Some of the first real rain since spring will be drizzling over the Bay starting Wednesday and continuing into Thursday, but Southern California will be getting the brunt of the incoming storm.
A passing shower is possible Wednesday morning or afternoon in SF, with rain likelier to come later on Wednesday night and into Thursday. The National Weather Service says there's a sub-30% chance of a passing thunderstorm at some point, and they forecast very little rain accumulation in San Francisco proper — in the range of one-tenth to one-quarter of an inch.
?️Widespread beneficial rain is expected tonight through Thursday with a low potential for thunderstorms over the Big Sur coast. Slick roadways and minor nuisance flooding are possible, and high rain rates over the burn scars may lead to debris flows. #CAwx https://t.co/G1vIFLw5zI
— NWS Bay Area ? (@NWSBayArea) October 21, 2026
The Big Sur coast will see heavier rain today and tomorrow, while Southern California will get even more.
As the Chronicle weather team reports, much of SoCal is expected to see a drenching on the magnitude of 1.5 inches, and even up to 3 inches on mountain slopes.
This storm is also likely to bring the first snow of the season to the higher elevations of the Sierra, potentially up to eight inches in places.
Per the Chronicle, the rain is expected to taper off around the Bay on Thursday morning.
San Francisco last saw brief showers on September 17, and on August 14, with 0.06 inches falling on June 27.
The effects of this monster El Nino we've all been hearing about are probably still at least a month off, with forecasters saying that November is likely to see about average rainfall.
