A significant power outage cast a shadow over extensive areas of San Francisco on Saturday, leaving approximately 130,000 residences and businesses without electricity and bringing self-driving cars to a halt on the city’s streets.

Pacific Gas and Electric Co. did not immediately disclose the cause of the outage, which affected nearly one-third of its customers in San Francisco. Around 3:15 p.m., fire officials announced via X that part of the disruption stemmed from a fire within a PG&E substation located at 8th and Mission streets.

The blackout initially affected the city’s northern regions, encompassing the Richmond and Presidio neighborhoods as well as areas around Golden Gate Park, before it extended further across the city.

As a result, autonomous vehicles found themselves stranded mid-street, leading to congested traffic in the impacted zones.

The skyline, already obscured by fog, appeared even dimmer as the city grappled with the widespread power failure on Saturday, December 20, 2025. (AP Photo/Jeff Chiu)

The San Francisco Department of Emergency Management said on X there were “significant transit disruptions” happening citywide and urged residents to avoid nonessential travel and treat down traffic signals as four-way stops.

A Waymo vehicle sits idling at an intersection with no operating traffic lights due to power outages, in San Francisco, Saturday, Dec. 20, 2025. (AP Photo/Jeff Chiu)

Waymo temporarily suspended its autonomous ride-hailing service in the wake of the blackout, SFGate reported.

Fox News Digital reached out to Waymo for comment but did not immediately hear back.

A bicyclist drives past headlights from an oncoming vehicle as power outages darken the streets, in San Francisco, Saturday, Dec. 20, 2025. (AP Photo/Jeff Chiu)

PG&E later said that as of 11:30 p.m. Saturday, crews had restored power to about 95,000 customers, with about 35,000 customers remaining without power. The utility company added that crews would continue working through the night.