BAY AREA, CA — PG&E is warning Bay Area residents to prepare for possible power shutoffs as strong winds and increasingly dry conditions threaten to elevate wildfire risk across Sonoma and other counties beginning Wednesday.
The utility has identified Wednesday, Thursday, and Friday as potential public safety power shutoff days as weather conditions shift toward a pattern favorable for rapid fire growth.
In the Bay Area, portions of Sonoma and Napa counties could be affected first. PG&E also listed Colusa, Glenn, Lake, Sutter, Tehama, and Yolo counties as areas facing an elevated risk of shutoffs. No outages are as yet anticipated Monday, Tuesday, or Saturday.
However, PG&E also cautioned that because of the connected nature of the electrical grid, customers outside the highest-risk areas could still be affected by a shutoff event.
PG&E activated its Emergency Operations Center ahead of the anticipated offshore wind event.
The National Weather Service expects fire concerns to increase Wednesday across the North Bay's interior mountains as gusty northerly winds combine with low humidity and increasingly dry vegetation.
Forecasters expect sustained winds of 15 to 25 mph, with gusts reaching 30 to 45 mph across the Sacramento Valley, Delta region, and nearby higher terrain.
Wind speeds could climb even higher on prominent North Bay peaks, including Mount St. Helena, where gusts may reach 50 to 60 mph.
Low humidity levels during the day Wednesday, followed by poor overnight moisture recovery into Thursday, will further increase fire concerns, according to a PG&E alert based on National Weather Service forecasts.
Offshore winds are expected to remain locally breezy through Thursday morning before easing later in the day.
PG&E's seven-day forecast shows elevated shutoff risk in Sonoma, Napa, Lake, Colusa, Glenn, Tehama, Yolo, and Sutter counties on Wednesday and Thursday.
The utility emphasized that shutoff decisions are made at a much smaller geographic level than county boundaries, meaning only portions of a county may ultimately lose power. But the statement did not include details about which areas within the counties might be affected.
The utility said shutoff decisions are based on weather forecasts, expected wind damage, and moisture levels in both live and dead vegetation. Officials stressed that the forecast is not a fire danger rating, but rather an assessment of conditions that could increase wildfire risk near electrical equipment.
Looking beyond the midweek wind event, forecasters expect temperatures to climb sharply as high pressure builds across Northern California. Triple-digit heat is possible later this week and into the weekend in interior valleys and some inland coastal communities.
Fire officials are also monitoring vegetation conditions closely. While some higher-elevation plants have retained moisture from recent weather patterns, lower-elevation species such as chamise and sagebrush are drying out and becoming increasingly flammable. At the same time, abundant grass growth across lower elevations continues to cure, creating additional wildfire fuel.
HWY-128 was shut down between Napa and Yolo counties this afternoon as firefighters battled a vegetation fire, according to CAL FIRE.
A Fire Weather Watch has been issued for portions of the Sacramento Valley from Wednesday morning through Thursday afternoon because of the combination of conditions.
Residents can check PG&E's outage alerts and prepare emergency supplies, backup charging options, and evacuation plans before conditions deteriorate later this week.
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