From heatwaves to thunderstorms: What to expect on Christmas Day
South Australia is on alert as a heatwave continues to hit the state and temperatures hit the 40s. Photo: Getty
Australians in Perth and parts of regional Queensland and NSW have been told to expect extreme heatwaves and thunderstorms this Christmas.
Bureau of Meteorology senior meteorologist Jackson Browne told The New Daily Perth was in for an absolute scorcher of a festive weekend, with Saturday and Sunday slated to hit 42 degrees.
And the high temperatures will persist. Next week, the Western Australian capital is forecast to reach 33 degrees and higher every day.
A successive number of such very hot days are considered a heatwave.
“If we run the numbers back through time, the last time we saw extreme heatwave conditions in Perth was 25 years ago, back in December of 1996 through to January of 1997,” Mr Browne said.
“Perth does get hot in the summer, but this is unusually hot.”
Such conditions mean people can become susceptible to heat stress, which can lead to dehydration, exhaustion and the worsening of existing medical conditions.
Mr Browne warned that the extreme heat could also affect infrastructure, such as electrical systems and transportation.
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Elsewhere, there are reports of a tropical cyclone risk in northern Australia. But Mr Browne said was probably true for up to five months of the year.
“We do have an active monsoon trough, which is sitting over the northern regions of the Timor and Arafura seas, just north of Darwin,” he said.
“What we’ve seen overnight is a surge in the winds from the north-west, over Indonesia, and that’s going to push the trough south towards Darwin.”
Mr Browne said there was unlikely to be a huge spike in rainfall in the Tiwi Islands and Darwin, especially along the west coast of the Top End.
BOM is forecasting up to 20 millimetres of rain for Darwin on Friday. On Christmas Day, that jumps up to a possible 80 millimetres, with up to another 90 millimetres possible on Boxing Day.
Mr Browne said the weather bureau was likely to issue a severe weather warning later on Friday for heavy rainfall across northern Australia. But it was too early to call an official tropical cyclone warning.
“Embedded within this trough is a circulation and we’re monitoring the circulation for any possibility of development,” he said.
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In the country’s south-east, meanwhile, things are rather more settled.
Sydney and Canberra can expect some showers across the weekend, while Melbourne and Hobart can expect cool weather for Christmas and Boxing Day.
Adelaide is forecast is to top at 27 and 26 degrees across the weekend.
But from the mid-north coast of NSW north, easterly winds will bring some showers.
“Places like Brisbane, up to Fraser Coast, will see quite a bit of shower activity,” Mr Browne said.
“If we look at the Brisbane forecast, there’s a very high chance of rain right through Christmas to the 29th of December. So it’s going to be a very wet Christmas for them.”
Further inland – over central southern Queensland and the northern plains of NSW – there is a severe thunderstorm threat.
“That’s largely around rainfall, but you could possibly get some damaging winds or some large hail, but that’s on the lower probability side.”