Western Montana Fly Fishing Report
Blackfoot Access Update
The construction-related Blackfoot floating closure below Weigh Station Fishing Access Site has been lifted.
Montana FWP announced the closure was lifted October 2 after the construction-related hazard was removed. The lower Blackfoot through the Milltown area is once again available for floating, subject to normal access conditions and any new hazards that develop.
Current Restrictions and Regulations
Montana FWP currently lists no emergency fishing or hoot-owl restrictions on the Bitterroot, Blackfoot, Clark Fork, Rock Creek, or West Fork Bitterroot.
- Blackfoot: The temporary construction-related floating closure has been lifted.
- Rock Creek: Fishing from boats or vessels remains prohibited July 1 through November 30. Wade fishing only.
- Bitterroot, Clark Fork, and West Fork: No current emergency angling restrictions affecting our normal fishing areas.
- Reminder: Check Montana FWP before launching because emergency conditions can change.
Regional River Conditions Overview
The rivers remain low, clear, and cold, but several gauges have gained a little water compared with last week. The upper Bitterroot, Bell Crossing, Blackfoot, Clark Fork, and Rock Creek have all improved modestly. The West Fork remains extremely low.
The best fishing is now firmly a midday event. Water temperatures on several rivers are sitting in the low-to-mid 40s early in the day, and trout are generally conserving energy until the water warms. There is little benefit to being on the water at sunrise.
Sunday through Wednesday should offer relatively comfortable fall conditions. Thursday brings increasing clouds and a chance of rain, followed by a colder, wetter Friday. Those two days may produce the strongest BWO activity and streamer fishing of the week.
October Caddis remain useful, especially during the warmer first half of the week, but they are no longer the entire program. Small mayflies, midges, nymphs, and streamers should receive increasing attention as the week progresses.
Bitterroot River
Conditions
The Bitterroot remains clear and technical, but flows have improved slightly on the upper and middle river. Latest verified readings are approximately 233 CFS near Darby, 426 CFS at Bell Crossing, and roughly 840 CFS near Missoula.
The lower river still provides the most forgiving water, while the upper river remains considerably shallower and more technical. Expect clear water, selective fish, and better activity once the river warms late morning.
Where to Fish
- Riffle transitions into deeper green water
- Foam lines and inside seams
- Tailouts and slicks when fish are rising
- Deep buckets and soft shelves
- Wood and shaded structure
- Side channels with adequate depth and current
How to Fish It
- Give the river time to warm before expecting consistent surface feeding
- Nymph deeper seams early with Frenchies, Perdigons, Pheasant Tails, and BWO nymphs
- Watch for BWOs and Mahogany Duns from late morning through afternoon
- Fish October Caddis adults or pupa through broken water during warmer afternoons
- Use longer leaders and a single dry when fish become selective
- Carry midge patterns for slow flats and tailouts
- Streamer fish banks, drop-offs, wood, and deeper buckets when clouds or wind develop
Top Patterns
- BWO dry / emerger, size 18–22
- Mahogany Dun, size 14–16
- October Caddis adult or pupa, size 8–12
- Parachute Adams / Purple Haze, size 16–20
- Frenchie, size 14–18
- Perdigon / Pheasant Tail, size 16–20
- Zebra Midge, size 18–22
- Olive or black sculpin / Sparkle Minnow
Blackfoot River
Conditions
The Blackfoot near Bonner is approximately 593 CFS and about 44 degrees early this morning. The river remains clear and relatively low, but the flow is stable and fish have good holding water around deeper buckets, boulder seams, riffle drops, and softer edges.
The lower-river construction closure has been lifted, which restores more normal float planning through the Milltown reach.
Where to Fish
- Deep boulder pockets
- Riffle transitions
- Inside bends
- Deep willow-lined banks
- Soft shelves below heavy current
- Foam lines during mayfly activity
How to Fish It
- Fish slowly and deeper during the cold morning hours
- Use Pat's Rubber Legs or a Zirdle followed by a smaller mayfly nymph
- Watch for BWOs when clouds move in
- Fish October Caddis during warmer afternoon periods
- Use small mayfly and midge patterns in softer seams
- Streamer fish boulder edges, buckets, and deep banks
- Slow the retrieve as water temperatures drop
Top Patterns
- BWO, size 18–22
- October Caddis, size 8–12
- Mahogany Dun, size 14–16
- Pat's Rubber Legs / Zirdle, size 8–12
- Frenchie / Duracell, size 14–18
- Perdigon, size 16–20
- Sparkle Minnow, Sculpzilla, Thin Mint, or Woolly Bugger
Clark Fork River
Conditions
The Clark Fork has received a useful bump and remains the best big-water option in the region. Latest verified readings are around 1,530 CFS above Missoula and approximately 2,340 CFS below Missoula. Water above Missoula was around 44 degrees overnight.
That additional volume gives trout more usable holding water than most of the smaller rivers. Patient anglers should continue finding fish in riffle edges, foam lines, inside seams, current tongues, and slower tailouts.
Where to Fish
- Slow foam lines
- Riffle edges
- Inside bends
- Current tongues
- Tailouts and slicks
- Side-channel seams
- Deep green lanes and soft buckets
How to Fish It
- Watch the water before casting when fish are rising
- Target BWOs with long leaders and delicate presentations
- Carry Mahogany Duns for midday surface activity
- Fish October Caddis through riffles during warmer periods
- Nymph Pheasant Tails, Frenchies, Perdigons, caddis pupa, and midges through deeper seams
- Streamer fish banks, shelves, and structure during cloudy or windy weather
Top Patterns
- BWO Comparadun / emerger, size 18–22
- Mahogany Dun, size 14–16
- October Caddis, size 8–12
- Frenchie / Perdigon, size 14–20
- Pheasant Tail, size 16–20
- Zebra Midge, size 18–22
- Sparkle Minnow, Peanut Envy, Kreelex, or Mini Dungeon
Rock Creek
Conditions
Rock Creek near Clinton is around 265 CFS and roughly 43 degrees. That is a small improvement in flow compared with last week, but the creek remains extremely clear and technical.
Rock Creek continues to be an excellent wade-fishing option for anglers who are willing to slow down. At these temperatures, fish will increasingly favor deeper pools, boulder seams, plunge pools, and soft edges rather than faster summer water.
Where to Fish
- Deep boulder pockets
- Plunge pools
- Riffle drops
- Soft seams
- Undercut banks
- Tailouts during mayfly activity
How to Fish It
- Fish slower and deeper during cold mornings
- Use Frenchies, Perdigons, Pheasant Tails, and Zebra Midges
- Watch for BWOs in slower seams and tailouts
- Carry Mahogany Duns and October Caddis for warmer afternoons
- Use smaller streamers rather than oversized articulated patterns
- Move slowly and make the first cast count
- Remember that fishing from boats or vessels remains closed through November 30
Top Patterns
- BWO dry / emerger, size 18–22
- Mahogany Dun, size 14–16
- October Caddis, size 8–12
- Frenchie / Perdigon, size 14–20
- Pheasant Tail, size 16–20
- Zebra Midge, size 18–22
- Thin Mint, Woolly Bugger, or small olive sculpin
West Fork of the Bitterroot
Conditions
The West Fork near Conner is approximately 80 CFS. It remains extremely low and should be considered highly technical water rather than a general alternative to the mainstem.
Fish are concentrated into the deepest available pools, pockets, and runs. Clear water and limited depth mean poor approaches will shut down productive water quickly.
Where to Fish
- Deepest available pools
- Wood and boulder pockets
- Protected tailouts
- Deeper riffle edges
- Shaded water with adequate depth
How to Fish It
- Use long leaders and 5X–6X tippet
- Stay out of productive water whenever possible
- Fish small BWOs and midges in softer water
- Use Perdigons and Pheasant Tails through deeper pockets
- Make one clean presentation before moving closer
- Consider the mainstem Bitterroot if you want more forgiving fishing
Top Patterns
- BWO, size 18–22
- Mahogany Dun, size 14–16
- Zebra Midge, size 18–22
- Perdigon, size 16–20
- Pheasant Tail, size 16–20
- Small October Caddis, size 10–12
- Small olive streamer
Planning Note
Sunday: Mostly cloudy early, clearing later, with temperatures around the low 60s. Start late. Nymphs, Mahoganies, BWOs, and streamers should cover most situations.
Monday: One of the warmer days of the week, reaching the upper 60s. October Caddis and even an occasional ant or beetle may get a final meaningful afternoon window.
Tuesday and Wednesday: Comfortable fall weather in the low-to-mid 60s. Expect a balanced nymph, Mahogany Dun, BWO, October Caddis, and streamer program.
Thursday: Increasing clouds with rain and possible thunderstorms developing. This could become one of the best BWO and streamer days of the week.
Friday: Rain likely and much cooler, with a high around 50. This is classic late-fall BWO, nymph, and streamer weather. Dress appropriately and fish through the middle of the day.
Saturday: Cold morning near 30 degrees and a high only around the upper 40s. Start late and focus on deeper water, midges, BWOs, nymphs, and slow streamers.
Overall strategy: Late starts are mandatory now. Fish deeper water while it is cold, watch for mayfly activity around midday, and give streamers more time whenever cloud cover, wind, or rain develops.
River Flow Snapshot – October 18, 2026
Values below are the freshest verified readings available when this report was prepared. The lower Bitterroot and Blackfoot readings were updated early October 18; most other gauges reflect the latest October 17 observations. USGS data are provisional.
| River | Section | Gauge | Latest Verified Flow | Status |
|---|---|---|---|---|
| Bitterroot | Upper | Near Darby (12344000) | 233 CFS | Low / Clear / Technical |
| Bitterroot | Middle | Bell Crossing nr Victor (12350250) | 426 CFS | Low / Slightly Improved |
| Bitterroot | Lower | Near Missoula (12352500) | 840 CFS | Best Bitterroot Volume / Stable |
| Blackfoot | Lower | Near Bonner (12340000) | 593 CFS | Stable / 44°F / Float Closure Lifted |
| Clark Fork | Upper | Above Missoula (12340500) | 1,530 CFS | Improved / Best Big-Water Option |
| Clark Fork | Lower | Below Missoula (12353000) | 2,340 CFS | Solid Fall Volume |
| Rock Creek | Lower | Near Clinton (12334510) | 265 CFS | Low / Clear / 43°F |
| West Fork Bitterroot | Lower | Near Conner (12342500) | 80 CFS | Extremely Low / Highly Technical |
The Clark Fork and lower Bitterroot provide the most forgiving volume this week. Rock Creek has improved slightly but remains technical, while the West Fork continues to be the lowest and most demanding option in the drainage.
Fly Box of the Week
Dry Flies
- BWO, size 18–22
- Mahogany Dun, size 14–16
- October Caddis, size 8–12
- Parachute Adams, size 16–20
- Purple Haze, size 16–20
- Griffith's Gnat, size 18–22
- Small ant / beetle, size 14–18
Nymphs
- Frenchie, size 14–18
- Perdigon, size 16–20
- Pheasant Tail, size 16–20
- Duracell, size 14–18
- BWO nymph, size 18–22
- Zebra Midge, size 18–22
- October Caddis pupa, size 8–12
Streamers
- Sparkle Minnow
- Sculpzilla
- Thin Mint
- Mini Dungeon
- Peanut Envy
- Woolly Bugger
- Small olive / black sculpin
Hatch and Fly Chart – Late October Edition
| Hatch / Insect | Activity | Best Time | Recommended Fly | Size |
|---|---|---|---|---|
| BWOs | Primary late-October mayfly, especially during clouds and rain | Late morning–afternoon | Dry, emerger, cripple, or nymph | 18–22 |
| Mahogany Duns | Still an important midday fall hatch | Late morning–afternoon | Mahogany dry, cripple, or emerger | 14–16 |
| October Caddis | Still active but becoming less consistent | Warm afternoons | Adult or pupa | 8–12 |
| Midges | Increasingly important as water cools | Late morning–afternoon | Griffith's Gnat, Zebra Midge, larva or pupa | 18–24 |
| Hecubas | Fading but still possible | Midday | Hecuba / Brindlechute | 10–12 |
| Terrestrials | Low-percentage secondary option | Warm sunny afternoons | Ant or beetle | 14–18 |
BWOs and midges deserve more space in the box every week now. October Caddis are still relevant, particularly Monday through Wednesday, but the colder Thursday-through-Saturday pattern should favor small mayflies, subsurface fishing, and streamers.
Gear Picks of the Week
Long Leaders
Low, clear water is exposing poor presentations. Longer leaders help considerably when targeting selective fish in tailouts, slicks, and foam lines.
4X–6X Tippet
Fine tippet is now standard equipment rather than a special circumstance. Carry enough 5X and 6X for technical dry-fly fishing.
Warm, Waterproof Layers
Thursday and Friday could provide some of the best fishing of the week precisely because the weather is less pleasant. Staying dry enough to remain on the river matters.
Strategy and Expectations This Week
The middle and lower Bitterroot remain the best overall local recommendation. The lower river provides more forgiving volume, while the fall hatch mix remains excellent.
The Clark Fork is arguably the most interesting river this week. More water combined with Thursday and Friday's cloudy, wet conditions could produce the best BWO dry-fly opportunity of the week.
The Blackfoot is once again fully usable from a float-planning standpoint. Focus on deep buckets, nymphs, October Caddis, and streamers.
Rock Creek remains excellent technical wade water. A slight increase in flow helps, but this is still a stealth-and-precision fishery.
The West Fork remains extremely low. Recommend the mainstem Bitterroot to most anglers unless they specifically want difficult small-water fishing.
