Australia Weather News

Australia will be sweltering next week, but the same wind system that could push mainland states into record territory will have an entirely different effect on Tasmania.

Perth is enduring an unprecedented heatwave, and as that hot air makes its way east, temperatures across the country are expected to soar.

One Bureau of Meteorology (BOM) scientist suggested Australia's highest ever recorded temperature — 50.7 degrees Celsius, recorded at Oodnadatta in South Australia — could be topped.

But while mainland residents jostle for shade and make excuses to visit their neighbours with pools, Tasmanians will still be enjoying light jacket weather.

Same wind, different effect

BOM meteorologist Alex Melitsis said there were two main climate factors impacting the mainland.

The first is the positive Indian Ocean Dipole, which relates to the sea surface temperature across the Indian Ocean.

"The waters over parts of the eastern Indian Ocean are a little below average, which means there's less moisture around for rainfall over the eastern part of the mainland," Mr Melitsis said.

The second factor is the negative Southern Annulare Mode, which relates to the "position of the band of strong westerlies which flow around Antarctica".

"That's more northwards than usual," Mr Melitsis said.

He said the winds were bringing cooler air over Tasmania, but those same winds were "dragging that hot continental air over the mainland".

"For Tasmania, those strong winds have brought much cooler than average temperatures," he said, adding that so far this December, temperatures had been about 2C to 3C below average.

Next week, a "blocking high pressure system" will develop off Australia's east coast, allowing extreme heat to build over the mainland.

But in Tasmania "we'll see an area of high pressure sit over the state, so we're kind of being shielded from very hot, continental northerly winds," Mr Melitsis said.

But Australia's southernmost state has not escaped the heat altogether.

What will the weather be like in Tasmania next week?

Mr Melitsis said Tasmanians could still endure temperatures into the 30s.

"We will see the heat gradually build but we're not seeing that exceptional heat from the mainland," he said.

He said Hobart would start the week in the low to mid 20s, and gradually build up on Tuesday and Wednesday, with mid 20s in the city — but 4C to 5C warmer in northern suburbs which do not get the sea breeze.

The hottest day in Tasmania next week will be Friday, but pinpointing the temperature will be "tricky", Mr Melitsis said.

"We do see a cold front approach Tasmania on Friday, [but] we're uncertain of the timing.

Currently, the forecast is for 29C for Hobart on Friday, with temperatures climbing to 31C or 32C in the northern suburbs.

But Mr Melitsis said it could be warmer if the front crosses earlier than expected.

Tasmania subject to different weather patterns

There's nothing that quite raises the ire of Tasmanians than being lumped in with the mainland when they're geographically far apart, or forgotten altogether.

(On Wikipedia, there is even a page titled "Omission of Tasmania from maps of Australia" which notes "such omissions often provoke outrage from Tasmanians".)

Mr Melitsis said the upcoming week of unseasonal hot weather was another reminder that the "weather patternsaffecting Tasmania are very different to those affecting the mainland".

"We're not subject to the same weather patterns that the mainland will be, so the heatwave will be less severe," he said.

ABC