Well, Thanksgiving is tomorrow and that's the start of the Christmas season, literally. Many stores are doing big sales on Thursday. I don't plan on doing any of those sales. I don't know what to buy people anymore, anyway. I've heard that many sales are really not that big of a bargain if you know when to buy things. I also don't like the crowds.
There are several "Turkey Trots" around town in the morning. Exercising is good on a day where you eat a lot. There's the San Diego Turkey Trot and Food Run. It's held at Rohr Park in Bonita. Be sure you bring a non-perishable food when you run. You can find out more at www.sdthanksgivingrun.com. Father Joe's, a well known charity and shelter here in town, also holds their own turkey trot and encourage people to "move your feet before you eat". You can find out more about their run at https://my.neighbor.org/sslpage.aspx?pid=411
Many places you might not expect to be closed tomorrow will be. Lake Murray will be closed and there is no parking anywhere except the street. It's also one of busiest days of the year at the lake. Expect to have problems with parking and crowds. Also, since the lake is closed, fishing will not be allowed. Anyone who fishes on that day is poaching. Please save your fishing for the days the lake is actually open. You are free to walk and picnic at the lake. Be aware that you will probably have to walk a long way to get to any picnic areas.
If you want to do some bird watching, or bike riding, the usual bike paths and hotspots will be open along the South Bay and San Diego River.