This is from the CDFG newsletter (email). It's so true that fall is a great time to be on the water.
As far as fly fishing in California goes, October has it all. The hardest decision you have to make is where to fish, because the fishing may be good anywhere. Should you head to the high country to take one last shot at the lakes and streams, hit the October caddis hatch on north state rivers, search for big brown trout moving out of lakes to spawn, or target the mythical steelhead on the Klamath and Trinity rivers? These are tough choices, but no matter where you end up, the fishing and scenery are sure to be spectacular. Use CDFW's fishing guide tool to help narrow down your decision.