PG&E has warned 386 customers in rural Alameda County that their electricity could be shut off beginning Friday afternoon as hot, dry and gusty weather raises the risk of wildfire-sparking power lines. The potential Public Safety Power Shutoffs would affect an area south of Altamont Pass that includes part of Livermore and unincorporated Alameda County. If power is cut, it may not be restored until noon Sunday, the utility said. A handful of customers in rural Napa County could also lose service, though no number was specified. Temperatures in Livermore are forecast to rise above 80 degrees. PG&E says it may shut off electricity to reduce the chance that wind will cause energized lines to move and ignite a fire. Similar shutoff warnings are in place across about 13 California counties. The planned interruptions are precautionary, but they could leave residents without power through much of the weekend. Customers in affected areas should prepare for a possible outage and check PG&E updates for changes to the warning or restoration timeline.