At this point they expect flooding and a lot of trees down and power outages by Sunday from the rain and winds

Between Thursday (it's now just after midnight) into Thursday I see a little rain outside on our deck in the back yard. However, the weather people said by Saturday or Sunday it should be flooding and trees coming down with power outages many places. So, people are girding themselves around the San Francisco area preparing for that in one way or another. 

California is different than most places in that we can get up to 15 or more inches of rain in a couple of days. We already got at least 4 inches of rain most places this week already. So, by Saturday and Sunday a little wind is going to start uprooting trees from all the wet all along the coast near San Francisco. The winds really come off the ocean sometimes at 100 miles per hour because there are no trees or mountains in the ocean to slow the winds down. But, so far, the rain hasn't hit hard and likely won't until Friday or Saturday.