Some heavy storms have caused the river to do "its" muddy thing with plugs of chalky water being pretty common. The best bet is to head up the canyon until you find some clearing water and focus on nymphing with small stonefly nymphs, followed by a Lightning Bug or Perdigon variations. There are Spruce Moths still out, but the breezy and cooler weather headed our way will likely keep these in the trees more so than on the water.
There should be clear water stretches here and there, in the meantime focus your efforts up in the Yellowstone Park sections of the river and fish them with large attractor dries such as Para- Wulff in purple or Hopper/Dropper rigs.
Purple Psycho Prince
Black Pat's Rubberleg
Tan Fat Head Moth
Read our "Gallatin River Fishing Guide" to learn more about fly fishing in Montana on the Gallatin River. It is a great resource for anglers fishing near Bozeman Montana and details the various river stretches and seasonal hatches with tips from our Bozeman fly fishing guides.