Mother's Day Caddis are out (along with a handful of March Browns and small Stoneflies) right now but the flows have come WAY up since a couple of days ago. Expect to see some off-color water conditions and difficult wading at this point. However, there are enough bugs out to bring fish to the surface at different points during the day.
I prefer to fish a Peacock Elk Hair Caddis - in these conditions - and follow it with an unweighed Peacock soft hackle about 2' behind the dry. This can be especially effective when you let that soft hackle swing at the bottom of the drift or when you see fish consistently rising with "splashy" riseforms.
Nymphing with Copper Zonkers, Crayfish patterns, and San Juan Worms - well waited through bank-side buckets is a go to right now as well.
The lower Madison River has diverse wild-trout habitats from Ennis Lake to Three Forks. Beartrap Canyon has raging whitewater through boulder fields and narrow gorges. The river flows through a rugged valley before joining with the Jefferson and Gallatin Rivers. Fish species include Rainbow, Westslope Cutthroat, and Brown Trout. Both novice and advanced anglers can find ample opportunities to fish.
Read the "Lower Madison River Fishing Guide" for a comprehensive introduction to fly fishing in Montana on the lower Madison River from the Bozeman fly fishing guides with Fins and Feathers.