Doctors are encouraging Australians to be alert to the signs of heat-related illness this weekend as searing temperatures are forecast for a large part of the nation.
Parts of the ACT, NSW, South Australia and Victoria will experience the 40C temperatures that had many West Australians sweltering this week.
Healthdirect chief medical officer Dr Nirvana Luckraj offered advice on preventing an emergency.
"The best way to prevent heat-related illness is to drink plenty of water and to stay as cool as possible," she said.
"Heat-related illnesses include dehydration, heat cramps, heath exhaustion, a worsening of existing medical conditions and in the worst cases, heat stroke."
Bureau of Meteorology senior meteorologist Angus Hines said the very warm weather that had affected Western Australia this week was moving to the east of the country.
"Most places will be getting a step warmer on Sunday," he said.
Some parts of South Australia were forecast to be 12 degrees warmer than usual, Mr Hines said.
The hottest parts would be in the east and south-east of the state. Renmark, close to the Victorian border, is forecast for 44C on Sunday.
People in Adelaide can expect temperatures in the low to mid-30s throughout the weekend.
Staff at the Women's and Children's Hospital in North Adelaide urged people to avoid sun exposure after an increase in people suffering the effects of heat.
Doctors and nurses have treated 15 patients for severe sunburn in recent weeks.
They encouraged people to use sunscreen, wear a hat, stay hydrated and avoid going out during the hottest part of the day (10am to 4pm).
In Victoria, people in some parts of the state can expect their warmest day on Sunday, since February 2023.
Melburnians are set for a 37C high on Sunday, but Mr Hines said a wind change due in the early afternoon could influence this.
"The timing of that wind change is crucial to the top temperature. If it comes through in the morning, it will be cooler than 37 degrees."
Mildura in Victoria's west is due for 43C on Sunday.
The Mildura Lawn Tennis Club held its weekend play on Saturday morning to avoid the Sunday conditions.
Ladies captain Brenda Hornsby was happy with the change of plan.
"I've had a a good game of tennis today so if I can have a nice quiet day in the air conditioning tomorrow, a bit of time in the pool, that will be it," she said.
For NSW, it's a repeat of heatwave conditions.
Mr Hines said parts of the NSW interior and west would have temperatures as high as 44C on Sunday.
"Most of western NSW did have heatwave conditions in January. So a lot of these places that will have 43 and 44 degrees were higher than that a few weeks back," he said.
Temperatures in western Sydney are forecast to reach 39C on Sunday and Monday.
Those on Australia's west coast have enjoyed some relief following heatwave conditions.
People in Perth have a forecast maximum of 31 degrees for Saturday, following two days of extreme temperatures. This included the Swan Valley in Perth experiencing a record 45.1C on Thursday.
Conditions will remain hot in the north of the state.
Marble Bar is forecast to reach 47C on Saturday and 46C on Sunday, while Broome is forecast to hit 34C on both days.
