SAN FRANCISCO (AP) — Many of Waymo's self-driving cars blocked streets of San Francisco during a mass power outage Saturday and forced the company to temporarily suspend service, raising questions about the cars' ability to to adapt to real-world driving conditions.
Social media users posted videos of Waymos as they encountered traffic lights that were off. Some cars’ hazard lights blinked and they abruptly stopped in place, failing to cross the intersection. Others stopped in the middle of the intersection, forcing other cars to swerve around them.
The power outage affected 130,000 homes and businesses in San Francisco, nearly one-third of the customers served by Pacific Gas and Electric Co. It was caused by a fire at a power substation, officials said. On Monday, the utility company was still working to restore power to thousands of customers.
Waymo operates hundreds of robotaxis in San Francisco, but it wasn't clear how many cars were on the road at the time of the outage. The company paused service Saturday evening and resumed it Sunday afternoon.
The road-blocking problems that prompted Waymo to suspend its service during the weekend power outages revived concerns that city officials raised about the robotaxis periodically coming to abrupt and inexplicable stops before California regulators approved them as a commercial service in August 2023.
Tyler Cervini, who lives in the Mission District, said he was calling an Uber to bring him to the airport since his train station was not operating due to the outage. At the traffic light outside his apartment, there were five Waymos crowding the intersection, he said.
He got into his Uber right outside where all the Waymos were, but his driver "had to swerve through them to pick me up," Cervini said. “He seemed extremely frustrated by what was going on.”
Waymo said that its vehicles are designed to treat nonfunctioning traffic signals as four-way stops, but the scale of the outage created unusual conditions.
“While the failure of the utility infrastructure was significant, we are committed to ensuring our technology adjusts to traffic flow during such events,” a Waymo spokesperson said. “Throughout the outage, we closely coordinated with San Francisco city officials.”
The company said most active trips were completed before vehicles were safely returned to depots or pulled over.
Philip Koopman, professor emeritus at Carnegie Mellon University and expert on self-driving vehicle safety, said the scale of the traffic disruption was concerning. Autonomous vehicles are generally programmed to come to a stop if they are unsure or confused on what to do and ask for remote assistance, he said.
Koopman said it did not appear to be a software failure in the cars themselves, but an “operational management failure” where the company did not have the capability to deal with so many robotaxis needing assistance at once.
Waymo should have suspended service earlier — as soon as their vehicles started having issues, he said.
“If you have thousands of robotaxis that stop, you have a problem,” he said. “What if this had been an earthquake? You would have thousands of robotaxis blocking the road.”
Waymo, which started as a secret project within Google in 2009, has steadily expanded its operations in San Francisco while also introducing its robotaxis into other California cities such as Los Angeles and San Jose, in addition to other U.S. markets in Texas, Arizona, Florida and Georgia.
In the months leading up to the approval from the state’s Public Utilities Commission, San Francisco's transportation and fire department leaders flagged dozens of reports about robotaxis coming to standstills, blocking traffic.
Besides inconveniencing other drivers trying to get to their destinations, the road-blocking robotaxis were viewed as a possible impediment in life-threatening emergencies when firefighters and police officers were responding to calls for help.
Waymo’s fleet of robotaxis is on pace to complete more than 14 million rides this year, more than tripling from last year, according to the company.
California is considering expanding approval for heavy-duty autonomous trucks and vehicles carrying up to 15 passengers to operate, a move opposed by unions representing truck drivers.
Shane Gusman, director of Teamsters California, called the Waymo disruption “a clear warning that turning our roads and lives over to autonomous vehicles is premature and dangerous.”
“We live in a state where blackouts, wildfires, floods and earthquakes affecting power and roadways are all too common," Gusman said in a statement. “AVs stalled in streets and intersections threaten the safety of AV passengers, and others on the road, and inhibit emergency response when we need it most.”
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Ding reported from Los Angeles.
Cars wait at an intersection with no working traffic lights from power outages, in San Francisco, Saturday, Dec. 20, 2025. (AP Photo/Jeff Chiu)
Pacific Gas & Electric crews walk around the substation building at 8th and Mission streets, in San Francisco, Monday, Dec. 22, 2025, as they work to repair infrastructure that failed and caused massive power outages across the city. (Jessica Christian/San Francisco Chronicle via AP)
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)
Charlotte's surge to at least the play-in tournament and possibly the playoffs in the Eastern Conference has been fueled in large part by the 3-point shot.
And by season's end, it's well within reach that the top two 3-point shooters in the NBA this season — at least in terms of makes — both might be wearing Hornets uniforms.
Charlotte rookie Kon Knueppel leads the NBA with his Hornets-record 261 made 3s so far this season, and LaMelo Ball is currently third in the league with 243 makes from beyond the arc. Between them: the Los Angeles Lakers' Luka Doncic, who is set to miss some time with a hamstring injury.
Knueppel already has the NBA record for 3s made by a rookie as well.
“He definitely needs to celebrate,” Hornets coach Charles Lee said.
If Knueppel and Ball finish 1-2 in the final standings for made 3s, they would become the second set of teammates in NBA history to hold down the top two spots on that list for a full season. The other, as one would likely guess, were the “Splash Brothers” — Golden State's Stephen Curry and Klay Thompson, who finished first and second in the season standings in four consecutive seasons from 2013-14 through 2016-17 (and nearly did it in 2012-13 as well).
Other pairings have come close. Antoine Walker and Paul Pierce were second and third in made 3s for Boston in 2001-02 (behind Ray Allen, the then-future Celtic who was playing for Milwaukee at the time). And in 1992-93, Phoenix's Dan Majerle tied Indiana's Reggie Miller for the made-3s title, with Suns teammate Danny Ainge finishing third.
Here's what we know so far regarding the NBA playoff field for this season.
— Eastern Conference playoff teams: Detroit, Boston, New York, Cleveland are in. At this point, Atlanta and Philadelphia would get the other two guaranteed spots but those are not clinched.
— East play-in teams: Nobody is locked into the play-in yet, but entering Friday, the four teams headed there are Toronto, Charlotte, Orlando and Miami.
— East eliminated teams: Milwaukee, Chicago, Indiana, Brooklyn and Washington.
— Western Conference playoff teams: Oklahoma City, San Antonio, the Los Angeles Lakers, Denver and Houston are in. Minnesota is likely to grab the sixth and final guaranteed spot.
— West play-in teams: Phoenix is probably going to the play-in tournament. Portland, the Los Angeles Clippers and Golden State definitely are.
— West eliminated teams: Memphis, New Orleans, Dallas, Utah and Sacramento.
— Hornets 127, Suns 107: Charlotte clinches no worse than a .500 record.
— Pistons 113, Timberwolves 108: Detroit closing in on East No. 1 seed.
— Thunder 139, Lakers 96: Luka Doncic hurt, Lakers tie 7th-biggest loss in team history.
— Cavaliers 118, Warriors 111: Cleveland on brink of clinching top-4 seed.
— Trail Blazers 118, Pelicans 106: Portland made 20 3s, New Orleans made nine.
— Spurs 118, Clippers 99: Victor Wembanyama sits, Spurs win 11th straight anyway.
— Indiana at Charlotte: A winning record this season is going to get Hornets’ coach Charles Lee some award votes.
— Minnesota at Philadelphia: Massive implications seeding-wise for both teams.
— Atlanta at Brooklyn: Hawks closing in on Southeast Division title, possibly No. 5 seed.
— Chicago at New York: Knicks nearing the 50-win mark yet again.
— Utah at Houston: The Rockets know they can’t afford a slipup in this spot.
— Toronto at Memphis: Raptors need a few wins down the stretch to avoid play-in.
— Boston at Milwaukee: Bucks coach Doc Rivers faces his former team, a day before expected Hall of Fame formal announcement.
— Orlando at Dallas: Magic coach Jamahl Mosley enjoyed a lot of nights when he was on the Mavs’ staff. He desperately needs one of those good nights here.
— New Orleans at Sacramento: A pair of teams building for the future.
— Washington at Miami: Bam Adebayo scored 83 against the Wizards last month. The rematch!
— San Antonio at Denver: Wembanyama vs. Nikola Jokic in potential West playoff pairing.
— Detroit at Philadelphia: Sorry, Detroit. Michigan-Arizona Final Four game tips off during this one.
Friday on NBA TV: Chicago-New York.
Saturday on Prime: San Antonio-Denver.
Saturday on NBA TV: Detroit-Philadelphia.
Oklahoma City (+135) is favored to win the NBA title, according to BetMGM Sportsbook, followed by Boston (+550), San Antonio (+550), Denver (+1100), Cleveland (+1200) and New York (+1600). Detroit, on its way to the No. 1 seed in the East, is +2500.
— April 10: All 30 teams play their 81st games of the season.
— April 12: All 30 teams play their regular season finales.
— April 14, 15 and 17: NBA play-in tournament dates.
— April 18 and 19: NBA playoff series openers.
— May 2, 3 or 4: Conference semifinals begin.
— May 10: NBA draft lottery.
— May 10-17: NBA draft combine.
— May 17 or 19: Eastern Conference finals begin on ESPN and ABC.
— May 18 or 20: Western Conference finals begin on NBC and Peacock.
— June 3: Game 1, NBA Finals on ABC. (Other finals dates: June 5, June 8, June 10, June 13, June 16 and June 19).
The Thunder had 14 different players score in their win over the Lakers on Thursday night. There have been only seven games in NBA history, including playoffs, where a team saw more players score at least one point in the same game.
The Spurs are 27-2 since Feb. 1 — and have picked up only 3 1/2 games on Oklahoma City (23-5) in that span. (By the way, the best record in the East since that date belongs to Atlanta at 20-6.)
AP NBA: https://apnews.com/nba
Denver Nuggets center Nikola Jokić, left, struggles to field a pass as Golden State Warriors forward Draymond Green defends in the second half of an NBA basketball game Sunday, March 29, 2026, in Denver. (AP Photo/David Zalubowski)
Denver Nuggets center Nikola Jokic warms up before an NBA basketball game against the Utah Jazz, Wednesday, April 1, 2026, in Salt Lake City. (AP Photo/Rob Gray)
Denver Nuggets center Nikola Jokic (15) looks for a play against Utah Jazz guard John Konchar (55) during the first half of an NBA basketball game, Wednesday, April 1, 2026, in Salt Lake City. (AP Photo/Rob Gray)
Denver Nuggets center Nikola Jokic (15) holds the ball away from Utah Jazz guard John Konchar during the first half of an NBA basketball game, Wednesday, April 1, 2026, in Salt Lake City. (AP Photo/Rob Gray)
Miami Heat guard Pelle Larsson, left, is fouled by Philadelphia 76ers center Adem Bona, right, during the second half of an NBA basketball game, Monday, March 30, 2026, in Miami. (AP Photo/Lynne Sladky)
Boston Celtics guard Jaylen Brown (7) dunks against the Atlanta Hawks in the second half of an NBA basketball game, Monday, March 30, 2026, in Atlanta. (AP Photo/Mike Stewart)
Toronto Raptors centre Jakob Poeltl (front) is fouled by Orlando Magic centre Goga Bitadze (back left) as Magic forward Paolo Banchero (right) looks on during first half NBA action in Toronto on Sunday, March 29, 2026. (Frank Gunn/The Canadian Press via AP)
Boston Celtics forward Jayson Tatum, right, drives against Charlotte Hornets guard Kon Knueppel during the second half of an NBA basketball game in Charlotte, N.C., Sunday, March 29, 2026. (AP Photo/Nell Redmond)
