Multiple states are sweating through heatwave conditions with the mercury predicted to soar close to 50C in parts of Western Australia.
Warnings have been issued to residents in NSW, South Australia and WA on Sunday to prepare ahead of uncomfortably high temperatures.
The Pilbara, in northern WA, a high of 48C is forecast in Mount Augustus and Paraburdoo and is expected to remain at about 40Cs until midweek.
Sydney is due to experience its hottest day of the year so far, with the CBD climbing to 37C while people in Penrith will feel the heat nudge up to 40C.
Far-west and northern NSW will see the worst of the heat though, with Tibooburra due to get up to 43C.
The severe heat will stretch into northern NSW, with the north west slopes and plains staying hot into mid-next week.
Maximum temperatures in the high thirties to low forties are forecast for towns in the north including Moree.
Temperatures are expected to climb to the mid to high thirties on Sunday in southeast Queensland as a severe heatwave warning is issued for the region.
This will increase to the high thirties to low forties inland by the start of next week.
Locations likely to be impacted include Bowen, Birdsville, Brisbane Metropolitan Area, Beaudesert, Boonah, Gladstone, Ipswich, Woorabinda and Yeppoon.
For those enduring heatwave conditions on Sunday, the bureau has urged them to stay inside where possible.
“Severe heatwaves can be dangerous for many people, especially older people, babies, children, pregnant and breastfeeding women, people with medical conditions and people who are unwell,” the bureau said.
Experts suggest seeking a place to keep cool, such as home, a library, community centre or shopping centre.
Close windows and draw blinds, curtains or awnings early in the day to keep the heat out of the home.
If available, use fans or air conditioners to keep cool.