Western Montana Fly Fishing Report
Flow Update
The recent precipitation has improved flows across most of the region.
Rock Creek is up substantially, the Clark Fork has gained meaningful water, and the Bitterroot and Blackfoot have also responded. That additional water creates more usable holding habitat and should improve streamer fishing as the weather turns colder and wetter.
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 River: The construction-related floating closure below Weigh Station has been lifted.
- Rock Creek: Fishing from boats or vessels remains prohibited through November 30. Wade fishing only.
- Bitterroot, Clark Fork, and West Fork: No current emergency angling restrictions affecting our normal fishing areas.
- Fall reminder: Watch for active spawning gravel and avoid walking through or fishing directly over redds.
Regional River Conditions Overview
The late-week precipitation produced a welcome increase in flows. The Clark Fork above Missoula is now close to 2,000 CFS, the lower river is around 2,850 CFS, Rock Creek has climbed above 400 CFS, and the Blackfoot is above 700 CFS.
The Bitterroot has also responded, particularly through the middle river. The upper Bitterroot remains relatively low, but the additional water should spread fish into more usable holding areas than we had last week.
The weather becomes the dominant factor after Monday. Rain arrives Monday night, followed by rain and snow Tuesday and additional unsettled weather through the remainder of the week. That pattern should favor BWOs, midges, nymphs, and streamers.
Cold overnight temperatures mean the best fishing window remains late morning through afternoon. There is almost no advantage to being on the river at daylight right now.
Bitterroot River
Conditions
The Bitterroot received a useful flow bump. Current readings are around 269 CFS near Darby, 568 CFS near Victor, and approximately 942 CFS near Missoula.
The middle and lower river remain the best general recommendations. The increase in water should improve holding habitat around riffles, seams, side channels, deeper buckets, and structure.
Where to Fish
- Riffle transitions into deeper water
- Foam lines and inside seams
- Slow tailouts
- Deep buckets and shelves
- Wood and shaded structure
- Side channels with meaningful depth and current
How to Fish It
- Start late and concentrate on deeper water until the river warms
- Nymph Frenchies, Perdigons, Pheasant Tails, Duracells, and BWO nymphs through deeper seams
- Watch for BWOs and Mahogany Duns from late morning through afternoon
- Fish midges in slower foam lines and tailouts
- Carry October Caddis for warmer riffles Sunday and Monday
- Use long leaders and fine tippet when fish are visibly rising
- Give streamers significant time once clouds and precipitation arrive
Top Patterns
- BWO dry / emerger, size 18–22
- Mahogany Dun, size 14–16
- October Caddis, size 8–12
- Griffith's Gnat, size 18–22
- Frenchie, size 14–18
- Perdigon / Pheasant Tail, size 16–20
- Duracell, size 14–18
- Sparkle Minnow, Sculpzilla, Thin Mint, or olive sculpin
Blackfoot River
Conditions
The Blackfoot near Bonner is around 712 CFS, up substantially from the roughly 580–590 CFS range we saw last week. The river remains cold, but the additional water creates more usable depth around boulders, banks, riffles, and buckets.
Where to Fish
- Boulder seams
- Deep pools
- Riffle transitions
- Deep inside bends
- Willow-lined banks with depth
- Soft shelves below heavier current
How to Fish It
- Fish slow and deep during cold mornings
- Use Pat's Rubber Legs or Zirdles followed by smaller mayfly nymphs
- Watch for BWOs in soft seams during cloudy weather
- Fish October Caddis Sunday and Monday during warmer afternoon periods
- Use Zebra Midges and small Perdigons as water temperatures drop
- Streamer fish boulder seams, deeper banks, and buckets
- Slow the retrieve and add pauses as the water cools
Top Patterns
- BWO, size 18–22
- Mahogany Dun, size 14–16
- October Caddis, size 8–12
- Pat's Rubber Legs / Zirdle, size 8–12
- Frenchie / Duracell, size 14–18
- Perdigon, size 16–20
- Zebra Midge, size 18–22
- Sparkle Minnow, Sculpzilla, Thin Mint, or Woolly Bugger
Clark Fork River
Conditions
The Clark Fork received one of the more significant flow increases. Current readings are around 1,991 CFS above Missoula and approximately 2,857 CFS below Missoula.
This is now the most forgiving big-water option in the region. The additional flow creates better holding water through riffles, foam lines, inside seams, side channels, and deeper green lanes.
Where to Fish
- Slow foam lines
- Riffle edges
- Inside seams
- Tailouts and slicks
- Side-channel seams
- Current tongues
- Deep green lanes
How to Fish It
- Spend time watching before casting when trout are rising
- Fish BWOs on long leaders in slow foam lines
- Carry Mahogany Duns for midday surface feeding
- Nymph Frenchies, Perdigons, Pheasant Tails, midges, and small stoneflies through deeper seams
- Use October Caddis Sunday and Monday during warmer periods
- Fish streamers along banks, shelves, wood, and soft inside water once clouds arrive
Top Patterns
- BWO Comparadun / emerger, size 18–22
- Mahogany Dun, size 14–16
- October Caddis, size 8–12
- Griffith's Gnat, size 18–22
- Frenchie / Perdigon, size 14–20
- Pheasant Tail, size 16–20
- Sparkle Minnow, Peanut Envy, Kreelex, or Mini Dungeon
Rock Creek
Conditions
Rock Creek near Clinton is around 428 CFS this morning, a major increase from the roughly 240–265 CFS range we had been seeing. That additional water dramatically changes the creek compared with last week.
Expect more depth, stronger current, and better streamer water. Depending on precipitation and runoff, anglers should also pay attention to clarity before committing to smaller technical dries.
Where to Fish
- Deep boulder pockets
- Plunge pools
- Riffle drops
- Soft seams
- Undercut banks
- Tailouts during mayfly activity
- Newly formed soft edges beside heavier current
How to Fish It
- Fish the softer edges created by the higher flow
- Use Frenchies, Perdigons, Pheasant Tails, and small stonefly nymphs
- Watch for BWOs in tailouts and slower seams
- Carry Mahogany Duns and midges
- Give streamers more time than you did last week
- Fish darker or slightly larger streamers if water picks up color
- Remember fishing from boats or vessels is prohibited through November 30
Top Patterns
- BWO dry / emerger, size 18–22
- Mahogany Dun, size 14–16
- Frenchie / Perdigon, size 14–20
- Pheasant Tail, size 16–20
- Small stonefly nymph
- Zebra Midge, size 18–22
- Thin Mint, Woolly Bugger, Sparkle Minnow, or olive / black sculpin
West Fork of the Bitterroot
Conditions
The West Fork near Conner is around 57 CFS. Unlike the rest of the system, it remains extremely low and has dropped further from last week's already-low reading.
This is very technical water. Fish will be concentrated into the deepest available pools and pockets, and any careless approach can shut down productive water quickly.
Where to Fish
- Deepest pools
- Wood and boulder pockets
- Protected tailouts
- Deep riffle edges
- Shaded water with adequate depth
How to Fish It
- Use long leaders and fine tippet
- Stay out of productive water whenever possible
- Fish BWOs and midges in softer water
- Use small Perdigons and Pheasant Tails through deeper pockets
- Make one careful presentation before moving closer
- Consider the mainstem Bitterroot for a more forgiving day
Top Patterns
- BWO, size 18–22
- Griffith's Gnat, size 18–22
- Zebra Midge, size 18–22
- Perdigon, size 16–20
- Pheasant Tail, size 16–20
- Mahogany Dun, size 14–16
- Small olive streamer
Planning Note
Sunday: Mostly sunny with a high around 52. A comfortable fall fishing day. Start around 11:00 and look for Mahoganies, BWOs, October Caddis, nymphs, and streamers through the afternoon.
Monday: Mostly cloudy with a high around 53. Rain develops late. This could become an excellent streamer afternoon as the front approaches.
Tuesday: Rain and snow with a high around 45. One of the best BWO, nymph, and streamer days of the week. Dress for it and fish the warmest part of the day.
Wednesday: High near 48 with another chance of rain. Expect good midday BWO and nymph activity.
Thursday: Chance of rain and snow with temperatures in the mid-40s. Continue focusing on BWOs, midges, nymphs, and slow streamers.
Friday: Another cool, unsettled day around the mid-40s. Fishing should remain concentrated around the middle of the day.
Saturday: Halloween brings another chance of rain and snow with a high around 44. Start late and fish deeper water until insect activity develops.
Overall strategy: Sunday and Monday offer the easier weather. Tuesday through Saturday offer the more interesting fishing weather. If you want BWOs and streamers, embrace the ugly days.
River Flow Snapshot – October 25, 2026
Values are the latest Northwest River Forecast Center observations reviewed the morning of October 25. Gauge readings are provisional and can change throughout the day.
| River | Section | Gauge | Current Flow | Status |
|---|---|---|---|---|
| Bitterroot | Upper | Near Darby (12344000) | 269 CFS | Rising / Improved |
| Bitterroot | Middle | Near Victor / Bell Crossing (12350250) | 568 CFS | Strong Improvement |
| Bitterroot | Lower | Near Missoula (12352500) | 942 CFS | Improved / Good Fall Volume |
| Blackfoot | Lower | Near Bonner (12340000) | 712 CFS | Rising / Better Holding Water |
| Clark Fork | Upper | Above Missoula (12340500) | 1,991 CFS | Strong Improvement |
| Clark Fork | Lower | Below Missoula (12353000) | 2,857 CFS | Best Big-Water Volume |
| Rock Creek | Lower | Near Clinton (12334510) | 428 CFS | Major Flow Increase |
| West Fork Bitterroot | Lower | Near Conner (12342500) | 57 CFS | Extremely Low / Highly Technical |
The flow increase changes the regional picture in a positive way. The Clark Fork, Blackfoot, middle Bitterroot, and Rock Creek all have substantially more usable water than they did last week. The West Fork remains the clear exception.
Fly Box of the Week
Dry Flies
- BWO, size 18–22
- Mahogany Dun, size 14–16
- Parachute Adams, size 16–20
- Purple Haze, size 16–20
- Griffith's Gnat, size 18–22
- October Caddis, size 8–12
- Small caddis, 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
- Pat's Rubber Legs / Zirdle, size 8–12
Streamers
- Sparkle Minnow
- Sculpzilla
- Thin Mint
- Mini Dungeon
- Peanut Envy
- Woolly Bugger
- Olive / black sculpin
Hatch and Fly Chart – Halloween Week Edition
| Hatch / Insect | Activity | Best Time | Recommended Fly | Size |
|---|---|---|---|---|
| BWOs | Primary hatch during the week's cloudy, wet weather | Late morning–afternoon | Dry, emerger, cripple, or nymph | 18–22 |
| Mahogany Duns | Still important but gradually fading | Midday | Mahogany dry, cripple, or emerger | 14–16 |
| Midges | Increasingly important in colder water | Late morning–afternoon | Griffith's Gnat, Zebra Midge, larva or pupa | 18–24 |
| October Caddis | Fading but still relevant Sunday and Monday | Warmest part of afternoon | Adult or pupa | 8–12 |
| Small Caddis | Scattered activity around riffles | Afternoon | Elk Hair Caddis, X-Caddis, pupa | 14–18 |
| Terrestrials | Essentially finished as a primary strategy | Occasional warm afternoon | Ant or beetle | 14–18 |
BWOs and midges now deserve the prime positions in the late-season box. Mahogany Duns remain relevant, and October Caddis can still move fish Sunday and Monday, but the colder weather from Tuesday onward should push the fishing increasingly toward smaller mayflies, nymphs, midges, and streamers.
Gear Picks of the Week
Waterproof Layers
The best fishing weather this week may also be the least pleasant weather. Good rain gear means you can stay through the midday hatch rather than retreating to the truck just as things get interesting.
4X–6X Tippet
Clear fall water and selective BWO fish still demand fine tippet and careful presentations, even with the recent flow increase.
Streamer Setup
The combination of more water, clouds, rain, and colder conditions makes this a good week to keep a dedicated streamer rod rigged.
Strategy and Expectations This Week
The middle and lower Bitterroot remain the best overall local recommendation. More water improves the river compared with last week, and the hatch and streamer mix remains excellent.
The Clark Fork may be the most interesting river of the week. Nearly 2,000 CFS above Missoula combined with several days of cloudy, wet weather creates a strong BWO and streamer setup.
Rock Creek received the most dramatic improvement. The jump to more than 400 CFS provides more depth and significantly better streamer water while remaining a wade-fishing-only option.
The Blackfoot is another strong streamer choice. Increased flow improves deeper banks, buckets, and boulder seams.
The West Fork is still extremely low. Recommend the mainstem Bitterroot for most anglers unless they specifically want difficult technical small-water fishing.
