I don’t have an update on the Crooked River but with the last week of never getting out of the 20’s I would guess water temps are cold, fish are a bit lethargic most of the day and there will be some ice along the edges of the rivers.
Is it unfishable? No.
If you wan’t to go, for sure do it. The predominate food sources are Midges which could present themselves as opportunities to you as a larva, pupa and adult, mostly always black now and 20 to 24 hooks. Baetis nymphs, but doubtful to see any significant hatch of mayflies from now until maybe mid to late February. A skinny Nelson, Micro May and 2 Bit Hooker are good ones. Scuds. Frenchie and Perdingons, especially the little micro Perdigons I got from Fulling Mill in Black, Purple and Opal.