BUTTE COUNTY (CBS13/AP) – As predicted, gusty winds moved into parts of Northern California as another power shutoff was rolled out to prevent sparking wires from igniting new wildfires.

Pacific Gas & Electric’s online map of public safety power shutoffs showed outages in the northern Sacramento Valley, northern Sierra Nevada foothills and a few elsewhere, affecting more than 32,500 customers in nine counties Thursday morning. The utility began shutoffs Wednesday night and said as many as 37,000 customers in 15 counties could be affected.

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By Thursday evening, PG&E said power had been restored to approximately 74% of affected customers. As of 7:30 p.m., nearly 8,000 customers remained in the dark. They expect to restore power to “essentially all” of the 31,000 customers impacted by the end of Friday.

Fewer customers lost power Wednesday evening, PG&E said, because of changing weather conditions.

The National Weather Service warned of low humidity and gusty winds into Friday. PG&E meteorologists are also monitoring another wind event forecasted for Sunday that has the potential the force a larger-scale PSPS event. The utility plans to send out notifications on Friday to customers who may be impacted by that wind event.

Investigations, meanwhile, cited electrical equipment failure during windy, dry weather as the causes of two Southern California wildfires last year, a fire agency announced Thursday.

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The 1,800-acre (728-hectare) Easy Fire, which threatened the Ronald Reagan Presidential Library and nearby Simi Valley homes, was ignited Oct. 30, 2019, when an insulator attached to a Southern California Edison high-voltage transmission line swung into a steel power pole, the Ventura County Fire Department said in a press release.

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The department also said the nearly 15.6-square-mile (40-square-kilometer) Maria Fire near Santa Paula was ignited Oct. 31, 2019, by failure of a conductor on an electrical distribution line owned by California Resources Corp.

Emails seeking comment were sent to both companies.

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