Sydney braces for 40C at lunchtime before southerly buster brings severe storms | New South Wales

The heatwave conditions that swept across Australia during the long weekend are forecast to shift states as a cool change brings the risk of severe thunderstorms, including large hail stones and damaging winds.

The Bureau of Meteorology said New South Wales would bear the brunt of the same pool of very hot air that sent temperatures in parts of South Australia and across Victoria into the 40s on Monday,

Most of NSW, including Sydney and some of its western suburbs, could expect temperatures in the high 30s or low 40s on Tuesday before the cool change shifts up the coast, 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 … and the wind will also pick up and become very strong.”

The change could also spark 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.”

On the other side of the country, heatwave conditions experienced last week are 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 in the next couple of days.

The tropical north would also be a focus for forecasters in coming days, Hines said, with rainfall intensifying across northeast Queensland.

“There is likely to be a heavy rain warning issued for some parts of the coast, mostly between Cairns and Townsville,” he said.

“When we start looking towards next week, we see the potential for tropical cyclone development for a few areas across northern Australia.”

This includes the Coral Sea off the north-east Queensland coast, in the Gulf of Carpentaria and potentially off the north coast of WA.

“There’s still quite a few days until that’s likely to happen, but certainly, anyone living in the northern latitudes of Australia should be keeping an eye on the forecast and the warnings as we approach the end of this week,” Hines said.