide Oval at 2.30pm.
In Victoria, the heat will peak tomorrow, with Melbourne heading for a top temperature of 34 degrees before conditions ease later in the day.
The extremely humid conditions will make the temperature feel two to four degrees hotter than the actual temperature when they reach NSW and Queensland.
https://twitter.com/BOM_SA/status/1864412246471745615?ref_src=twsrc%5EtfwThe mercury will soar to 33 degrees in Sydney on Saturday, while Brisbane is forecast for a top of 34 degrees on Sunday.
From early next week, conditions are forecast to cool ahead of another warm spell rolls in.
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