LOS ANGELES — California’s endless summer just got hotter.
The National Oceanic and Atmospheric Administration on Thursday confirmed what many people felt and saw: California — along with Idaho, Nevada, Oregon and Utah — recorded its hottest ever June-through-August, known as the meteorological summer. Sixteen other states had among their top-five warmest summers.
Nationwide, the heat during those months tied the 1936 Dust Bowl summer as the hottest on record, with temperatures across the country averaging 2.6 degrees above average.
Conditions have become so dire that the California Independent System Operator, which operates most of the state’s power grid, on Tuesday asked the federal government to declare an “electric reliability emergency” that would allow six natural gas-fired power plants — including facilities in Huntington Beach and Long Beach — to generate power at maximum levels, even if they violate air pollution limits.
It is a scrambling effort by state officials to reduce the risk of rolling blackouts in the face of increased energy demands by adding new electricity supplies, including fossil-fuel resources that contribute to climate change and worsening heat waves — a short-term sacrifice that has nonetheless proved controversial among clean energy groups.
The grid operator was granted a similar request during a heat wave last September, but only for a week. This time, the agency is asking for 60 days — a sign that it expects extreme heat could continue well into the fall.
In the short term, Cal ISO has also extended its Flex Alert for a second day, calling on residents to conserve energy amid above-normal temperatures that lead to high demand in California and the Western U.S.
The Flex Alert asks residents to pre-cool their homes and then raise their thermostats to 78 degrees and avoid using major appliances from 4 to 9 p.m. Thursday, when net demand is typically at its peak. It follows a similar alert for the same hours Wednesday.
But energy is only one of many concerns across the state, where more than a dozen large wildfires are burning. Heat advisories and storm-system warnings are promising to bring challenging conditions to firefighters battling the state’s active blazes and residents living in their path.
In Southern California, the National Weather Service is forecasting very hot and dry conditions, with temperatures in some areas expected to be 5 to 15 degrees warmer than normal through Friday.
The Antelope Valley area could see daytime temperatures as high as 108 degrees, while Los Angeles will climb into the 90s Thursday, Friday and Saturday.
A heat advisory has been issued across the Inland Empire, the Santa Ana Mountains and portions of San Bernardino and Riverside counties through Friday. Residents are advised to seek shade, stay hydrated and avoid any activity that could spark a fire.
Forecasters are also warning of a slight chance of thunderstorms Thursday in the interior areas of Los Angeles, Ventura, Santa Barbara and San Luis Obispo counties, which could bring erratic winds, flash flooding and the “potential for lightning-caused wildfires,” officials said.
“It’s all a concern,” said David Sweet, a meteorologist with the National Weather Service in Oxnard. “If a lightning strike starts a fire, then the gusty winds could push it quickly. And aside from thunderstorm activities, it’s going to be pretty warm and dry. … So with the heat, with any gusty winds — elevated fire danger.”
Record temperatures for Wednesday were registered in Palmdale, Sandberg and Paso Robles on Wednesday, where high reached 106, 95 and 106 degrees, respectively, the National Weather Service said.
But the maximum threat remains in Northern California, where beleaguered fire crews are still battling the 927,000-acre, multicounty Dixie fire and the 217,000-acre Caldor fire burning near South Lake Tahoe.
The National Weather Service said much of the fire zone, including Plumas and Lassen counties and the South Lake Tahoe area, will be hit with gusty winds and the chance of thunderstorms Thursday and Friday, although a cooling trend should bring temperatures down in the days to come.
Dry lightning strikes — which last year spurred a rash of wildfires in the fall — are a possibility. A fire weather watch has been issued across much of Northern California through 11 p.m. Friday.
Rob Clark, a fire behavior analyst on the Caldor fire, warned crews Thursday that the changing weather could pose a threat to firefighters and communities.
Unburned islands within the fire’s perimeter provide “the opportunity for an ignition source, the winds provide the transport and the convection will provide the lift to get those embers over our fire lines,” he said.
Ember-spurred spot fires will be possible up to three-quarters of a mile from the fire lines because of strong wind gusts.
“It is very critical that everybody pays attention to what’s going on around them with this weather system,” he said.
Chief Thom Porter of the California Department of Forestry and Fire Protection this week advised that the fire season is “far from over” and asked residents not to let their guard down as seasonal winds move in and meet ongoing dryness.
“We’re right smack in the middle of wildfire peak season,” he said. “Everybody needs to remain vigilant.”
Porter said the forecast for the coming months could spell even more destruction.
“For September through December,” he said, “the entire state shows drier, more wind events, and large fire activity to continue.”
