Flows have dropped in the Box to around 600 cfs. While this is low for this year it is at a good water level for the fishing. If you are fishing Box Canyon your best bet is to have a nymph tied on, whether you are dry dropping or nymphing. While fishing I would be focusing on the deep runs and the pocket water where you expect fish to sit. Play around try and find the bottom and when you do judge your depth and keep it there. Some good patterns to use would be a size 12 Black Rubberlegs or a Duracell Nymph. If you want to throw a dry dropper, I recommend a size 10 Raspberry Chubby. If you do want to switch things up especially on these rainy overcast days try throwing a Sparkle Minnow or a Copper Zonker pattern.