PG&E announced late Sunday that it was giving its mandated 48 hours advance warning of possible public safety power shutoffs (PSPS) in 16 counties due to dry winds starting on Tuesday night.

The first PSPS event of the fire season looks to be coming this week, months ahead of the typical timeframe for the annual Diablo winds that have downed power lines and led to wildfires in recent years. And while the majority of power customers losing power will be in Butte and Shasta counties, some parts of the Bay Area will be impacted as well.

"Forecasted Offshore Dry Winds Mean PG&E Might Need to Proactively Turn Off Power for Safety in Small Portions of 16 Counties on Tuesday Night," the company said in a Facebook post, listing Napa and Sonoma counties among the 16.

"Given this wind event and current conditions including extreme to exceptional drought and extremely dry vegetation, PG&E has begun sending 48-hour advance notifications to customers in targeted areas where PG&E may need to proactively turn power off for safety to reduce the risk of wildfire from energized power lines," PG&E said in a separate Sunday release.

The shutoffs are expected to impact just over 1,800 customers in Napa County, and just over 100 in Sonoma County. But upwards of 27,000 customers will be impacted between Shasta and Butte counties.

A Red Flag warning is expected to be issued as well beginning at 3 p.m. today, just as high heat will be impacting many inland areas. The last Red Flag warning came one month ago, on July 17, amid a threat of possible thunderstorms.

In recent weeks, the Berkeley Fire Department issued its own advance warning framework for city residents, specifically explaining that residents of the Berkeley Hills will be asked to preemptively evacuate during specific periods of extreme fire risk. Those periods include times when low humidity combines with sustained off-shore winds over 30 miles per hour.

PG&E has said that such power shutoffs are a last resort to prevent fires, but a federal judge earlier this year suggested that PG&E needed to do more in its safety efforts. Despite these PSPS events going on for several years, the 2020 Zogg Fire in Shasta County appears to have been caused by live PG&E lines amid high wind, and both the Kincade Fire in 2019 and the massive, ongoing Dixie Fire appear to have been caused by PG&E equipment as well.

In its release, PG&E says that a new criterion has been added to the list for triggering a PSPS. "This year, our decision-making process is evolving to also account for the presence of trees tall enough to strike power lines when determining if a PSPS event is necessary," the company says.

Photo: American Public Power Association