TEMPERATURES across eastern Australia had pushed above 40 degrees well before noon on Friday, although a cool change currently pushing through South Australia is likely to see a rapid drop in temperatures.
Renmark hit 44 degrees around 11.30 SA time, while Mildura was at 43, while into western NSW, the mercury at centres such as Tibooburra and Bourke was also nudging 40 before midday.
But the change is on its way.
At Adelaide Airport the temperature fell four degrees in just half an hour from 4 to 4.30 in the morning, while Lameroo dropped from over 40 to 35 in a similar timeframe.
While the change will bring relief in terms of the heat it is expected to bring its own challenges.
Blustery south-westerly breezes and dry lightning may be a feature of the change, meaning the fire risk remains extremely high in many districts.
It is a total fire ban across all of Victoria today, with extreme fire danger, the second highest rating behind catastrophic, for the Wimmera and Mallee.
In SA, there is a severe fire danger rating for the Flinders, Mid North and Riverland fire districts.
At present the national fire focus is on Tasmania, where a number of blazes are burning out of control.
The hottest temperatures are expected in eastern Victoria and the south-western Riverina, where the change will not blow through until this evening.
Centres such as Swan Hill, Echuca and Deniliquin are all expected 46 degrees, while in Finley, in the Riverina, the Bureau of Meteorology (BOM) expects the mercury to nudge 47 degrees.