YOLO COUNTY — Thousands of Pacific Gas and Electric customers in eight Northern California counties may be impacted by a public safety power shutoff that could start Wednesday evening.

The shutoffs are expected to begin by 6 p.m. Wednesday and could impact more than 4,200 customers. The numbers by county are:

• Butte: 435 customers, 36 Medical Baseline customers in Pulga, Crest, Concow, Yankee Hill and Big Bend
• Colusa: 484 customers, 37 Medical Baseline customers in Stonyford, Lodoga, Bear Valley Road
• Glenn: 349 customers, 18 Medical Baseline customers in Elk Creek
• Lake: 186 customers, 20 Medical Baseline customers
• Napa: 7 customers, 0 Medical Baseline Customers
• Shasta: 1,558 customers, 131 Medical Baseline customers in Igo, Round Mountain, Oak Run and Montgomery Creek
• Tehama: 1,117 customers, 124Medical Baseline customers
• Yolo: 10 non-residential customers northeast of Brooks

Additionally, two tribal communities could also be impacted.

• Grindstone Rancheria: 48 customers, 4 Medical Baseline customers
• Pit River Tribes: 8 customers, 0 Medical Baseline customers

The potential shutoffs are a result of a forecasted dry wind event that will strengthen the risk of wildfires. The weather event should last through the night and into Thursday morning.

PG&E said it has already started sending notifications to those in the affected areas.