Southern California is about to pull a hard weather U-turn. After a cool, gray, and drizzly start to the week, temperatures are on track to rocket upward by Mother’s Day, with some inland and valley spots likely pushing into the 90s. Monday and Tuesday are expected to stay mostly cloudy, with drizzle along the coast and foothills as a thick marine layer blankets the region. By midweek, warmer, drier air should begin to take over and strengthen through the weekend, potentially reshaping outdoor plans across much of the state.
According to the Los Angeles Times, light rain will focus on the eastern San Gabriel Mountains and parts of the Central Coast, but most locations are expected to see less than a quarter of an inch. The paper reports that the deep, marine-style layer will hold many coastal and basin highs in the 60s on Monday, with example temperatures hovering between about 66 and 70 degrees Fahrenheit. The same coverage notes that a rapid warmup is expected to start around Wednesday and peak on Friday and again on Sunday.
What forecasters are watching
The National Weather Service Los Angeles/Oxnard office says the marine layer will keep early-week temperatures on the cool side along the coast and in the basin, while only producing light, spotty showers over higher terrain. Forecasts from the office show many locations stuck in the 60s before warmer offshore air builds inland later in the week. Forecasters add that the exact timing and strength of that offshore push will dictate which neighborhoods see the biggest temperature jump by Mother’s Day.
Heat arrives for Mother's Day
By Mother’s Day, the warmup should be fully underway. The National Weather Service San Diego office projects that valleys in the San Diego region could climb into the 80s, while the Inland Empire and nearby valleys edge into the lower 90s and the lower deserts top 100 degrees Fahrenheit. The agency has flagged a moderate risk of heat-related illness for heat-sensitive people, pets, and livestock in parts of Southern California.
Forecast products also show roughly a 50 percent chance that downtown Los Angeles hits 90 degrees on Sunday, with nearby valley locations running even hotter. Those probabilities and sample temperature numbers were summarized in a report by the Los Angeles Times, a reminder that Mother’s Day brunch could feel more like mid-summer than mid-spring.
Why it's happening
Federal climate records show this is not happening in a vacuum. The National Centers for Environmental Information reported that March 2026 was the hottest March on record for the continental United States. The Climate Prediction Center outlook also favors above-average temperatures across California through mid-May. That backdrop of near-record warmth, combined with a short-term pattern shift toward warmer, offshore flow, helps explain how the region can flip so quickly from cool and cloudy to summer-like heat.
Heat health and safety
Anyone planning outdoor Mother’s Day activities would be wise to treat this like a warm-season event. Check your local forecast, bring plenty of water, plan for shade, and have a backup indoor option for young children, older adults, and anyone especially sensitive to heat. For official tips on preventing heat-related illness, consult the Centers for Disease Control and Prevention resources on extreme heat.
If you or someone you care for is vulnerable to high temperatures, identify a cool indoor refuge in advance, and do not forget to check on pets and older neighbors during the hottest hours of the day. The calendar may still say spring, but your body could be dealing with something that feels a lot more like July.
