Sydney swelters though hottest day of the year so far

Sydney has had its hottest day of the year so far as multiple states swelter through heatwave conditions with stifling temperatures expected to continue over the coming days.

On Sunday it hit 38 degrees at the airport and further west in Penrith.

At 8pm it was still 30 degrees in Sydney's CBD, nudging over 31 degrees at the airport and 33 degrees in Penrith.

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This week's forecast

Sydney is set for 25 degrees on Monday and Tuesday, increasing to 34 degrees on Thursday.

After a cooler 20 degrees on Monday, the crowds at the Australian Open in Melbourne will bask in 29 degrees on Tuesday and 33 degrees on Wednesday.

Brisbane's hottest day will be Monday with 37 degrees expected before it cools a little.

Adelaide is set to roast in 39 degrees on Tuesday with it staying hot throughout the week.

Perth will be sunny with temperatures over 30 degrees, peaking at 33 degrees on Thursday.

The Bureau of Meteorology has predicted temperatures will reach 50 degrees in outback parts of Western Australia.

In the Pilbara, temperatures reached 47 degrees on Saturday, more than six degrees above the average January maximum.

Queensland is bracing for its second tropical cyclone in the space of about a month, with a low-pressure system expected to develop into a cyclone in the Coral Sea and likely cross the coast next week.

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The temperature is forecast to reach 48 degrees over the next three days in the area.

Australia's highest temperature on record of 50.7 degrees was logged at the Pilbara's Onslow Airport in January 2022.

Extreme heatwave conditions will gradually ease from early next week, while severe heatwave conditions will continue into early next week before easing mid-week.