High-altitude side valleys of the Valais holding small mountain streams with wild brown trout. Very short season—typically June to September. Intimate pocket water with tight-line nymphing.
- Granite
Water temperature for Brown Trout
Warm — slow22°C est.ideal 10–16°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
Water at 22.4°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Hatch timeline · todayPeak at 6am
Hatch predictions
Today's headline hatch shown — see all 2 active hatches hour by hour with Pro.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 2 guilds with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 2 with Pro.
Start free trial14-day free trial. Cancel anytime.
Evidence
Survey-backed · regionalModerate confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
1
March BrownHatch
2
3
2
GrannomHatch
2
2
Large StoneflyHatch
2
3
2
Yellow SallyHatch
2
3
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Brown Trout fly box
A compact but high-quality Swiss box covering alpine streams, mountain lakes, and Jura salmonid rivers such as the Doubs.
6-10 · Pattern
Swing
Permits & access
Permit required — see local rules.
- Valais Canton high-altitude streams
- Patent (Valais) + permit required
- Remote locations.
What's coming
Plan ahead
5-day outlook
Water here around 22°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
Stream above Binn VS Terrain map
About this water
The full read · show the working · for Brown Trout · confidence 90%
How the 8 is built — score × weight = contribution
Temperature4 × 28%1.1
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time60 × 13%7.8
Pressure80 × 7%5.6
Insect activity55 × 12%6.6
Limiting factor: Water temperature (22.4°C) is outside Brown Trout's preferred range (10–16°C)= 56
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowproxy via Arc (Bessans reach)proxy
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout June → 30 September
Related guides
Booking & contacts
Valais Alpine Streams
High-altitude side valleys of the Valais holding small mountain streams with wild brown trout.
Water temperature for Brown Trout
Warm — slow22°C est.ideal 10–16°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
Water at 22.4°C. This is the line where catch-and-release kills brown trout. Do not fish for them today.
Hatch timeline · todayPeak at 6am
Hatch predictions
Today's headline hatch shown — see all 2 active hatches hour by hour with Pro.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 2 guilds with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 2 with Pro.
Start free trial14-day free trial. Cancel anytime.
Evidence
Survey-backed · regionalModerate confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
1
March BrownHatch
2
3
2
GrannomHatch
2
2
Large StoneflyHatch
2
3
2
Yellow SallyHatch
2
3
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Brown Trout fly box
A compact but high-quality Swiss box covering alpine streams, mountain lakes, and Jura salmonid rivers such as the Doubs.
6-10 · Pattern
Swing
Permits & access
Permit required — see local rules.
- Valais Canton high-altitude streams
- Patent (Valais) + permit required
- Remote locations.
What's coming
Plan ahead
5-day outlook
Water here around 22°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
Stream above Binn VS Terrain map
About this water
High-altitude side valleys of the Valais holding small mountain streams with wild brown trout. Very short season—typically June to September. Intimate pocket water with tight-line nymphing.
- Granite
The full read · show the working · for Brown Trout · confidence 90%
How the 8 is built — score × weight = contribution
Temperature4 × 28%1.1
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time60 × 13%7.8
Pressure80 × 7%5.6
Insect activity55 × 12%6.6
Limiting factor: Water temperature (22.4°C) is outside Brown Trout's preferred range (10–16°C)= 56
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowproxy via Arc (Bessans reach)proxy
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout June → 30 September
Related guides
Booking & contacts