The Gallatin is a solid producer right now. The entire river is productive at the moment. In the canyon stretches smaller nymph patterns on 5x flourcarbon are very good. Most of the dry fly action is still based on terrestrials and a sparse trico hatch but the surface action has been spotty at best - as we move later into the fall that should improve with some baetis action. On the lower river try dead drifting some streamers or wooly buggers trailed with a baetis emerger. Trout are transitioning out of the faster water and riffles and moving into some slicks. The lower river is still marginal but should improve as flows increase with reduced irrigation.
The Month Ahead:
The Gallatin will continue to fish well during the fall. The lower river will improve as temperatures continue to drop and flows bounce back a bit with reduced irrigation in the lower valley. Baetis mayflies will begin to make a daily appearance although the hatch is very sparse on sunny days. If you catch the river on a cloudy day with some light rain it can produce outstanding hatches and great surface action. The Gallatin is not a great fall run brown river but it can still produce some decent browns in October, especially on the lower water. Rainbows will also follow browns into spawning riffles and you can have good success fishing egg patterns in some side channels below these areas.
Long Term Fishing Forecast:
The Gallatin will continue to fish well during the fall and early winter. The water near Big Sky has some springs that keep ice shelves at bay and that water is productive on smaller nymph rigs well into the winter. As water temps drop fish will move out of the fast water and back into