Health warnings as states braced for extreme heat

A public health warning has been issued in Adelaide as a heatwave moves east across from Western Australia, with December temperature records in the state expected to be smashed.

Today is expected to the first of four brutal days of 40C-plus temperatures across South Australia.

The north and western parts of SA will be hit the hardest.

Adelaide is expected to hit 44C by Friday while Oodnadatta will have three consecutive days of 47C.

Hospital staff across the state are braced for a rise in presentations related to heat-related illness.

Emergency services are also on high alert over the threat of bushfires.

Meanwhile, temperatures across some parts of Queensland are expected to reach 10 degrees above average for this time of the year.

Ipswich and  Gatton are both expected to reach 43C but the heat will be felt right across the south east. Brisbane is expected to push 39C.

However, there is relief on the way with a south-easterley change bringing cooler air across the south east of the state from tomorrow.

Sydney will be cooler today but the mercury will rise to a maximum of 36C by Thursday.

Likewise, Melbourne will reach a top of 22C today but temperatures could push close to the 40C mark by Wednesday, and again on Friday, with 41C forecast.

Perth will reach a top of 36C today with areas of smoke haze.