Australia records its hottest day ever – and it's about to get worse

Australia has suffered through its hottest day on record with the Bureau of Meteorology revealing Tuesday’s average maximum temperature across the nation was 40.9 degrees.

Temperatures exceeded 45 degrees for much of the interior of Australia on Tuesday. At Ceduna on the west coast of the Eyre Peninsula in South Australia a maximum of 46.5 degrees was recorded.

The national average temperature of 40.9 exceeds the previous record of 40.3 set in 2013, based on preliminary results BoM meteorologist Diana Eadie said on Wednesday.

“This heat will only intensify further today [Wednesday],” she said.

“Southern and Central Australia will swelter with temperatures 8 to 16 degrees above average.”

The heatwave is being driven by an extremely hot air mass travelling across Australia from west to east.

Adelaide was sitting at 43.7 degrees at 3pm on Wednesday, after reaching 42.1 on Tuesday. The maximum temperature will again exceed 40 on Thursday and Friday. Ceduna on Wednesday reached 46.5 again.

Australia’s driest spring on record

Australia has endured its driest spring on record, setting the scene for a devastating bushfire season in which fierce blazes have swept across the country.

The bureau on Wednesday also confirmed spring was also the second-warmest ever recorded.

Rainfall was 62 per cent below average, making the spring of 2019 the driest since the previous all-time low in 1967, the bureau said in a special climate statement.

"The low rainfall added to pre-existing rainfall deficiencies and low soil moisture, exacerbating the meteorological and hydrological drought conditions and meaning forest fuels remained dry," the BOM said.

The average maximum daytime temperature was 2.41C above average, the second-warmest on record behind 2014.

Melbourne sizzles as heatwave moves east

The heatwave extended into Victoria on Wednesday, with Melbourne reaching 39.7 before 3pm and Hopetoun in northwest Victoria sitting on 42.6.

The extreme heat is moving east into NSW and the ACT. Canberra is expecting 40 on Thursday and Sydney 39.

In NSW, the heatwave will elevate fire risk as it moves through parts of the state still battling more than 100 bushfires on Thursday.

"We're looking at temperatures during the daytime that are around 10C-to-14C above average for this time of year," BoM acting NSW manager Jane Golding said.

"With the heat comes fires so we're expecting some particularly tricky days for the fire response on Thursday, Friday, Saturday and Sunday."

More records set to tumble during heatwave

The bureau expects temperatures in many locations to approach or even break December, and potentially, annual records.

Victoria could record its hottest December day on Friday if centres in the northwest such as Mildura and Swan Hill reach a forecast 47C.

"We're expecting a lot of December records to be challenged, particularly in northwest, north-central Victoria some parts of northwest Victoria may get very close to records for any time of the year," Climatologist Dr Blair Trewin said.

Mildura is forecast to swelter through three days in a row of 45C and above.

By 11.30 am on Wednesday, the border city had reached 38.1C.

"That's only happened once before in 1939 so it is certainly a very significant heatwave, particularly for December," he added.

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In western NSW, temperatures are expected to climb above 45 while Canberra is bracing for 43 on Saturday.

"For the ACT we're looking at five days in a row above about 37 degrees. Three of those days will be in the low 40s, so severe to extreme heatwave conditions," Ms Golding said.

Alice Springs is expected to reach 45 on Thursday, close to its hottest temperature of 45.6C, a record met twice last summer.

Parts of Queensland are still sweltering despite a cool change bringing relief to Brisbane after it hit 41.2C on Monday, its highest December temperature since 1981.

But the western town of Birdsville is forecast to remain in the mid-40s all week, peaking at 47C on Wednesday.

Heatwave conditions Australia’s biggest natural killer

As the mercury climbs, authorities are warning people to prepare for the hot weather.

"Extreme heat kills more Australians than any natural disaster and can affect anybody, but those most at risk are older people, young children and those with medical conditions," Victoria's State Response Controller Gavin Freeman said.

He advised people to stay hydrated, keep cool, never leave kids or pets in hot cars and check in on others who may be at risk.

Ambulance Victoria’s Director of Emergency Management, Justin Dunlop, said heatstroke symptoms should not be ignored.

“Heatstroke is a serious illness and requires immediate medical attention. If you experience symptoms including an extremely high body temperature, flushed dry skin, a rapid pulse, headache or disorientation, we ask you to call 000,” he said.

with AAP

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