Tailwater · Mixed · Wyoming

Lewis River

Lewis River venue image

The Lewis River drains Lewis Lake down toward the Snake in the quiet southern end of Yellowstone, and its claim to fame is the channel between Lewis and Shoshone lakes, where big lake-run browns push up to spawn in the fall and draw anglers willing to wade cold water for a shot at a real fish.

Prime · Brown Trout
Sparkle Dun · 14-18
Primelive now
About as good as it gets
Low and clear — careful approach country. Take your time — read the water before you cast.
90% confidence
What moved it
  • LevelDry recentlyNo gauge reading
  • Water temp10.3°C
  • ClarityClear
Today's fly
SD
Sparkle Dun14-18
High-confidence seasonal pick
Conditions on the water
Estimate
Level
Dry recently
No gauge reading
Water temp10.3°C
ClarityClear
Weather13°C
WindSW 4 km/h
Pressure1020 hPa
Rain · recent0.2 mm
Rain · ahead0.0 mm

No gauge on this water — readings are regional estimates from weather, not a live gauge.

Water temperature for Brown Trout
Ideal
10°C est.ideal 1016°C
0°14°28°
How to fish it · for Brown Trout
When
Nymphing can work through most of the day.
Where
Cover mixed depths.
Method
Start with tight-line nymphs and adjust if fish rise or drift higher.
Kit
9 ft #4 rod, floating line, 12 ft tapered leader to 4–5 lb fluoro tippet.
Why this works
Excellent — water temperature is right today, though time of day could be better.
Hatch timeline · todayQuiet day

Hatch predictions

Today's headline hatch shown — see all 3 active hatches hour by hour with Pro.

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Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 3 guilds with Pro.

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 2 with Pro.

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Evidence
ModelledModerate confidence

Modelled from regional ecology — no survey or occurrence data for this water yet.

Through the year
0–3 scale · July highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Western Blue-Winged OliveHatch
2
3
3
3
3
3
3
3
2
Pale Morning DunHatch
2
3
3
2
TricoHatch
2
3
2
Black MidgeHatch
2
3
3
3
3
3
3
3
3
3
3
2

Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.

Ranked for today
Brown Trout fly box
Permits & access
Permit required — see local rules.
  • Yellowstone NP licence and special regulations
  • Handle spawning browns minimally — the fall run is the headline.
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 1
  1. Terrain map of the venue
    Terrain map
About this water

The Lewis River drains Lewis Lake down toward the Snake in the quiet southern end of Yellowstone, and its claim to fame is the channel between Lewis and Shoshone lakes, where big lake-run browns push up to spawn in the fall and draw anglers willing to wade cold water for a shot at a real fish. The river proper has meadow and canyon reaches with browns and brook trout. It's lake-fed water, so it runs clear and steady rather than flashing with the weather. Handle the spawning browns with the respect a spawning fish deserves.

  • Mixed
The full read · show the working · for Brown Trout · confidence 90%
How the 84 is built — score × weight = contribution
Temperature100 × 28%28.0
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time60 × 13%7.8
Pressure80 × 7%5.6
Insect activity64 × 12%7.7
Conditions total= 84
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
  • TroutSaturday of Memorial Day weekendFirst Sunday in November
Related guides
Booking & contacts