The first whispers of relief to California’s prolonged heat wave could arrive Wednesday after temperatures broke all-time high records in parts of the East Bay and the Sacramento Valley over the holiday weekend and shut down some schools in the area Tuesday.
Temperatures across most of the Bay Area are expected to drop by 8 to 15 degrees on Wednesday as a brutal high-pressure system begins to ease. Even so, several more days of dangerously hot weather — including triple-digit highs in eastern Alameda and Contra Costa counties — remain in store, forecasters warned, and heat advisories and warnings remain in effect.
“It’s exceptionally long and exceptionally hot for this time of year,” said Patrick Brown, a climate scientist and visiting scholar at San Jose State University.
Livermore experienced the hottest temperature in the Bay Area’s recorded history on Labor Day at 116 degrees, the National Weather Service confirmed Tuesday, and followed up with just a little less heat and a 113-degree reading.
San Jose hit 109 degrees Tuesday — also breaking its all-time record high temperature set in 2017 (108 degrees).
“We have clear evidence we’re now in a climate where these kinds of severe heat events are more frequent, and the odds of unprecedented events are more likely as a result of the global warming that’s already happening,” noted Noah Diffenbaugh, a climate scientist and professor and senior fellow at Stanford.
Some relief could come Wednesday as a trough of low pressure makes its way down from the Pacific Northwest. Still, after such searing heat, temperatures won’t begin to return to normal for this time of year until the weekend.
“The lid is not on quite as tight, and we can start generating some sea breeze and some fog along the coast Friday and into the weekend,” said Jan Null, a meteorologist with Golden Gate Weather Services. But he warned that inland areas would take longer to cool off: “It’s all in the too-hot-to-do-much category.”
Another day of near-record energy consumption across California is expected on Wednesday, bringing yet more calls for energy conservation amid dire warnings of rolling blackouts. The peak electricity demand was expected to exceed 52,000 megawatts Tuesday, which would set a new record from the previous high of 50,270 megawatts in 2006. A megawatt — 1,000 kilowatts — is roughly enough electricity for the instantaneous demand of 750 homes at once.
In advance of that peak, sporadic power outages were reported across the Bay Area on Tuesday afternoon, affecting thousands of people in Livermore, Danville and portions of Santa Clara County. Pacific Gas & Electric attributed the outages to “weather” but generally did not announce more immediate details.
For the fifth straight day Wednesday, dangerously unhealthy air is forecast for the Bay Area — prompting a Spare the Air Alert due to ground-level ozone levels that could cause difficulty breathing, especially for people in Santa Clara, Alameda and Contra Costa counties.
Across the Bay Area, the sweltering weather forced school athletic directors to move practice times later in the day or flat-out call off events. The East Side Union High School District in San Jose, for example, canceled all outdoor activities scheduled for Tuesday, Evergreen Valley football coach and student advisor Gabe Resendez said in an email.
At Gunderson in San Jose, football coach Jason Harrison said practice times have been moved to no earlier than 5:15 p.m. “Parents have been offering to provide ice-cold waters and Gatorades to the team,” he said.
Elsewhere in the Bay Area, some schools closed or closed early due to power outages — including three schools in the Dublin Unified School District and Diablo Valley College in Pleasant Hill — but many others remained open, and air-conditioned classrooms acted as safe havens for students seeking to avoid the heat. In interior parts of the East Bay, schools kept elementary school children in from recess as if it was a rainy day.
“We’re going the best we can to avoid the weather,” Brentwood Union School District Superintendent Dana Eaton said. “We’re making sure kids get plenty to drink. We do that anyway, but teachers are more aware. We have cold-water stations available, too.”
In other cases, the lack of air conditioning — or problems with existing units — prompted concern by some parents. The San Jose Unified School District posted a letter stating that in the event of an HVAC breakdown or loss, “classroom teachers can temporarily relocate to a space with functioning air conditioning.”
Amy Hibbs, whose child attends Willow Glen High School, said that campus has been dealing with air-conditioning issues since the start of the school year; she said she was concerned that there might not be enough space to relocate students as the district mentioned. She said her child texted her Tuesday morning reporting that they were in a room with a temperature well above the 75-degree threshold stated in the district’s letter.
“It’s like 86 degrees in her classroom. I feel jerked around as a parent,” said Hibbs, adding that the issues were more concerning given the likelihood of additional severe weather going forward. “Climate change is going to generate these extreme heat events or extreme cold events,” she said. “A foundational system needs to be in place, and it needs to be working.”
For people working out in the sun, the weather was almost unbearable.
Helping a crew of workers pave a section of road in Livermore, Shaun Coffey stood on a searing stretch of roadway as steam rose from the asphalt. He said that his crews have been taking 20-minute breaks in an air-conditioned cooling tent. But it only helped so much.
“I’m used to it, but nothing prepares you for heat like this,” Coffey said.
Rick Hurd, Robert Salonga, Scooty Nickerson, and Jane Tyska contributed to this report.