Western Montana Fly Fishing Report
Current Restrictions, Closures and Hazards
Montana FWP currently lists no emergency fishing or hoot-owl restrictions on the Bitterroot, Blackfoot, Clark Fork, Rock Creek, or West Fork Bitterroot.
- Blackfoot River: Treat Weigh Station Fishing Access Site as the last takeout. The construction-related floating closure below Weigh Station is still being reported in effect through October 31.
- Rock Creek: Fishing from boats or vessels is prohibited July 1 through November 30. Wade fishing only.
- Clark Fork: Recent reports identify downed trees between Clinton and Turah and between Turah and Sha-Ron. Use caution and get current local information before floating those reaches.
- Weather: Snow and rain Sunday may make upper drainage roads slick or rough, particularly around Rock Creek and the Blackfoot.
Regional River Conditions Overview
Western Montana is now firmly in a cold-water fall pattern. Flows remain low across the region, but water temperatures have dropped into excellent trout territory. The Bitterroot was around 53 degrees midday Friday, the Blackfoot around 49 degrees, the Clark Fork near 50 degrees, and Rock Creek around 48–50 degrees.
The cold front changes the fishing more than the flows do. Sunday and Monday should be slow early. Fish deeper water until the river warms, then watch slow foam lines, tailouts, and soft seams for BWOs and Mahogany Duns.
Tuesday through Saturday should improve progressively as daytime temperatures climb. By Thursday through Saturday, October Caddis should become more relevant again in riffles and broken water. Terrestrials are essentially a secondary option now rather than a core strategy.
Streamer fishing deserves serious attention all week, particularly Sunday and Monday under dark skies and again along shaded structure throughout the warmer afternoons later in the week.
Bitterroot River
Conditions
The Bitterroot is low, clear, and increasingly technical. The latest verified readings are approximately 203–207 CFS near Darby and 783–791 CFS near Missoula. The Bell Crossing gauge was around 384 CFS on the latest independently verified reading available earlier in the week.
The upper river is noticeably skinny. The middle and lower Bitterroot provide more forgiving water and remain the better general recommendation. Water was around 53 degrees midday heading into the weekend.
Where to Fish
- Soft inside seams
- Tailouts and foam lines
- Riffle transitions into deeper water
- Woody structure
- Deeper green lanes
- Soft buckets and shelves
How to Fish It
- Start late and let the water warm
- Look for BWOs on slow foam lines and back eddies Sunday and Monday
- Fish Mahogany Duns through midday
- Nymph Perdigons, Frenchies, Duracells, and Pheasant Tails through deeper seams while the water is cold
- Return to October Caddis in riffles and bank seams as afternoons warm later in the week
- Fish a single dry on a long leader when trout are visibly rising
- Work streamers along wood, drop-offs, soft banks, and deeper buckets
Top Patterns
- BWO dry / emerger, size 18–22
- Mahogany Dun, size 14–16
- October Caddis adult, size 8–12
- October Caddis pupa, size 8–12
- Frenchie, size 14–18
- Perdigon, size 16–20
- Pheasant Tail, size 16–20
- Olive or black Sculpzilla / Sparkle Minnow
Blackfoot River
Conditions
The Blackfoot near Bonner is around 580–586 CFS and holding close to its seasonal median. Water temperatures are around 49 degrees, so expect a slow start until the day warms.
The river is clear and concentrated into the better holding water. Fish the depth, structure, and oxygen rather than assuming every bank holds trout.
Where to Fish
- Deep pools
- Boulder seams
- Riffle transitions
- Deep inside banks
- Soft shelves below faster water
- Foam lines and slower tailouts during mayfly activity
How to Fish It
- Fish slow and deep during cold mornings
- Use Frenchies, Duracells, Perdigons, and stonefly nymphs in deeper runs
- Watch for BWOs when clouds persist
- Fish streamers through deep pools, ledges, and boulder seams
- Bring October Caddis back into the rotation as afternoons warm later in the week
- Keep casts deliberate in clear water
Top Patterns
- BWO dry, size 18–22
- Mahogany Dun, size 14–16
- October Caddis adult or pupa, size 8–12
- Frenchie, size 14–18
- Duracell, size 14–18
- Perdigon, size 16–20
- Pat's Rubber Legs / Zirdle, size 8–12
- Sparkle Minnow, Sculpzilla, or Thin Mint
Clark Fork River
Conditions
The Clark Fork is around 1,340–1,360 CFS above Missoula and roughly 2,110–2,130 CFS below Missoula. Water above town is around 50 degrees. The Clark Fork remains the best big-water choice and is carrying considerably more usable habitat than the smaller rivers.
The hatch of the week is the Blue-Winged Olive. Sunday's and Monday's cloudy, cold weather should give anglers the best chance to find fish working slowly in foam lines and slicks.
Where to Fish
- Slow foam lines
- Riffle edges
- Inside seams
- Tailouts
- Side-channel seams
- Deep green lanes
- Soft banks and woody structure
How to Fish It
- Look for BWO risers from noon through mid-afternoon Sunday and Monday
- Fish a single BWO dry on a long leader when targeting feeding fish
- Use Mahogany Duns around midday
- Fish stoneflies, worms, Frenchies, and Perdigons deeper when nothing is rising
- Bring October Caddis back into choppy riffles later in the week
- Streamer fish deeper banks and soft seams
Top Patterns
- BWO dry / emerger, size 18–22
- Mahogany Dun / cripple, size 14–16
- October Caddis, size 8–12
- Elk Hair Caddis / X-Caddis, size 14–18
- Frenchie / Perdigon, size 14–20
- Small stonefly nymph
- Sparkle Minnow, Peanut Envy, Thin Mint, or Mini Dungeon
Rock Creek
Conditions
Rock Creek near Clinton is around 230–235 CFS on the latest verified morning readings, with water around 48–50 degrees. It remains clear, low, and technical.
Sunday's weather may bring snow into the drainage, especially higher up. Fishing can still be good, but road conditions and access deserve more attention than they did during the warm stretch last week.
Where to Fish
- Deep riffle transitions
- Plunge pools
- Boulder pockets
- Tailouts
- Undercut banks
- Slow foam lines during BWO activity
How to Fish It
- Fish slowly and deeply during cold mornings
- Use small Perdigons, Frenchies, and stonefly nymphs
- Look for BWOs in tailouts and soft seams during cloudy periods
- Fish dark streamers through boulder runs and plunge pools
- Use October Caddis in the warmest part of the afternoon later in the week
- Keep wading deliberate in low, clear water
Top Patterns
- BWO, size 18–22
- Mahogany Dun, size 14–16
- October Caddis, size 8–12
- Perdigon, size 16–20
- Frenchie, size 14–18
- Small stonefly nymph
- Thin Mint, Woolly Bugger, or small olive / black streamer
West Fork of the Bitterroot
Conditions
The West Fork near Conner is approximately 82 CFS. This is extremely low water and substantially below the historical October 10 mean of roughly 139 CFS.
There are still fishable pockets, but this is not the general recommendation for most anglers. Expect concentrated fish, limited depth, and exceptionally clear water.
Where to Fish
- Deepest available pools
- Wood and boulder pockets
- Deeper riffle edges
- Protected tailouts
- Shaded water with adequate depth
How to Fish It
- Use long leaders and light tippet
- Stay out of productive water whenever possible
- Fish small BWO and mayfly patterns in softer water
- Use small nymphs through the deepest pockets
- Make one careful presentation before moving closer
- Consider the mainstem Bitterroot for a more forgiving day
Top Patterns
- BWO, size 18–22
- Mahogany Dun, size 14–16
- Small October Caddis, size 10–12
- Perdigon, size 16–20
- Pheasant Tail, size 16–20
- Small midge pattern, size 18–22
- Small olive streamer
Planning Note
Sunday: Rain, snow, and a high only in the low 40s. Start late. Fish BWOs, nymphs, and streamers. This may be the best true BWO weather of the week.
Monday: Another cold morning with temperatures recovering into the upper 40s. Expect the better fishing from noon through mid-afternoon.
Tuesday: Sunny and around the mid-50s. Nymph early, then look for Mahoganies and scattered October Caddis as the river warms.
Wednesday and Thursday: Sunshine and temperatures approaching 60. Expect a more balanced dry-dropper, Mahogany Dun, October Caddis, and streamer program.
Friday: Around the mid-60s. One of the better all-around fishing days of the week, with good midday mayfly potential and October Caddis in warmer riffles.
Saturday: Potentially around 70 degrees. Start later than you think, but expect a surprisingly active afternoon. October Caddis and dry-droppers should benefit from the warmth.
Overall: Sunday and Monday belong to BWOs, nymphs, and streamers. The second half of the week increasingly belongs to Mahoganies, October Caddis, dry-droppers, and patient technical fishing.
River Flow Snapshot – October 11, 2026
Values below are the freshest independently verified numerical readings available when this report was prepared. Most are from October 10. Bell Crossing's latest verified numerical reading available during research was from October 6. Gauge readings are provisional.
| River | Section | Gauge | Latest Verified Flow | Status |
|---|---|---|---|---|
| Bitterroot | Upper | Near Darby (12344000) | 203–207 CFS | Below Normal / Very Technical |
| Bitterroot | Middle | Bell Crossing nr Victor (12350250) | 384 CFS | Low / Latest Verified Earlier This Week |
| Bitterroot | Lower | Near Missoula (12352500) | 783–791 CFS | Near Seasonal Median / Best Bitterroot Volume |
| Blackfoot | Lower | Near Bonner (12340000) | 580–586 CFS | Near Median / Clear / Cold |
| Clark Fork | Upper | Above Missoula (12340500) | 1,340–1,360 CFS | Low but Fishable / 50°F Water |
| Clark Fork | Lower | Below Missoula (12353000) | 2,110–2,130 CFS | Best Big-Water Volume |
| Rock Creek | Lower | Near Clinton (12334510) | 230–235 CFS | Low / Clear / Wade Fishing Only |
| West Fork Bitterroot | Lower | Near Conner (12342500) | 82 CFS | Extremely Low / Highly Technical |
The lower Bitterroot and Clark Fork offer the most forgiving volume this week. The upper Bitterroot, Rock Creek, and especially the West Fork require considerably more stealth and attention to the deeper holding water.
Fly Box of the Week
Dry Flies
- BWO, size 18–22
- Mahogany Dun, size 14–16
- October Caddis, size 8–12
- Elk Hair Caddis, size 14–18
- X-Caddis, size 14–18
- Parachute Adams, size 16–20
- Hecuba, size 10–12
Nymphs
- Frenchie, size 14–18
- Perdigon, size 16–20
- Pheasant Tail, size 16–20
- Duracell, size 14–18
- BWO nymph, size 18–22
- October Caddis pupa, size 8–12
- Pat's Rubber Legs / Zirdle, size 8–12
Streamers
- Sparkle Minnow
- Sculpzilla
- Thin Mint
- Peanut Envy
- Mini Dungeon
- Woolly Bugger
- Small olive / black sculpin
Hatch and Fly Chart – Mid-October Edition
| Hatch / Insect | Activity | Best Time | Recommended Fly | Size |
|---|---|---|---|---|
| BWOs | Primary early-week hatch during clouds, rain, and snow | Noon–3:00 p.m. | Dry, emerger, cripple, or nymph | 18–22 |
| Mahogany Duns | Strong midday fall mayfly | Late morning–afternoon | Parachute Mahogany, cripple, emerger | 14–16 |
| October Caddis | Still active; improves again as afternoons warm later in the week | Afternoon | Adult or pupa | 8–12 |
| Small Caddis | Still present in riffles and broken water | Afternoon | Elk Hair Caddis, X-Caddis, pupa | 14–18 |
| Hecubas | Fading but still worth carrying | Midday | Hecuba / Brindlechute | 10–12 |
| Midges | Increasingly useful in cold, slow water | Late morning–afternoon | Midge larva, pupa, Griffith's Gnat | 18–24 |
The biggest hatch change is the decline of terrestrials. Do not build the day around hoppers anymore. BWOs and Mahoganies deserve the prime spots in the box, with October Caddis returning as a stronger afternoon option once temperatures climb later in the week.
Gear Picks of the Week
Warm Layers and Rain Gear
Sunday and Monday are legitimate cold-weather fishing days. Staying warm enough to fish the best afternoon window matters more than arriving first.
Long Leaders and Fine Tippet
Clear, low water makes presentation the entire game. Carry 4X through 6X and be willing to lengthen leaders for feeding fish.
Streamer Setup
The front creates one of the better streamer opportunities we have seen this fall. A dedicated streamer rod saves a lot of rig-changing when the light suddenly gets right.
Strategy and Expectations This Week
The middle and lower Bitterroot remain the best overall local recommendation. They provide more usable water than the upper river and offer a good mix of BWOs, Mahoganies, October Caddis, nymphing, and streamer fishing.
The Clark Fork may be the best dry-fly choice Sunday and Monday. Cold cloudy weather lines up well for BWOs, and the larger river offers more productive slow water for feeding fish.
The Blackfoot is a strong streamer and nymphing option. Just plan around the Weigh Station float closure.
Rock Creek remains excellent technical wade water. Low flows and cold water mean slower presentations and deeper runs are more important.
The West Fork remains extremely low. Recommend the mainstem Bitterroot for most anglers unless they specifically want challenging small-water fishing.
