We had a surprising amount of rain yesterday and overnight at my house: 0.7" and then a bit more on the following day. This is quite late in the season for us to get this much rain - 75% of the time May has 0.25" or less rain in the LA area. The rainfall total of 9.21" is normal for LA, which most frequently gets between 8 and 10 inches of rain per year.
If you have established native plants, they ought to do well in your garden this year with even a moderate amount of supplemental watering. If you are establishing native plants, they will still need a bit of extra water to get through the summer. Deep, infrequent, waterings are usually best.