I think it is a western spotted orb weaver
This looks like an Arabesque orb weaver (Neoscona arabesca).
It’s definitely Neoscona. I’m going with Neoscona Oaxacencis, the Western Spotted because N. arabesca has a brown abdomen. The Western Spotted can be found with a variety of colors for the abdomen. Black seems to be the most common. Both species are in California, so range isn’t a way to tell them apart in this instance.
Thank you for the correction and information, I always appreciate your knowledge!
Thanks! and thank you for helping us with IDs too! The site has never been able to keep up with all of the ID requests since it changed over to Worldwide identifications over 5 years ago. We do as many IDs and questions as we can. Don’t worry too much about messing up. 🙂 The former Moderator was very patient with me though I kept making the same mistakes often.