South Australian police plan to conduct patrols in high-risk fire areas this Christmas period, with the state set to sizzle during another hot spell.

Officers involved in Operation Nomad have been told to keep an eye on known firebugs.

Emergency services are also on high alert with predictions fire conditions for Christmas Day will be the worst in 30 years.

High temperatures are expected across South Australia on Friday, with very strong winds sweeping through during the afternoon.

Acting assistant commissioner Scott Duval said public safety was a priority, no matter the day of the year.

"We will be actively patrolling high-risk fire areas," he said.

"We will be visiting depending on the fire-danger ratings people based on their risk on being an arsonist.

"Some of those people maybe visited on Christmas Day depending on how we assess the level risk that's present."

The CFS has issued total fire bans with a danger rating of severe for Christmas Eve in the West Coast, Eastern Eyre Peninsula and Lower South East districts.

Twelve total fire bans have been declared for Christmas Day and include Northwest Pastoral, Northeast Pastoral, West Coast, Eastern Eyre Peninsula, Flinders, Mid North, Mount Lofty Ranges, Yorke Peninsula, Riverland, Murraylands, Upper South East and Lower South East.