Surging temperatures and thunderstorms on the way for multiple major cities

A mass of hot air is about to sweep across Australia, sending temperatures surging in most parts of the country this week.

Perth reached 40 degrees Celsius on Sunday, when the mass of hot air hit the nation's western shores.

Now it is headed east towards other capital cities including Adelaide, Melbourne, Hobart, Canberra, Sydney and Brisbane.

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Temperatures are expected to continue to climb in Western Australia today as the heat spreads towards the south.

Weatherzone predicted the mercury could top out at 46 degrees to the north of Eyre this afternoon.

Tasmania will also get a brief blast of hot air today.

Temperatures in Hobart are forecast to reach 29 degrees today, though the city should cool off by tomorrow.

Warm conditions will last a little longer in the state's north, where Launceston will enjoy sun and temperatures in the high 20s until Friday.

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In South Australia, temperatures are expected to hit about 35 degrees in Adelaide today and jump to 39 degrees tomorrow.

Sweltering conditions should ease from Friday into the weekend.

NSW and the ACT are expecting similar conditions, with the heat expected to hit this afternoon in Sydney.

The harbour city will enjoy temperatures of up to 27 degrees today, then highs of up to 35 degrees for the rest of the week.

It will be even hotter in NSW's western parts, where temperatures could approach 40 degrees on Friday.

Canberra will also enjoy a sunny end to the week, with temperatures forecast to hover in the low to mid 30s for the next few days.

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Victoria will cop a heat blast on Thursday, with highs of up to 40 degrees predicted for parts of the state's north.

Melbourne is forecast to hit 37 degrees the same day and the hot weather will persist through to Friday.

Queensland will also see temperatures rise this week, with highs in the low- to mid-30s from Friday.

Storms are also expected across parts of the country as the hot weather sweeps through.

Expect rain and stormy weather across central Australia through Thursday, and in southeastern Australia from Friday.

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