May 4, 2026 — Over the past several months, an intense marine heat wave has developed in the Pacific from Washington to Baja Mexico, with a particularly extreme hot spot between the Bay Area and San Diego. Ocean temperatures have spiked to as much as 7 degrees hotter than average, with many places breaking records for this time of year.
The heatwave off the California coast is already causing starving birds to wash ashore and could increase the risk of thunderstorms and dry lightning that could worsen the wildfire season, scientists say.
Researchers at the Scripps Institution of Oceanography at UC San Diego have recorded 38 days since Jan. 1 when the surface temperature off their La Jolla pier in San Diego broke records going as far back as 1916. On March 20, the ocean there reached 71 degrees, the hottest ever recorded in March and a level normally seen in August.
“It’s extreme,” said Melissa Carter, a Scripps oceanographer. “We have had heat waves in the past. But this is a record event for the duration and the intensity.”
Farther north, ocean temperatures also have broken records on 31 days this year off Newport Beach; 38 off Santa Barbara; 22 at Pacific Grove near Monterey; 9 days at the Farallon Islands off San Francisco; and 14 at Trinidad in Humboldt County.