The storms have soaked the surrounding mountains and the river is currently flowing a little above 1,100 CFS coming into Shasta. The clarity is good, so it's fishable. The October Caddis hatch is done, so try #16-18 red or black midges, small baetis patters and rubberlegs under an indicator. Fish up below Box Canyon/Ney Springs for a more intimate experience.
A good fly box will have various sizes of Parachute Adams from #14 - 18, Dark Stonefly Nymphs in #6-8, Black Midge Nymph Patterns and #12 Bird's Nest, #18 Gordon Prince Nymphs. See suggested fly patterns in the accompanying sidebar for reference.