The current record of 50.7 degrees was set in January 1960 in the outback town of Oodnadatta in South Australia.
Temperatures have been high over the weekend in Western Australia.
Forecasters say the extreme heat is expected to affect the rest of the country in the coming week, with temperatures likely to exceed 40 degrees in many areas from Wednesday.
Australian firefighters are struggling with out of control bush fires as hot and dry weather continues.
Total fire bans are in place for parts of New South Wales with 100 bush fires currently burning.