Scorching weather on Saturday morning as mercury rises across South Australia, but a change is on the way

South Australia has sweltered through a sticky November day, but relief is around the corner.

South Australia has been hit with the full force of mercury today but conditions will dramatically change as the hours go on.

The Bureau of Meteorology said in metropolitan Adelaide on Saturday the mercury will climb to an expected high of 37C in the city – tipping 40C in other parts of SA – before a change sweeps in, with the chance of a shower or two developing.

But on Sunday, it will be a significantly cooler 21C, with a possible shower.

Senior meteorologist Mark Anolak said South Aussies should prep for “very hot conditions” and be mindful of the “hot, gusty winds” on Saturday.

“The combination of the heat with the dry northerly winds, which will be getting up to the order of 50 to 60km/h is creating extreme to catastrophic fire danger across parts of South Australia,” he said. “As a result, the CFS has issued a total fire ban for 10 districts today.”

“But we are also expecting a dramatic change in conditions later this evening and into tomorrow, with a risk of rain and thunderstorms following as well.”

South Australia’s surf sports superstars, 20-year-old Maguire Reid and 17-year-old Aiden Carberry. Picture: Brett Hartwig

Meanwhile, firefighters warn of the most dangerous weather conditions seen so far this year.

Catastrophic ratings were declared for the Eastern Eyre Peninsula and Yorke Peninsula, with CFS chief officer Brett Loughlin pleading for South Australians to avoid “high-risk activities” in all affected areas.

These include driving heavy machinery in paddocks and around fuel loads, as well as using angle grinders, which allegedly caused a bushfire at Penfield two weeks ago.

Extreme danger ratings have also been forecast for the West Coast, Lower Eyre Peninsula, Flinders Ranges, Mid North, Mt Lofty Ranges, Murraylands, Riverland and Upper South-East.

Fire bans have been enforced in all the above mentioned regions.

Mr Loughlin said firefighters would be on “high alert” because of strong winds and low humidity, meaning “any fires that start will be challenging for firefighters to achieve operational success”.

CFS chief officer Brett Loughlin warned residents in declared areas to prepare their bushfire survival plans as soon as possible. Picture: NCA NewsWire / Kelly Barnes

“The message to South Australians is clear – take the weather (on Saturday) very seriously,” he said.

“If you have not yet prepared your bushfire survival plan, do so now. It is not too late.”

Mr Loughlin urged people to rely on multiple information sources rather than just one.

He also said landowners should maintain close watch on recently-completed controlled burns which could “flare back into life”.

Fire bans were launched on Friday, two weeks earlier than usual this year, with temperatures predicted to be hotter and drier this summer.

Meanwhile, in Murray Bridge, Saturday is expected to reach 40C, with a sunny morning before becoming cloudy, with a shower or two and dipping to 24C on Sunday.

Whyalla is also expected to be a humid 40C on Saturday, before dropping to 24C.

Kadina should see a high of 38C on Saturday before cooling down to 23C.

Further north, Kadina is also due to hit 40C on Saturday before easing to 28C, while Oodnadatta is heading for 41C on Saturday and 28C on Sunday.

Even Victor Harbor won’t escape the heat, with 37C on Saturday followed by a refreshing 21C.