More than 800,000 Californians are without power Wednesday morning as the state’s largest electric company tries to avoid sparking wildfires.

After weeks of warnings, Pacific Gas and Electric cut the power to most of their customers in northern California.

The region is under an extremely high risk of fast-moving, catastrophic wildfires with a combination of dry conditions and some of the strongest wind gusts they have seen since 2017.

The winds are expected to last until Friday.

PG&E says it is doing whatever it can to avoid starting a blaze.

Last November the company is believed to have started one of the deadliest wildfires in U.S. history.

There is no word on when the power will be turned back on.