Southwest Montana, Montana
Big Hole River Fishing Report: May 16, 2026
The Big Hole is falling near Melrose but still in runoff mode, with streamer and worm tactics more reliable than technical dry-fly fishing.
- Status
- tough
- Flow trend
- falling
- Best window
- Short afternoon windows between weather and flow changes
- Best methods
- streamers, nymphs
Quick Summary
The Big Hole is fishable only in the right places and windows. USGS showed 2,950 cfs near Melrose, down about 260 cfs over the last day, but the drainage is still in a runoff pattern. Expect changing clarity, bank-oriented fish, and weather-driven swings rather than a stable hatch program.
Conditions Snapshot
| Field | Value |
|---|---|
| Status | Tough |
| Flow | 2,950 cfs near Melrose at 3:15 PM MDT |
| Water Temp | 51 F near Melrose |
| Clarity | Variable; local reports noted better visibility upstream than around Melrose |
| Trend | Falling |
| Best Window | Short afternoon windows between weather and flow changes |
| Best Method | streamers; nymphs |
| Wadeability | Limited; runoff conditions and cold storms require caution |
Weather
Melrose had a cool, windy afternoon with showers and thunder possible, west-northwest wind near 18 mph, and gusts near 29 mph. Tonight turns colder with rain and snow likely, then Sunday stays cold with snow showers possible.
River Notes
Falling water helps, but runoff rivers can change fast. Fish soft banks, inside bends, and structure where trout can slide out of heavy current. If new rain or snowmelt muddies the river, move upstream, look for clearer tributary influence, or wait for visibility to improve.
Hatch Activity
| Hatch | Size | Notes |
|---|---|---|
| Caddis | Not reported | Possible, but not the main driver in runoff water |
| Stoneflies | 6-10 | Nymphs are more useful than dries today |
Recommended Flies
| Category | Fly | Size | Notes |
|---|---|---|---|
| Streamer | Sparkle Minnow | 6 | Work banks and softer buckets |
| Streamer | Yellow Dungeon | 4-6 | Use where water has color |
| Nymph | San Juan Worm | 10-12 | Good high-water attractor |
| Nymph | Stonefly nymph | 6-10 | Fish near bottom along edges |
| Nymph | Wonky Worm | 12 | Use in softer seams |
Tactics
Think high-water edges. Keep casts tight to banks, slow the fly down, and avoid long wades. Streamers and worm or stonefly nymph rigs are the best tools until clarity and flows settle.
Gauge Links
| Gauge | Flow | Temp | Link |
|---|---|---|---|
| Big Hole River near Melrose MT | 2,950 cfs | 51 F | USGS 06025500 |
Sources
Official sources checked: USGS station 06025500 and the National Weather Service forecast for the Melrose, MT area. This report is an original Custom FlyBox summary based on current official gauge and weather data, with local public conditions reports reviewed separately for hatch, access, and method context.