Bay Area pounded by heavy rains and high winds; isolated thunderstorms still possible
The Bay Area was soaked by a powerful storm system overnight into Saturday morning, causing flooding and even triggering what is reported to be the first-ever tornado warning in San Francisco, officials said.
While the strongest part of the system with the heaviest rain and strongest winds has passed, isolated severe thunderstorms are possible for parts of the Bay Area through the morning, the National Weather Service said.
The risk of a severe storm is marginal, and the NWS said it will only last through Saturday morning. According to PG&E, the storm conditions caused power outages for thousands of people in the Bay Area.
An outage map shows several areas throughout the region where at least 500 customers are without power.
The @NWSSPC has issued a marginal Risk for Severe Thunderstorms for parts of the Bay Area and Central Coast for possible severe wind gusts this morning. Secure all loose objects outdoors! When thunder roars, go indoors! See a flash, dash inside! #CAwx pic.twitter.com/ecbNJoIa8a
— NWS Bay Area 🌉 (@NWSBayArea) December 14, 2024
After that, isolated shower activity is expected throughout the afternoon, but it will be a lot drier today.
A flood advisory is in effect for part of Petaluma until 1:30 p.m., an there is an ongoing Wind Advisory in the Interior Bay Area and Interior Central Coast effective until Saturday, 10 a.m. Coastal flooding is expected along the San Francisco Bay and San Pablo Bay until Monday, 1 p.m
For Saturday's temperatures, daytime highs will be mostly in the high 50s to low 60s on the coast, mid 50s to low 60s around the bay, and in the mid to high 60s inland. Overnight lows will be mostly in the mid 30s to low 40s.
Drier weather is expected into Sunday, and there is a chance of fog early Sunday morning.
The National Weather Service had forecasted "impactful" rain for Friday evening into Saturday with flooding concerns for the Bay Area. In Livermore, those flooding concerns turned into warnings from police. Livermore police said many of their under-crossings were closed due to substantial flooding and that cars that tried to drive through were getting stuck.
The storm even prompted a tornado warning early Saturday morning.
A Tornado Warning is in effect until 6:20 AM for northern San Mateo County including portions of downtown San Francisco. Take shelter immediately! #CAwx
— NWS Bay Area 🌉 (@NWSBayArea) December 14, 2024
The tornado warning was issued just before 6 a.m. for San Mateo County and downtown San Francisco, and it expired at 6:20 a.m. The Bay Area office of the National Weather Service said warning was "radar indicated" and there was no confirmation of a tornado touching down.