Summer's first heatwave hits hard, putting energy regulator on notice

The first heatwave of Australia’s summer has arrived, and the high temperatures have put the national energy regulator on notice.

Temperatures across New South Wales, Victoria and parts of Queensland spiked on Wednesday, with parts of western Sydney approaching 40C.

The Bureau of Meteorology is forecasting “locally severe intensity heatwave conditions” across south-east Australia, in the east coast states and parts of South Australia.

Low to locally severe heatwave conditions also extend across the country’s tropical north, mainly through northern Western Australia.

And while the heat is expected to subside somewhat in Victoria on Thursday, relief could be a while off for other parts of the country, with heatwave conditions expected to persist until the middle of next week.

Low to severe intensity heatwave conditions are forecast for Thursday, with the hottest areas in the eastern parts of NSW where temperatures of 10C to 12C above average are predicted.

Sydney is forecast to reach 35 degrees, but western suburbs surrounding Parramatta and Penrith could reach 41.

A very weak cool change will hit NSW and southern Queensland on Friday, but the Bureau of Meteorology is predicting heatwave conditions will spread across the country after that, with “locally extreme” weather expected in parts of southern Queensland and December heat records predicted for western NSW.

In the western NSW town of Bourke, for example, the BOM expects seven consecutive days of 40C-plus temperatures from Wednesday, which would be the longest spell of those sorts of conditions since February 2009.

Sarah Fitton, an extreme weather meteorologist from the BOM, said over the weekend the heat would spread “across the country”, particularly in southern parts of Western Australia and South Australia.

“Broadly speaking along the south coast of the country we could see temperatures of 12 to 16 above average for December, so very hot conditions,” she said.

It is not clear when relief will arrive. Fitton said a high pressure system had been sitting in the Tasman Sea for “quite a while” and was combining with a low pressure system off WA to direct hot air from the northern parts of the country into central and southern Australia.

“There will be some relief mid next week but how much impact it will have on NSW and Queensland and when the heatwave might end is a little bit uncertain,” she said. “For parts of NSW there should be some relief but it’s not entirely certain if it will flush out all of that hot air.”

After widespread energy shortages and blackouts in some parts of the country dominated headlines last summer, the high temperatures have put the national energy regulator on notice.

Temperatures were expected to peak in the high 30s and low 40s in parts of Victoria and SA on Wednesday, which earlier prompted the Australian Energy Market Operator to a issue a lack-of-reserve notice there and in South Australia.

The notices advise of tightening of electricity supply reserves as a way of encouraging more generation to come into the market, but do not immediately indicate any impact to energy security.

Temperatures in Victoria are due to ease on Thursday, and Aemo cancelled that notice on Wednesday afternoon, saying that “based on current forecasts” it did not expect to face any energy shortfalls.

The regulator responded to shortages in the system last summer by building the amount of generation operating in the market and its availability throughout summer, as well as introducing a reserve of off-market generation to be operated in emergencies if needed.

As temperatures increased in South Australia last week Aemo called on the new Tesla battery for the first time, which delivered 70MW of stored wind energy into South Australia on 30 November.