Sydneysiders are sweltering through a scorcher with temperatures hitting 41C in parts of the city ahead of an expected afternoon change, when temperatures could plummet 15C.
The Bureau of Meteorology said New South Wales would on Tuesday bear the brunt of the pool of very hot air that sent temperatures in parts of South Australia and Victoria into the 40s on Monday.
Sydney’s main Observatory Hill weather station recorded 32C at 2pm after reaching 36C by 1pm. Temperatures reached 42.5C at 1.34pm at Sydney airport and exceeded 41C at suburbs including Badgerys Creek, Bankstown and Holsworthy by 2pm.
Penrith hit 41.6C by 2pm and was forecast to reach 42C later in the afternoon, as was Olympic Park in western Sydney.
Severe heatwave warnings were in place for large parts of NSW.
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“NSW will see the mercury shoot upwards today. Some of the hottest temperatures across the state will be across the Sydney basin,” the BoM senior meteorologist Miriam Bradbury said.
“Communities through the central-west slopes and plains will be some of the warmest in the country, along with the Sydney metro area.”
Dubbo, Parkes and Forbes were forecast to reach up to 43C on Tuesday.
A cool change was expected to bring relief later in the day, the senior meteorologist Angus Hines said.
“It will become what we call a bit of a southerly buster and shoot up that coast with a bit of ferocity, bringing some very strong winds and a very sharp temperature drop – and for Sydney, that’s forecast to be around 4pm,” he said.
“The temperature could plummet about 15C.”
More than 1,000 NSW residents were facing hot conditions without power due to outages caused by overnight storms. Ausgrid reported more than 1,200 sites were affected, with more than 400 Endeavour Energy customers experiencing blackouts.
While strong winds would deliver a welcome temperature drop, gusts could bring down trees and lead to further power outages, authorities said.
Wind speeds were expected to reach 40 to 60km/h along the coast and damaging gusts up to 100km/h were possible through parts of the Illawarra, Sydney metropolitan and southern Hunter regions.
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The change could also deliver potentially severe thunderstorms, mostly around the eastern ranges and towards the east coast.
“If that happens, those severe storms could bring damaging wind gusts, large hail or heavy rainfall that could lead to flash flooding,” Hines said.
“So it could be a very active day of weather across NSW, starting with the heat and then coming in with the storms and the sharp temperature drop and the powerful winds.”
In Victoria, the state’s emergency warning service, VicEmergency, issued a number of alerts to communities in the west due to out-of-control bushfires.
Authorities advised people in Strachans, Victoria Point and Victoria Valley to leave immediately, and those in Dimboola and Wail to take shelter.
On the other side of the country, heatwave conditions experienced last week were rebounding, with temperatures forecast to be 4C to 12C warmer than the typical January averages across western parts of Western Australia – and up into the 40s over the next couple of days.
While some states were enjoying milder conditions on Tuesday, northern Queensland could expect persistent wet weather to continue throughout the week, with the heaviest and most persistent falls expected between Cooktown and Ayr.
Later in the week and into the weekend, Queensland could see its first tropical cyclone this summer, Bradbury said. A low pressure system forming over the Coral Sea and Gulf of Carpentaria posed a low-to-moderate chance of becoming a tropical cyclone.
Australia’s land surface has warmed by 1.5C since 1910, according to the BoM, with the climate crisis making heatwaves longer and more intense, and increasing the number of extremely hot days.