(KRON) -- Dry weather conditions and strong winds could heighten the risk of wildfires from starting or spreading, leading Pacific Gas & Electric Co. to announce possible power shutoff across the Bay Area starting Thursday. Red flag warning for Bay Area issued Thursday through Saturday Here's which counties would be affected in the Bay Area, according to PG&E: Alameda Contra Costa Napa Solano Sonoma The shutoffs could affect thousands of customers, but the utility company did not specify exactly how many. Specific addresses, maps, and shutoff details are "typically available two days before shutoff," PG&E said. PG&E told KRON4 they are tracking "strong winds," which meteorologists say can reach up to 70 miles per hour across parts of the utility company's service areas. These winds and dry fuel moisture can contribute to fire weather. According to PG&E, these possible shutoffs will last until Sunday. Around 20 counties around California will be affected in total. The entire list can be accessed here. PG&E emphasized that this forecast is based only on weather conditions and fuel moisture content. "It is not a danger forecast," the utility company said.