Heatwave conditions are set to persist for large swathes of the country with a cool change not expected until later in the week.
For New South Wales (NSW), temperatures are set to reach the mid-30s to low-40s during the day and low to high 20s overnight with the mercury at its highest on Jan. 25 and Jan. 26.
Severe heatwave conditions will develop across the central and northern inland parts of the state, spreading east towards Sydney, the Hunter and Mid North Coast on Jan. 23 and Jan. 24.
Armidale, Camden, Campbelltown, Hornsby, Liverpool, Moree, Nowra, Orange, Richmond and Wollongong are all set to bear the brunt of the heat.
Some regions in the northwest slopes and plains such as Walgett are expected to reach 42C while parts of upper western NSW including Wilcannia could peak at 46C.
NSW State Emergency Operations Controller, Deputy Commissioner for Emergency Management Peter Thurtell urged people to watch out for heat stroke or heat exhaustion.
Severe heatwave conditions are also forecast for South Australia’s northwest, northeast and Flinders regions with some areas expected to hit the mid-40s.
It will be another scorching day for the southern state after its capital nudged more than 41C on Tuesday afternoon, the first more than 40C day of the year.
Extreme fire dangers are also forecast for parts of the Pilbara coast on Jan. 24.
A cool change is set to develop later on Jan. 23 with a low-intensity heatwave lingering across the northeast by Sunday, the Bureau of Meteorology said.