Electricity may be shut off to 50,000 Northern California utility customers this week to try to prevent power lines from sparking and igniting new wildfires during a new round of gusty, hot and dry weather.

Pacific Gas & Electric says customers in parts of 19 counties and in two tribal communities were notified Monday of a potential public safety power shutoff as early as Wednesday evening.

PG&E says high-risk conditions may continue through Friday primarily in the northern Sacramento Valley and nearby elevated terrain, the northern Sierra Nevada, the mountains north of San Francisco Bay and Mount Diablo in the East Bay.