The San Francisco Blues Festival started 33 years ago and purports to be the oldest ongoing blues festival in the world. It runs today and tomorrow and the weather is perfect. I've been to this several times and must say that it is always a blast. There is lots to see and hear at their web site.
Last Wednesday, Michael Krasney from KQED radio's Forum show interviewed the festival's founder and producer Tom Mazzolini and Angeli Strehli who also performs.