The Mount Lofty Ranges are expecting hazardous bushfire conditions, just days before officially beginning the fire danger season on December 1.
The hot day comes after the warmest November night in nine years, with a low of 25.9 degrees this morning.
By 8:30am Central Time, the temperature was already tipping 30 degrees.
Districts under total fire bans until midnight due to severe conditions include Northwest Pastoral, Northeast Pastoral, Eastern Eyre Peninsula, Flinders Ranges, Mid North, Mount Lofty Ranges, Yorke Peninsula, Riverland, Murraylands and Upper South East.
Landowners in this area are instructed to adhere to local harvest codes of practice.
Duty forecaster at the Adelaide Bureau of Meteorology, Sam Connors told 891 Breakfast a cool change is expected to cross the state mid-afternoon and push NNW winds to cooler SW winds and bring a 16 degree overnight low with a possible 5 to 10mm of rain overnight.
A forecasted top of 41 degrees will be shared by Port Augusta, Roxby Downs, Leigh Creek, Tarcoola and Oodnadatta.
Renmark, Waikerie, Port Pirie, Coober Pedy, Woomera, Marla and Moomba are all expected to reach 40 degrees, with most inland centres expecting mid-to-high 30s and coastal areas low-to-mid 30s.
Stenhouse Bay will be the coolest location in the state, with an expected 23 degree.