Dangerous dust storms have been whipped up across South Australia as wild weather lashed the state.

The storms began in the far west and have gradually moved east during the day.

Conditions were so volatile on the Eyre Peninsula, SA Power Networks made the decision to cut electricity supply to more than 50,000 customers. Gusts as high as 98km/h were recorded at Port Lincoln.

Picture taken from Hill Bank in Adelaide. Picture: Jace Koesling (Nine/Supplied)

"Safety is our priority and with the weather conditions in Port Lincoln today, it was required to temporarily disconnect the power," the company said.

"It is crucial we undertake such work to keep our community safe."

mages and videos posted on social media showed the thick dust whipped up from parched farming land and scrub as wind gusts hit close to 100 km/h.

Dust storms reduced visibility in some areas to only a few metres, including along major roads.

The Augusta Highway in the state's mid-north was closed by police as a safety measure.

One motorist who sent footage from on the road to Nine News can be heard saying "Just pulled out of (Port) Wakefield, I wish we'd stayed there."

"You just cannot move, the cars are all pulled up on the side of the road and it's the worst dust storm I have ever seen," he goes on to say.

Tom Boeck from the weather bureau said the dust storms were "widespread" over agricultural areas.

He said today's conditions were rare for this time of year.

"Normally we would have had some rain to dampen the soil somewhat."

Yesterday authorities had warned today's heat and wind would create dangerous fire conditions.

Dust swept across the state. (Nine/Supplied)

North of Port Wakefield. Monet Butler (Nine/Supplied)

Ahead of the change, temperatures climbed into the mid-30s in some centres and 32.6C in Adelaide.

The unseasonably hot and dry conditions prompted the Country Fire Service to declare severe bushfire conditions in eight districts, from the west coast to the lower southeast.

The CFS said it had also moved to extend the bushfire season across much of the state.

Chief officer Greg Nettleton said the two-week longer season was a reflection of the continued risk which would remain until there was substantial rainfall.

"We would require rainfall of more than 180mm, combined with milder autumn conditions, before we are likely to see a reduction in the risk in many areas," Mr Nettleton said.

"In many areas, trees and bushland are stressed due to the hot, dry summer."