Main Stem Snake River
MAIN STEM SNAKE RIVER
ReportAUG 4 — 11, 2026
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Flow
2720CFS
SNAKE RIVER NR BLACKFOOT ID
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Water Temp
56.3°F
Updated 2026-08-04
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Weather
52–91°F
Areas Of Smoke
🎣
Reported By
Bruce Staples
On the water
Cool spring inflows from the Fort Hall Reservation are keeping the upper reach fishable; flow below American Falls Dam is running around 10,000 cfs — ideal for boating but dangerous for waders. Water temperature at the Blackfoot gauge is 56.3°F (2,720 cfs), with smoky skies and highs in the mid-to-upper 80s through midweek.
From the ShopBruce Staples · August 4, 2026
The best fly fishing above the reservoir is from Tilden Bridge down to the reservoir (take out at McTucker launch site) because of cool inflow from numerous springs, mostly coming in from the Fort Hall Reservation. Boating is the safest and most effective way to fish.
Streamer and woolly bugger patterns on sink tip or full sinking lines with stout leaders are the best producers under these conditions. All boat launches are open. Flow below American Falls Dam is about 10,000 cfs, so wading there is dangerous. This flow is ideal for boating and makes all launch sites easily accessible.
What's Working — Hot Flies
Hatch Chart
| Insect | Size | Activity | Prime Time |
|---|---|---|---|
| Baitfish / Sculpin | #4–6 | All day | Early morning & evening |
| Leeches | #8–14 | Consistent subsurface | Morning & low-light |
| Terrestrials (Hoppers, Ants) | #10–16 | Seasonal — August | Midday to afternoon |
Best Time Window
- EARLY MORNING (first light to 9 AM): Prime streamer window — fish are most aggressive before the August heat builds; work the spring-cooled seams hard from the boat.
- MIDDAY TO AFTERNOON (10 AM to 4 PM): Maintain streamer presentations on sinking lines in deeper runs; smoke and heat may slow surface activity but subsurface action continues.
- EVENING (5 PM to dark): Second peak for streamer and woolly bugger patterns as light drops and fish move shallower along the banks.
Guide's Tip
From the benchRig a sink tip or full sinking line with a short, stout leader — 2–3 feet of heavy fluorocarbon — to get your streamer or woolly bugger down fast in the current. The McTucker launch site is your take-out; plan your float from Tilden Bridge and work the banks near the spring inflows from the Fort Hall Reservation side. Note: if you're fishing below American Falls Dam, do not wade — flows there are around 10,000 cfs and extremely dangerous.
Main Species
Brown Trout
Rainbow Trout
Yellowstone Cutthroat Trout
