Snake River
Continuing warm, sunny weather in the region (not that unusual for this time of year) is making for some very good, and comfortable fishing on the Snake River.  Blue-winged olives are out just about everyday.  You will also see intermittent emergences of October caddis on just about every reach of river.  Cooler and wetter days are also producing impressive hatches of mahogany duns.  Fishing is most productive in the morning on nymph rigs in riffle and seam tailouts and along banks.  The surface action starts in earnest after noon, with mayfly and caddis imitations producing best in riffles, seams, flats, and confluence lines.  There can also be acceptable results on larger attractors in the same water and along banks and structure, but even better action can come when these patterns are fished with a dropper – two to three feet should suffice.
Effective dry flies  – Will’s Winged Chernobyls, Circus Peanuts, Grape Apes, Stimulators, Tent-Wing Caddis, Elk Hair Caddis, Goddard Caddis, Sparkle Caddis Duns, Parachute Extended Body BWOs, PMDs, and Mahogany Duns, Comparaduns, Parachute Adams, Parachute Hares Ears, Booty’s PMD, BWO, and Mahogany Emergers, Quigley Cripples, Film Critics, and Pheasant Tail Emergers.
Effective nymphs – Pat’s Rubber Legs, BH Flashback Hares Ear Nymphs, Prince Nymphs, Zug Bugs, Rainbow Warriors, Lightening Bugs, Copper Johns in red or olive, Flashback Pheasant Tails, and Booty’s Deep Stinker Nymph.
Effective streamers – Silvey Sculpins, J.J. Specials, Zoo Cougars, Beldar Buggers, Booty’s Quad Bunny Leech, SRA Bunnies, Cheech’s Leech, Arum’s Lil’ Kim, and Lite Brite Zonkers.

South Fork
Flows are stable and the South Fork comparably more clarity for this time of year compared to mid-autumns over the past few years.  All reaches are fishing well and there is no particular hotspot in terms of holding waters.  Seams, riffles, flats, banks, structure, and eddies are all producing equally well, taking into account variations from day-to-day or reach-to-reach depending on certain weather factors.  As on the Snake, blue-winged olives are dominant, there are intermittent emergences of October caddis, and mahogany duns will be about during periods of cool, wet weather.  Nymphing is still the best way to go throughout the day, but some very good action can develop in riffles, seams, and on flats, in the mid to late afternoon hours with mayfly and caddis imitations.  Larger attractors can produce in certain places, but these are best fished as part of a dry-dropper rig.
Effective dry flies –  Chubby Chernnobyls, Wills Winged Chernobyls, Stimulators, Tent-Wing Caddis, Sparkle Caddis Duns, Elk Hair Caddis, Goddard Caddis, Parachute Extended Body BWOs, PMDs, and Mahogany Duns, Comparaduns, Parachute Adams, Snowshoe Duns, Booty’s PMD, BWO, and Mahogany Emergers, Quigley Cripples, Pheasant Tail Emergers, Q’s Loop Wing Cripples, and Film Critics.
Effective nymphs – Pat’s Rubber Legs, PR Muskrats, Bitch Creek Nymphs, Lightening Bugs, Rainbow Warriors, Flashback Pheasant Tails, Hickey’s Auto Nymph, Copper Johns in red or olive, San Juan Worms, Psycho Mays, and Bruised Mays, and Booty’s Deep Stinker Nymph.
Effective streamers – Galloup’s Sex Dungeons, Booty’s Quad Bunny Leeches, Swimmin’ Jimmies, SRA Bunnies, J.J. Specials,  and  Galloup’s Zoo Cougars.

Yellowstone National Park
The fishing on the Lewis-Snake system continues to be solid with streamers throughout most of the day and dry flies/dry droppers in the afternoon hours.  Fishing on Lewis Lake is best on the flats and drop-offs, particularly at the outlet and at the westerns and northern shores of the lake.  Clouser Minnows, Lite Brite Zonkers, Woolley Buggers, Mohair Leeches, and Kiwi Muddlers have been effective streamers for lake trout and browns in these locales.  The Snake and Lewis Rivers are fishing well with the same streamers and with a variety of mayfly/caddis imitations and larger attractors.  Blue-winged olives and October caddis are the primary emergences on these two streams, and fishing patterns that match these bugs when trout are actively feeding is about as simple as it gets (although mahogany dun and PMD imitations are working well in sizes #14 to #18).  Attractors are also productive, although movement with these patterns is key.