A record-breaking heat wave will scorch Southern California this week, raising temperatures up to 35 degrees above normal for March and heightening concerns about heat-related illness and deaths.
After a brief reprieve from sweltering temperatures over the weekend, dangerous heat once again descended on the region Monday, bringing a host of warnings from the National Weather Service. Temperatures are expected to peak Tuesday through Friday, with the mercury rising into the 80s along the coast and into the 90s and past the 100-degree mark inland, likely shattering records.
“It looks like it’s going to be a historic heat wave,” said Robbie Monroe, a meteorologist with the National Weather Service in Oxnard. “This could be the hottest March heat wave we’ve ever had, depending on how it plays out.”
The weather service issued a heat advisory starting at 10 a.m. Monday and lasting through 10 a.m. Tuesday. By Tuesday morning, the advisory will become an extreme heat warning that will remain until 8 p.m. Friday for much of the Los Angeles County area including Woodland Hills, East Los Angeles, Thousand Oaks, Beverly Hills, Glendale and Westlake Village. The weather service warns of dangerously hot conditions with temperatures between 96 and 104 degrees.
Adding to the heat stress, it’s expected to stay relatively warm overnight, with lows in the mid-60s to mid-70s, Monroe said.
“In fact, it’ll be so warm overnight that they’ll be close to our average high temperatures for March for many areas,” he said. “The warmest foothills might not even dip below 80 degrees at times, which would be near, if not above, normal high temperatures for some of those areas.”
The lingering overnight heat significantly increases the risk of heat illness because the body doesn’t have a chance to cool down, leading to cumulative strain, heat exhaustion and even heatstroke, which can be deadly, experts say.
Heat-related deaths are on the rise in California as climate change has led to more prolonged and severe episodes of extreme heat. A Times analysis in 2024 showed that heat has caused or contributed to the deaths of more than 21,500 Americans since 1999.
Unhoused individuals, people who work outdoors, older adults, infants, children, pregnant people and those with chronic health conditions or disabilities are at a greater risk of heat-related health impacts, according to the California Department of Public Health.
However, heat-related deaths are preventable.
Angelenos can take advantage of cooling centers at public libraries and community centers across the county. The weather service also urges that people stock up on water and other hydrating liquids for the week, avoid going outside or working outdoors between 10 a.m. and 5 p.m. and check in on neighbors and loved ones who might be at risk of heat-related illness.
Temperatures by Friday are expected to reach 91 degrees in Santa Barbara, 98 degrees in downtown Los Angeles, 97 degrees in Long Beach, 100 degrees in Canoga Park and Santa Clarita and 103 degrees in Covina. In Orange County and the Inland Empire, temperatures will soar to 99 degrees in Anaheim, 82 degrees in San Clemente, 105 degrees in San Bernardino, 102 degrees in Riverside and 103 degrees in Hemet by Friday, according to the weather service.
“This is effectively a full-on summer heatwave in March,” Daniel Swain, a climate scientist, wrote on X.
