That cold of water nearly always means it is low and clear too. Especially in our SW WA rivers. Kalama can still have its glacier murke with a temp in the 30s. Of course NF Toutle is always murked. I have never tested NF Lewis to be in the 30s, lowest I have seen is 40) Anyway, I will fish #8 or #10 Spin N Glos on 8lb UG Maxima leaders with #1 hooks. Try both bright and subtle colored Spin N Glos to get them to move to it. Jigs with black in them too. Sometimes drift fishing a stonefly pattern.
Also helps if your'e in "Stealth" mode. No bright clothing, limited wading in the drift, limited splash from the casts, keep the fish ya hook outta the hole for multi-hook-up chances.
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