California's largest utility company, Pacific Gas and Electric Co., is cutting power to nearly 800,000 customers across the state as it continues to try to prevent potential wildfires during a dry and windy week.

These mass power shutoffs impact millions of people across more than 50 counties across Northern California, including San Joaquin, Contra Costa, Santa Clara, Yolo and Yuba counties. Hundreds of thousands of students whose classes are canceled because of the outages will also be impacted.

“The safety of our customers and the communities we serve is our most important responsibility, which is why PG&E has decided to turn power off to customers during this widespread, severe wind event," said Michael Lewis, PG&E’s senior vice president of Electric Operations.

RELATED: Watch Live: PG&E begins preventative power shutoffs in Northern California, Bay Area

PG&E is rolling out the outages in three phases, shutting power to upwards to 513,00 customers early Wednesday morning, with more coming later in the afternoon.

It's unclear when PG&E will be turning back on the power

PHASE 1:

The first phase began Wednesday morning at midnight, impacting north of 513,000 customers. Below is a list of counties affected in the first phase.

  • Amador County
  • Butte County
  • Calaveras County
  • Colusa County
  • El Dorado County
  • Glenn County
  • Humboldt County
  • Lake County
  • Marin County
  • Mendocino County
  • Napa County
  • Nevada County
  • Placer County
  • Plumas County
  • Shasta County
  • Sierra County
  • Solano County
  • Sonoma County
  • Tehama County
  • Trinity County
  • Yolo County
  • Yuba County

PHASE 2:

The second phase is expected to roll out Wednesday around noon, impacting more than 234,000 customers. Below is a list of counties affected in the second phase.

  • Alameda County
  • Alpine County
  • Contra Costa County
  • Mariposa County
  • San Joaquin County
  • San Mateo County
  • Santa Clara County

PHASE 3:

The third phase of power shutoffs has still yet to be determined. PG&E said it's considering cutting power to around 42,000 customers in the southern most part of the company's service area.

Stay with ABC10 for the latest updates as more information comes in.

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