Southern parts of the country are about to swelter through a heatwave as temperatures are expected remain well above 30 degrees into next week, while heavy rain hits North Queensland.
Meteorologist Dean Narramore said Melbourne and Adelaide saw temperatures in the high 30s yesterday.
"In Melbourne this morning, it is gloomy almost, doesn't look hot but it will be once the cloud clears later this afternoon," Narramore told Today.
"We're expecting 38 degrees or so around Adelaide and 37 degrees in Melbourne.
Regional areas are expected to hit 40 degrees.
"Once the cloud clears, southern Victoria will get into the high 30s. Then 41 at Swan Hill, Mildura and even hotter in inland parts of South Australia."
A cool change is expected overnight for Adelaide and Melbourne coastal areas but then it will heat up again on Monday and Tuesday.
Tasmania is also having its own heatwave with Hobart expected to hit 30 degrees today and Tuesday.
Meanwhile in North Queensland, a severe weather warning has been issued for Tully through to Mackay.
About 300mm of rain fell yesterday and another 200mm fell overnight.
"Rain is continuing to fall and forecast to fall over the next 48 hours," Narramore said.
"Flood watches are also issued so we're likely to see flash and riverine flooding become a bigger concern through the weekend into early next week."
Brisbane is expected to hit 27 degrees today.
Sydney will be overcast and will peak at 26 degrees today.
Perth is 32 degrees today and is expected to maintain low 30s throughout the week.
Darwin will be 33 degrees with storms throughout the week.
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