The Bureau of Meteorology has issued a severe weather warning for a large area stretching from the northwest of the state to the coast of the Eyre Peninsula.

An upper low-pressure system and an associated trough are expected to move east on Friday and over the weekend with precipitation of up to 120 millimeters.

There is also the possibility of thunderstorms and harmful winds.

Regional cities that may be affected include Ceduna, Marla, Coober Pedy, Roxby Downs, Marree and Woomera, while flood warnings have also been issued for Flinders Ranges.

“Rainy weather can cause dams and widespread flooding. Roads can be affected, which can disrupt travel and transportation. Communities can be isolated,” BOM said.

SES urged people living and traveling through the affected area to remain vigilant, monitor local conditions and plan ahead.

“If people are camping, they should avoid setting up their tents or parking vehicles in and around streams and instead seek higher terrain until this weather event is relieved,” said Chief of Staff Sara Pulford.

“People also need to be aware that it does not have to rain where they are because they can be affected by river currents caused by rain upstream.

“Motorists should be on high alert for floods, drive according to the conditions and always avoid driving through floods.

“Flood water can rise rapidly, and it can take as little as 15 centimeters of flood water for a vehicle to become unstable, lose traction and flush away.”

Despite the expected flood in some parts of SA, Adelaide is expected to miss most of the rain.

The city may have up to 20 mm on Sundays with several minor falls possible on Saturday and Monday.

-AAP