After luxuriating in the 70s and 80s, the Bay Area will trade warmth for a dose of coastal chill on Wednesday. Temperatures will fall 10 to 15 degrees as onshore winds return — but the bigger story may be what’s not arriving. Forecast models continue to dial back the weekend rain chances that once looked promising.
It’s a classic onshore wind reset, with a not-so-classic culprit.
A weak low-pressure system that had been spinning off the California coast will finally drift toward the Central Coast on Wednesday, dragging a plume of moisture inland. That surge will thicken the marine layer overnight, spreading clouds across the region and bringing a few spotty showers by morning…