If you think this has been the hottest April week of all time, you are not far off.
All-time temperature records for April were set at both Karoonda and Lameroo on Tuesday as the mercury reached 38 and 39.1 degrees, respectively.
With a maximum of 38.3 in Murray Bridge, Monday was only the third April day to pass 38 there since the high mark of 39.2 degrees was set in 1986, according to the Bureau of Meteorology.
The others were in 2005 – the day the previous record was set at Karoonda – and 2014.
The past few days have been just as hot elsewhere around the region, reaching into the mid-30s even at Strathalbyn and Meningie.
Natural Resources SA Murray-Darling Basin's network of weather stations recorded more high 38s at Caurnamont, Lowaldie, Sherlock, Wanbi and Wilkawatt on Tuesday.
One of the few places one could find relief was the aptly named Mount Pleasant, where the temperature topped out at a relatively frosty 33.7 degrees.
A supervising meteorologist at the bureau, Paul Lainio, said the conditions were due to a ridge of high barometric pressure to the east of South Australia and a low-pressure trough lying off the coast.
"The western flank of that high is pushing hot, dry northerly winds right down to that trough, so right down across all of South Australia effectively," he said on Wednesday morning.
"That low pressure trough is expected to move inland later today (Wednesday) across the Eyre Peninsula; it's expected to finally reach the Adelaide area during this evening, and then into the eastern parts of the state later on tonight.
"As that low-pressure trough moves through, we expect some cooler conditions."
He said winds would increase, especially along the southern coast, on Thursday; followed by a vigorous front and rainfall of up to 20 to 40 millimetres in the Adelaide Hills on Friday.
Temperatures are forecast to fall into the mid-20s for the end of the week.