Australia often dominates heat temperatures in summer given that rival southern hemisphere sites are mostly in South America and South Africa where readings above 40 degrees are not so common.
The world’s hottest places in the 24 hours to 11am (AEDT) on January 16:
- Tarcoola (Australia) 49.1°C
- Port Augusta Aws (Australia) 49°C
- Woomera Aerodrome (Australia) 48°C
- Olympic Dam Aerodrome (Australia) 47.9°C
- Hay Airport Aws (Australia) 47.8°C
- Oodnadatta Airport (Australia) 47.7°C
- Marree Aero (Australia) 47.6°C
- Coober Pedy Aws (Australia) 47.5°C
- Warburton Airfield (Australia) 47.3°C
- Ivanhoe Aerodrome Aws (Australia) 46.9°C
- Wilcannia Aerodrome Aws (Australia) 46.6°C
- Leigh Creek Airport (Australia) 46.3°C
- Wulungurru (Australia) 46.2°C
- Moomba Airport (Australia) 46.1°C
- Yulara Aws (Australia) 46.1°C
Jacob Cronje, a senior meteorologist with Weatherzone, said he “wouldn’t be shocked” by a 50-degree reading during the current spell given the scale and intensity of the heat.
“Certainly the duration of this event and the spatial extent of the heatwave across the southern half of Australia seems to be quite significant,” he said.
“By the end of the week, we should see many records broken across NSW,” Mr Cronje said, adding that northern Victoria may have to rewrite the records too.
Australia has only posted three days above 50 degrees using standardised equipment, the most recent being in February 1998 when Mardie in WA reached 50.5 degrees. The other two occurred in January 1960 when Oodnadatta Airport in SA reached 50.7 and 50.3 on consecutive days, the bureau said.
Much of the Riverina and most of Victoria’s north can expect 45 to 47 degrees on Wednesday, with little relief in daytime maximums until Friday or Saturday. By late Wednesday morning, all the mainland states had reached 40 degrees.
Both Melbourne and Sydney cities will be spared the worst of the heat, but inland suburbs would be a lot warmer.
Even so, high humidity, particularly in the harbour city, would make for some very uncomfortable nights, particularly Friday into Saturday, Mr Cronje said.
Minimum temperatures for Saturday morning of about 24 degrees for coastal Sydney suburbs would likely feel several degrees warmer.
For Canberra, temperatures may reach 40 degrees for four days in a row, a series not recorded before for the nation’s capital. There were no days of 40 degrees recorded in Canberra between 1973 and 1998, according to the bureau.
Health authorities is several states have issued warnings for people to take care of themselves, their relatives, neighbours and their pets as heatwave impacts can build over several days.
An added threat in Sydney will be the high ozone air pollution expected across the city in coming days.
Richard Broome, director of environmental health at NSW Health, said “ozone can irritate the lungs, and that people with asthma need to follow their Asthma Action Plan and have their relieving medication with them”.
“Ozone levels are higher outdoors than indoors, and generally highest in the afternoon and early evening, so limiting time outdoors during the heat of the day and in the evening helps people to not only keep cool but to limit their exposure to ozone pollution,” Dr Broome said in a statement.
Those most at risk were residents with asthma and other respiratory diseases such as chronic obstructive pulmonary disease, and anyone experiencing severe respiratory distress should seek immediate medical help, the statement said.
The coming cool change will shift a blocking high in the Tasman Sea, which has helped inland temperatures build up in recent weeks.
Peter Hannam writes on environment issues for The Sydney Morning Herald and The Age.