First-ever March heat advisory in NorCal
Northern California is under its first‑ever March heat advisory with daytime highs forecasted between roughly 84°F and 94°F this week — a rare early‑season spike that can affect trails, trailhead parking, and travel comfort Record Temps Lead To NorCal's First Ever March Heat Advisory, Monday afternoon Northern California weather forecast - March 16, 2026. Pack extra water, start hikes early, and expect hotter conditions even at lower elevations.
The National Weather Service issued(weather.gov) a heat advisory that takes effect March 16 and runs through March 20, 2026, covering large swaths of the Bay Area and Central Coast. San Francisco, Oakland and San Jose are among the urban centers that forecasters say could reach or flirt with 90°F this week—temperatures those cities have never recorded in March on their long-term station records.(abc7news.com) Forecasters point to a strong high-pressure ridge building over the Western U.S. as the driver behind the multi-day warm spell, according to national forecast analysis and model guidance.(weather.com) National Weather Service products and the NWS HeatRisk tool show the region shifting from widespread “minor” to pockets of “moderate” heat risk across the advisory period, with valley forecasts calling for notably above-normal daytime highs.(weather.gov) State and institutional safety offices have already responded: Cal/OSHA issued advisories urging employers to implement heat-illness protections, and campus environmental health teams (Stanford, Berkeley) posted precautions for employees during March 16–20.(dir.ca.gov) Local park systems and federal land managers are posting current-conditions alerts and fire-restriction information as well, with East Bay Parks and federal mapping tools highlighting closures and wildfire watchfulness while the dry, warm stretch continues.(ebparks.org)
