Western Montana Fly Fishing Report
Regional River Conditions Overview
Western Montana rivers are high across the Bitterroot, Blackfoot, Clark Fork, Rock Creek, and West Fork of the Bitterroot after another runoff bump. The best bet this week is the Bitterroot system, especially the upper river, side channels, and softer bank water, but anglers need to treat the whole region as high-water fishing. The West Fork remains the cleanest smaller-water option, Rock Creek has salmonfly activity but difficult flows, and the Blackfoot and Clark Fork are big-water programs. Detailed river-by-river reports appear lower on the page.
Bitterroot River
Conditions
Water temp: 47–54°F. The Bitterroot is high and pushy, with the upper river near Darby around 3,620 CFS, Bell Crossing near Victor around 7,950 CFS, and the lower river near Missoula around 11,000 CFS. The river is not unfishable, but the main current is too heavy in many places. Fish only the softest usable water.
Where to Fish
- Side channels with walking-speed current
- Soft inside bends with depth
- Protected bank seams below current breaks
- Back-eddies and slow tailouts near structure
- Foam lines along calm inside banks
- Avoid fast outside bends and heavy mid-river current
How to Fish It
- Start with nymphs or streamers before looking for dries
- Use short, controlled drifts close to the bank
- Fish worms, stonefly nymphs, dark mayfly nymphs, and caddis larva in soft edges
- Use streamers tight to banks when visibility allows
- Switch to dries only when fish are clearly rising in calm water
- Float anglers should watch for debris, new wood, and changing side-channel lines
Top Patterns
- Stonefly nymph, size 6–10
- Worm pattern, red or wine
- Dark mayfly nymph, size 12–16
- Caddis larva or pupa, size 12–16
- BWO emerger, size 16–18
- PMD nymph or emerger, size 14–18
- Olive or black streamer, size 4–6
Blackfoot River
Conditions
Water temp: 50–52°F. The Blackfoot near Bonner is around 6,520 CFS and running strong. This is a big-water setup with limited wading options. The most consistent fishing will be subsurface, close to the bank, and in slower edge water.
Where to Fish
- Lower-river inside corners
- Soft shelves below heavy current
- Back-eddies with depth
- Banks and boulder edges with real current breaks
- Slower tailouts below structure
- Skip fast pocket water that cannot be controlled
How to Fish It
- Use heavy nymph rigs and short drifts
- Fish close to the bank
- Run stonefly nymphs, worms, and heavy attractor nymphs
- Streamer fish slower edges and buckets below structure
- Keep wading conservative and avoid unnecessary crossings
Top Patterns
- Stonefly nymph, size 6–10
- Worm pattern, red or wine
- Heavy attractor nymph
- Dark mayfly nymph, size 12–16
- Caddis larva, size 12–16
- Black or olive streamer, size 4–6
Clark Fork River
Conditions
Water temp: 50–52°F. The Clark Fork is big again, with the river above Missoula around 9,140 CFS and below Missoula around 19,900 CFS. The upper river has some fishable edge water, but the lower river is a serious-volume float scenario and not a casual wade-fishing option.
Where to Fish
- Soft edges above Missoula
- Protected bank seams below structure
- Backwater areas and side channels
- Slower shelves with depth
- Foam lines along calm inside banks
- Avoid the lower-river main push unless floating with experience
How to Fish It
- Nymph deep in softer edge water
- Fish streamers tight to banks and current breaks
- Use dry-dropper only when fish are feeding in calm edge water
- Avoid broad, fast current where drift control is impossible
- Look for trout tucked where current speed drops sharply
Top Patterns
- Stonefly nymph
- Worm pattern
- Sowbug-style pattern
- Dark mayfly nymph
- Caddis larva or pupa
- BWO or PMD emerger
- Olive or black streamer
Rock Creek
Conditions
Water temp: 47–52°F. Rock Creek near Clinton is around 2,020 CFS, which is high and technical. Salmonflies have started showing on the lower creek, and caddis, BWOs, PMDs, and other mayflies are in the mix, but high water still controls where fish can feed. This is not easy wading.
Where to Fish
- Lower-creek soft margins
- Inside bends with slower current
- Boulder edges with refuge water
- Back-eddies and bank pockets
- Protected tailouts during bug activity
- Avoid unnecessary crossings and fast mid-channel lanes
How to Fish It
- Nymph short through pocket-water edges
- Use streamers in softer bank water
- Fish salmonfly dries only where trout are using protected banks or willow-lined edges
- Watch for caddis, BWOs, PMDs, and salmonflies in softer water
- Wade carefully and fish fewer lanes better
Top Patterns
- Stonefly nymph, size 4–8
- Foam salmonfly dry, size 4–6
- Worm pattern
- BWO emerger, size 16–18
- PMD nymph or emerger, size 14–18
- Caddis larva or dry, size 12–16
- Black or olive streamer, size 4–6
West Fork of the Bitterroot
Conditions
Water temp: 45–51°F. The West Fork near Conner is around 912 CFS, which is still high but far more manageable than the mainstem Bitterroot. It may be the cleanest smaller-water option this week, but anglers should still fish it like high water and focus on soft structure.
Where to Fish
- Soft banks below Painted Rocks through Conner
- Protected tailouts with moderate current
- Inside seams with slower flow
- Edges below wood, boulders, and structure
- Calm seams during afternoon BWO, PMD, and caddis activity
- Avoid fast riffles and pushy mid-channel water
How to Fish It
- Nymph first and stay near the bottom
- Use heavier flies than normal for the West Fork
- Fish short, accurate drifts through soft water
- Watch for afternoon caddis, PMD, and BWO activity in protected seams
- Use 5X or 6X only when fish are clearly up and eating dries
- Keep wading conservative
Top Patterns
- Stonefly nymph
- Dark mayfly nymph
- Caddis larva or pupa
- BWO emerger, size 16–18
- PMD emerger, size 14–18
- Soft hackle, size 12–16
- Small olive streamer
Planning Note
Cool, wet weather early in the week may slow runoff temporarily, but warmer weather later in the week can push flows again. Fish late morning through mid-afternoon, watch the hydrographs, and prioritize water type over river loyalty.
The best plan is to start with the Bitterroot system, stay tight to soft edges, and adjust quickly if flows rise overnight. The West Fork is the cleanest smaller-water option, while Rock Creek is a high-water salmonfly gamble for experienced wade anglers.
River Flow Snapshot – May 31, 2026
Current gauge values are based on the latest available USGS readings reviewed for this weekly report.
| River | Section | Gauge | Flow (CFS) | Trend / Status |
|---|---|---|---|---|
| Bitterroot | Upper | Near Darby (12344000) | 3,620 | High / Rising |
| Bitterroot | Middle | Bell Crossing nr Victor (12350250) | 7,950 | High / Pushy |
| Bitterroot | Lower | Near Missoula (12352500) | 11,000 | Very High / Big Water |
| Blackfoot | Lower | Near Bonner (12340000) | 6,520 | High / Pushy |
| Clark Fork | Upper | Above Missoula (12340500) | 9,140 | High / Big Water |
| Clark Fork | Lower | Below Missoula (12353000) | 19,900 | Very High / Float Only |
| Rock Creek | Lower | Near Clinton (12334510) | 2,020 | High / Technical |
| West Fork Bitterroot | Upper | Below Painted Rocks (12342500) | 912 | High / Cleaner Option |
Flows are high across the region. The best fishing water this week is soft edge water, side channels, back-eddies, and protected seams close to the bank.
Fly Box of the Week
Dry Flies
- Foam salmonfly dry, size 4–6
- Caddis dry, size 12–16
- BWO dun, size 16–18
- BWO emerger, size 16–18
- PMD emerger or dry, size 14–18
- Large mayfly dry, size 10–12
Nymphs
- Stonefly nymph, size 4–10
- Worm pattern, red or wine
- Dark mayfly nymph, size 12–16
- Caddis larva or pupa, size 12–16
- Heavy attractor nymph
- BWO or PMD nymph, size 14–18
Streamers
- Olive streamer, size 4–6
- Black streamer, size 4–6
- Sculpin-style streamer, size 4–6
Hatch and Fly Chart – Early June Runoff Edition
| Hatch / Insect | Activity | Best Time | Recommended Fly | Size |
|---|---|---|---|---|
| Salmonflies | Starting on lower Rock Creek and building in select soft bank water | Midday to afternoon | Foam dry or stonefly nymph | 4–6 |
| Caddis | Active, best in calm edges and evening windows | Afternoon into evening | Dry, pupa, or larva | 12–16 |
| Blue-Winged Olive | Active in softer water and cloudy windows | Late morning to afternoon | Dun or emerger | 16–18 |
| PMD | Building as water temps stabilize in softer water | Late morning to afternoon | Nymph, emerger, or dry | 14–18 |
| March Brown / Larger Mayflies | Possible in protected seams and slower tailouts | Noon – 3 p.m. | Adult, emerger, or soft hackle | 10–14 |
Bugs are active, but high water still controls the fishing. Hatch activity matters most where trout can actually hold: soft banks, side channels, inside seams, calm tailouts, and protected back-eddies.
Gear Picks of the Week
6-Weight Rod
High flows, heavier nymph rigs, streamers, and larger salmonfly dries all favor a 6-weight this week. A 5-weight works in soft water, but the 6-weight gives better control.
Split Shot + Larger Indicators
Depth and drift control matter more than fly variety. Carry enough weight to get down quickly in short, controlled lanes.
Studded Boots + Wading Staff
Flows are high and banks are slick. Good traction and a wading staff are important for safe, controlled fishing this week.
Strategy and Expectations This Week
This is a high-water report with some real hatch potential, not an easy dry-fly report. Success this week means finding the slowest useful water, getting flies down quickly, and switching to dries only when fish are actively feeding in protected water.
The Bitterroot system gives anglers the best overall odds, but the West Fork is the cleanest smaller-water option. Rock Creek has salmonfly potential, but high water makes it a technical choice. A good day this week comes from careful water selection, safe wading, and realistic expectations.
