Australia braces for its most intense heatwave in six years
Parts of southern Australia are set to endure days of extreme heat above 45°C, as a powerful heatwave sweeps across the country this week.
The Bureau of Meteorology has warned this could be the most significant heat event for south-eastern Australia since 2019–20, with severe to extreme heatwave alerts stretching more than 3,500km — from north-west WA to north-east Tasmania — between Wednesday and Saturday.
What to expect
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Victoria, South Australia and south-east NSW could see temperatures 8–16°C above average
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Port Augusta may hit 46°C, with three days above 45°C
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Mildura and Echuca forecast for multiple days at 44–45°C
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Adelaide: up to 41°C
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Melbourne: up to 41°C
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Sydney: forecast 39°C on Saturday
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Canberra: several days between 36–39°C
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Even Tasmania faces unusually hot conditions, up to 10°C above average
Meteorologists say the danger isn’t just the daytime heat — overnight temperatures will also stay high, offering little relief and increasing health risks.
Fire danger escalating
The prolonged heat, combined with strong winds and dry lightning, has raised concerns of extreme fire danger, especially across South Australia and Victoria on Friday, extending into NSW by the weekend.
Relief on the way
A strong cold front is expected to bring a sharp cool change from Saturday, with temperatures dropping 10–15°C in a single day — but not before peak fire risk hits.
Wednesday to Friday is the peak of heatwave conditions, with parts of Victoria and NSW under extreme heatwave warnings. Photo: ABC News
“January is one of the hottest months of the year, but there are a few places that are at least approaching or getting pretty close to records, particularly in north-west Victoria,” he said.
The biggest deviations from normal, however, will be further south.
Coastal parts of SA and Victoria, where temperatures generally average the high 20s, are also forecast to reach or near 40C for several days in a row.
Adelaide, for example, is forecast to reach 41C on Wednesday and 39C on Thursday.
Melbourne is not far behind with a forecast top of 41C on Wednesday and 38C on Friday, with a brief drop in temperatures forecast on Thursday for coastal parts of SA and Victoria.
The heat will progress further eastward by the weekend, with Sydney also forecast to reach a top of 39 on Saturday and Canberra hitting temperatures between 36-39C for several days in a row.
Though not as exceptional as the other states, Tasmania is also looking at temperatures much warmer than usual for this time of year, with daytime temps 6-10 degrees above average on both Wednesday and Thursday.
‘Block’ triggers multiple days above 40C
While temperature spikes into the 40s are not uncommon for January, Narramore said what set this event apart was how long the high temperatures were lasting – especially for the south coast.
“Normally … we’ll see temperatures for a day or so spike into the mid 40s,” he said.
“But now we’re looking at three, and in some areas four, consecutive days where the temperature will be sitting somewhere between 10 and 15 degrees [above average] through inland parts of south-eastern Australia.”
Narramore said the culprit for the long-lasting heat could be found to the east of Australia, where a strong high-pressure system was causing a jam in the flow of weather.
This was preventing the heat from moving swiftly from west to east, instead leading to days upon days of warmth.
“So it’s just going to be hot, it’s going to be sunny, and it’s going to sit there for three days before that high weakens in the Tasman Sea, and then a stronger front comes in and pushes that trough through south-eastern Australia,” he said.
Extreme fire danger ahead of cool change
A cool change is on the way by the weekend, with a cold front set to see the mercury plunge by 10-15C in the space of a day from Saturday.
Ahead of its arrival, however, fire danger is likely to increase with the cold front helping to whip up gusty winds and the potential for dry lightning.
Narramore said widespread extreme fire danger was likely on Friday across South Australia and Victoria, moving into eastern Victoria and southern and eastern New South Wales on Saturday.
“Thursday, we have the chance of thunderstorms through central and eastern Victoria,” he said.
“Then, unfortunately Friday, we could see quite a bit of dry lightning through Victoria and Tasmania ahead of that front.
“So Friday is probably … the main danger day.”