Hottest start to summer in 24 years
The "extreme heat" affecting south east Australia will likely send temperatures in Melbourne soaring to 38C today, 14 degrees above average, and up to 42C in regional areas.
The Bureau of Meteorology (BOM) has said the state will record its hottest start to summer in 24 years.
DELUGE IN QUEENSLAND
In Queensland, ex-tropical cyclone Owen continues to cause concern as it heads towards the coast bringing gusty winds and driving rain.
The south east of the state won't be hit but further north it's going to be a washout. Mackay could get as much as 100mm of rain on Friday and then from 50 - 150mm on both Saturday and Sunday.
"It will get windier and windier and the rainfall will be ramping up on Saturday afternoon and that's likely to lead to flash flooding bringing an absolute deluge," said Sky News weather meteorologist Tristan Myers.
"The one thing to note is the exact location (of the rain) is uncertain but it's likely to be somewhere around the central coastline from around Proserpine/Whitsundays down to Yeppoon region."
Brisbane will have a possible shower and some cloud throughout the weekend with highs of around 25C.
Elsewhere, Sydney will see a pleasant 26C on Friday and then 28C on the weekend with lots of sun. Perth will hover around the 30C mark on a sunny weekend. In Darwin, temperatures will reach 35C with possible showers and storms.
A DIFFERENT STORY ACROSS THE NATION
Adelaide is also likely to hit 38C, after pushing past 40C yesterday making the Test between Australia and India a punish.
It could not be more different in Queensland where more than 300mm of rain could fall in some areas in what is being called a "deluge".
The temperatures in Victoria have prompted a warning from health authorities for some areas.
"The chief health officer has issued a heat health alert to notify you of forecast extreme heat conditions at or above heat health temperature thresholds," the government said in a statement.
Western parts of the state, such as Mildura, Horsham and Swan Hill, are all forecast to surpass the 40C mark. Regional parts of SA could hit 42C including Murray Bridge and Whyalla.
The Victoria Country Fire Authority has imposed a total fire ban for the districts of the Mallee, Wimmera and the Northern Country.
A bushfire in Buninyong near Ballarat was brought under control last night but a watch and act warning is in place for Durham Lead, Grenville and Scotsburn.
The Victorian Government has labelled the conditions "extreme heat" and has urged people to hydrate and keep cool.
RELIEF IN SIGHT
The heat is due to a high pressure system causing northerly winds to suck dry heat from the desert down towards the southeast.
But there is an end in sight for the two capitals, said the BOM's Chris Godfred: "There is a change coming, every heatwave has to end eventually, however this is not a very strong change.
"We should see it reach Melbourne very late on Friday night so unfortunately we're not going to get real relief from the heat until Saturday."
The heat should ease in Adelaide later this afternoon. That wind change, however, could hamper efforts to dampen a bushfire on Kangaroo Island.
Adelaide should see its maximum high drop 12 degrees between Friday and Saturday reaching 28C on the weekend. Melbourne will only reach 27C on Saturday.
Inland areas will also see temperatures fall - but only modestly. Mildura is forecast to reach 39C on Saturday, just 3 degrees lower than Friday. And the border town doesn't look likely to see highs lower than 33C all week.