Temperatures this week will soar above 40 degrees in some areas

Get set to swelter with 40-plus degree temperatures forecast for some areas until well into the week.

There will be no relief from heatwave conditions until southerly winds arrive in Adelaide on Wednesday afternoon, the Bureau of Meteorology has forecast.

The city reached a maximum of 32.2 degrees at 12:30pm Saturday, less than the 34 degrees predicted, but the Bureau stood by a dire forecast for the rest of the week which includes 40-degree-plus temperatures in the far north.

The next three days are predicted to bring Adelaide maximums of 36 degrees, 37 and 34 before south to south-westerly winds of 20 to 30 km/h keep Wednesday to a maximum of 31 degrees and Thursday 27.

And regional South Australians will be hit with far higher temperatures over the next three days.

To protect the homeless Human Services Minister Michelle Lensink has declared a “code red” from Sunday to Thursday.

The declared areas are Clare, Port Augusta, The Riverland and South East, with Eyre Peninsula likely to be less afflicted.

After reaching 38 degrees on Saturday, Port Augusta will be hit by 40 degrees, 42 degrees and 39 degrees over the next three days.

In Mt Gambier it will be 36 degrees on Sunday and Monday and Port Lincoln milder with 31 degrees on Sunday and 34 on Monday.

Coober Pedy was 38 degrees on Saturday and will be over 35 degrees for all of next week.

Ms Lensink said anyone distressed during the heatwave should contact Homelessness Connect on 1800 003 308.

Australia's "heat engine" is about to crank into life sending summer temperatures soaring. Picture: BOM.

“In these type of conditions it is important that people stay cool and keep hydrated,’’ she said.

The heatwave will strike as the Bureau also revealed in its Annual Climate Statement — the official summary of the previous year — that 2020 was the fourth-warmest year on record for Australia.

The nation averaged mean temperature for the year 1.15 °C above the 1961–1990 average.

Mean annual maximum and minimum temperatures were above average for all states and the Northern Territory.

But in the Murray – Darling Basin, southern water storages saw significant increases during 2020 – rising from 36.8 per cent in March 2020 to 68.8 per cent at the end of November.

BOM senior climatologist Dr Lynette Bettio, said the mean Australian temperature for the 10 years from 2011 to 2020 was the highest on record, at 0.94 degrees above average, and 0.33 degrees warmer than the previous 10 years.

But she said annual rainfall was above average across parts of South Australia between the Flinders Ranges and Lake Eyre.

“South Australia’s rainfall was close to average across large areas of the state in 2020, with several very dry months offset by a much wetter than average end to winter and start of spring,’’ Dr Bettio said.

“Both mean maximum and mean minimum temperatures were warmer than average across the west of SA and parts of the north; close to or cooler than average for much of the south and east.

“Twenty twenty had several very warm months, including the state’s warmest November on record, but South Australia also had its coolest May since 2006.

“Rainfall was close to or above average at all sites across Adelaide and the Hills.

“Both daytime and night-time temperatures for 2020 were within 1 degrees of average at most Adelaide sites.”

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