Severe heatwave warning for four states as temperatures hit 40C

A scorching summer heatwave will continue to simmer across southern parts of Australia on Tuesday with temperatures expected to hit 40C in some areas.

Millions of Aussies packed onto crowded beaches on Christmas Day and Boxing Day this year to soak up the sun, but there's no end in sight just yet.

Severe heatwave warnings have been issued for Western Australia, South Australia, Victoria and Tasmania with temperatures 8 to 16 degrees above average.

Adelaide is on its way to a forecast maximum of 40 after sweating through a night where the mercury sank only as far as 27.4.

On Monday, The Bureau of Meteorology issued a heatwave warning for Victoria which will see temperatures of up to 37 on Tuesday. Melbourne expects a top of 37 — its hottest day since January 1 — while most of Tasmania, including Hobart, is due to rise to more than 30.

Canberra will also see the mercury surpass 30 after dipping to 11 overnight and Perth can expect a high of 27. Much of inland NSW is headed for maximums between 35 and 40 but coastal breezes will keep Sydney at about 28 degrees.

Urgent warning for most vulnerable

While some welcome sweltering conditions, severe heatwaves can be dangerous, particularly for older people, babies, children and pregnant and breastfeeding women.

The Bureau of Meteorology advises people to seek a place to keep cool, such as a home, a library, a community centre or a shopping centre.

And with temperatures soaring into the high 30s and low 40s, RSPCA South Australia is urging those with animals to take extra precautions as extreme heat puts them at severe risk of suffering health issues.

For domestic animals, RSPCA South Australia suggests allowing access to shelter from the sun throughout the day, and for them to be brought into air-conditioned spaces if possible. Multiple sources of water should also be available to animals.

Pet owners are advised to avoid transporting them in vehicles and not to leave them unattended in vehicles even if windows are down and the vehicle is parked in the shade. Dogs should not be put in trays of utes or trucks.

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Dogs should not be walked during the heat of the day, and if you cannot hold the back of your hand on the surface for five seconds, then it is too hot for your dog’s paws.

RSPCA South Australia is also encouraging people to support wildlife through the heatwave by placing shallow bowls of fresh, clean water in shady locations. If using a large container, place a rock in the water so small animals can climb out. Also, fill bird baths and consider having a sprinkler turned on during the heat of the day to enable birds to cool down.

Cool change expected

Heatwave conditions are expected to ease on Wednesday and Thursday following a cool change. Melbourne will experience cooler temperatures from around midday on Wednesday.

Further north, a severe weather warning remains in place for the Northern Territory across parts of the Barkly and Simpson districts. The slowly moving ex-tropical cyclone Ellie is bringing rainfalls totalling up to 300mm for some areas east of Tennant Creek, raising concerns of flash flooding.

Kalkarindji on the Buntine Highway copped 60 millimetres of rain in 30 minutes up to 1.32am on Tuesday.

"Although the system is forecast to temporarily weaken today, heavy rainfall and thunderstorm activity is expected to continue," a BoM statement said.

with AAP

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