To the list of people suing Pacific Gas and Electric Co. over last month’s Wine Country fires, add the former top official of PG&E’s hometown — former San Francisco Mayor Frank Jordan.

Jordan and his wife, Wendy Paskin-Jordan, will join a suit blaming PG&E for sparking the fires, law firm Cotchett, Pitre & McCarthy reported Monday. Jordan is expected to appear at a news conference Tuesday at the firm’s Burlingame office.

Jordan and his wife owned a weekend home on Mark West Springs Road in Santa Rosa. They fled the night of Oct. 8 after seeing flames in the distance and warning their neighbors.

“When I looked up, the flames were 50 or 60 feet high coming over the hills,” Jordan told The Chronicle last month. “And they were coming our way.”

A Santa Rosa couple who lost their home in the Tubbs Fire sued PG&E Co. in San Francisco Superior Court today, claiming the fire was caused by alleged negligence by the utility in maintaining electric lines and pruning trees and vegetation.

The house was destroyed. The couple has been living at their home in San Francisco’s Pacific Heights neighborhood since then. Jordan served as mayor from 1992 to 1996.

As of last week, more than 120 plaintiffs had filed 15 separate suits against PG&E over the fires, according to an estimate the utility included in a legal filing last week.

Investigators with the California Department of Forestry and Fire Protection, or Cal Fire, have not yet determined a cause for any of the fires, which together burned 210,000 acres, destroyed 8,900 structures and killed at least 43 people. And PG&E last week suggested that the most destructive of the blazes — the Tubbs Fire, which leveled the Jordan home — may have been started by power lines owned and installed by someone else.

Cotchett, Pitre & McCarthy has hired its own investigators and plans to file a new suit Tuesday, working with law firms Dreyer Babich Buccola Wood Campora; Panish Shea & Boyle; Walkup, Melodia, Kelly & Schoenberger; and Abbey, Weitzenberg, Warren & Emery.

“The nearly 50-page complaint being filed contains the most comprehensive and exhaustive assessment of multiple failures by PG&E that led or contributed to some of the most destructive and deadly wildfires California has ever seen,” attorney Frank Pitre said in a news release Monday.

PG&E spokesman Keith Stephens noted in response that Cal Fire’s official investigation remains underway, and PG&E is cooperating with it.
“Our primary focus has been — and continues to be — the safety and well-being of the customers and communities that have been affected by these wildfires,” he said, in an email.

David R. Baker is a San Francisco Chronicle staff writer. Email: Twitter: @DavidBakerSF