PG&E warns it may shut off power amid red flag fire conditions

The area around Mt. Diablo is under a red flag fire warning this weekend amid dry conditions and gusty winds. The area around Mt. Diablo is under a red flag fire warning this weekend amid dry conditions and gusty winds. Photo: Kepka, Mike / The Chronicle 2008 Photo: Kepka, Mike / The Chronicle 2008 Image 1 of / 20 Caption Close PG&E warns it may shut off power amid red flag fire conditions 1 / 20 Back to Gallery

A red flag fire warning was issued for parts of the Bay Area this weekend due to bone-dry conditions and gusty winds.

State firefighters boosted staff levels, and Pacific Gas and Electric Co. warned it may shut off power in some Northern California areas as a safety precaution.

The alert is in effect from late Saturday through Monday morning for the North Bay and East Bay hills, including the Diablo Range, said Roger Gass, a meteorologist with the National Weather Service.

“That’s the result of stronger northeasterly winds,” Gass said. “We are going to have very very dry conditions with relative low humidity.”

Winds will reach up to 30 mph, with gusts up to 50 mph at higher elevations, particularly in Napa County, Gass said.

Temperatures in the North Bay and East Bay hills are going to be warm and above seasonal averages, with highs in the 80s, Gass said.

Due to the fire warning, the California Department of Forestry and Fire Protection is increasing staffing this weekend, according to the agency.

“As we remember the tragic fires that occurred this time last year, they should serve as a reminder for everyone to be prepared for the unexpected. We have increased our staffing, but need the public to remain vigilant,” Chief Ken Pimlott, the CAL FIRE director, said in a statement.

PG&E said it may turn off power overnight Saturday and into Sunday, and possibly Sunday night to Monday morning when winds are expected to pick up.

The counties that could see power outages include Napa, Sonoma, Lake, Sierra, Placer, Nevada, Butte, Yuba, Plumas, Amador, El Dorado and Calaveras, PG&E said Saturday night. Residents of Alameda County also could experience outages, the sheriff’s office said.

The idea behind the practice — not a popular notion among customers — is that a utility line that falls in a windstorm without any power surging through it will not spark fires like those a year ago that caused death and devastation in Wine Country.

Sarah Ravani is a San Francisco Chronicle staff writer. Email: sravani@sfchronicle.com Twitter: @SarRavani