Extreme Weather and Heat

The National Weather Service warns that an unusual winter heat wave will push temperatures into the low‑ to mid‑90s across Southern California on Thursday and Friday, March 12–13, 2026, roughly 20 degrees above normal for mid‑March and high enough to raise risks of heat illness. Forecasters say downtown Los Angeles could hit about 93°F and the San Fernando Valley around 95°F as a strong high‑pressure system and lack of cooling onshore winds leave what one meteorologist called the region’s Pacific "air conditioner" effectively shut off. Los Angeles city and county officials are opening cooling centers to help residents without air conditioning, while construction unions say they are increasing access to water, electrolytes, shade and rest breaks for outdoor workers. Residents, including people with disabilities, are adjusting routines to complete errands before peak heat, and experts urge the public to stay hydrated and avoid strenuous outdoor activity during the hottest parts of the day. The hot pattern is expected to expand north early next week, with temperatures possibly topping 90°F around San Francisco and in the Sacramento area, underscoring how climate‑driven extremes are appearing earlier in the season and stressing power, health and outdoor‑labor systems.