Rules at a glance
- Free fishing
- Fly only
Water temperature for Brown Trout
Warm — slow18.8°Cideal 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 18.8°C — above the brown trout caution line (18°C). Fish dawn or dusk only. Land it fast, wet hands, no air shots.
Likely species
Mayflies
Mayflies- Blue-winged oliveMost likely#16–18 · DunDuns are up; a sherry spinner fall may follow.
- Anglers curse mayfliesAlso possibleLower confidenceNearest relative#20–22 · SpinnerGo tiny: 20-22 spent spinner, single fly, long tippet.
- Turkey BrownAlso possibleLower confidence#14–16 · DunSmall spring dun on slower glides and margins.
- Late March BrownAlso possibleLower confidence#12–14 · DunLate-season upland riffle dun, dusk emergence.
Caddisflies
Caddisflies- Green SedgeMost likelyLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- Net-spinning caddis (S. Europe)Also possibleLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- Stone-case caddisAlso possibleLower confidenceNearest relative#14–16–18 · NymphTiny stone-cased larva; clean gravel riffles.
Damselflies & dragonflies
Damselflies & dragonflies- DamselfliesMost likelyNearest relative#10–12 · NymphSlow-retrieve a damsel nymph along the weed edges.
- Migrant HawkerAlso possibleLower confidence#6–8 · NymphStrip a big hawker nymph erratically near cover.
Hatch timeline · todayQuiet day
Hatch predictions
Today's headline hatch shown — see all 4 active hatches hour by hour as a supporter.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 3 guilds as a supporter.
Start free trial14-day free trial. Cancel anytime.
Evidence
Records-basedModerate confidence
Based on species-occurrence records, not local invertebrate surveys.
Through the year
0–3 scale · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
2
2
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Brown Trout
Top
6-10 · Pattern
High-confidence seasonal pick
Permits & access
Permit required — see local rules.
- RD Cerknica.
What's coming
Plan ahead
5-day outlook
Cooler water nearby · 2
Water here at 18.8°C — the fishing's alive, but these are cooler if you'd rather rest the warm water.
The full read · show the working · for Brown Trout · confidence 80%
How the 35 is built — score × weight = contribution
Temperature27 × 28%7.6
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity59 × 12%7.1
Conditions total= 64
Can you trust it?
Water temperaturelive gauge readinggauge
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
Directions
Seasons & zones
- Trout 1 March → 30 September
Related guides
Booking & contacts
Cerkniščica
Water temperature for Brown Trout
Warm — slow18.8°Cideal 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 18.8°C — above the brown trout caution line (18°C). Fish dawn or dusk only. Land it fast, wet hands, no air shots.
Likely species
Mayflies
- Blue-winged oliveMost likely#16–18 · DunDuns are up; a sherry spinner fall may follow.
- Anglers curse mayfliesAlso possibleLower confidenceNearest relative#20–22 · SpinnerGo tiny: 20-22 spent spinner, single fly, long tippet.
- Turkey BrownAlso possibleLower confidence#14–16 · DunSmall spring dun on slower glides and margins.
- Late March BrownAlso possibleLower confidence#12–14 · DunLate-season upland riffle dun, dusk emergence.
Caddisflies
- Green SedgeMost likelyLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- Net-spinning caddis (S. Europe)Also possibleLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
- Stone-case caddisAlso possibleLower confidenceNearest relative#14–16–18 · NymphTiny stone-cased larva; clean gravel riffles.
Damselflies & dragonflies
- DamselfliesMost likelyNearest relative#10–12 · NymphSlow-retrieve a damsel nymph along the weed edges.
- Migrant HawkerAlso possibleLower confidence#6–8 · NymphStrip a big hawker nymph erratically near cover.
Hatch timeline · todayQuiet day
Hatch predictions
Today's headline hatch shown — see all 4 active hatches hour by hour as a supporter.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
Top nymph shown — see all 3 guilds as a supporter.
Start free trial14-day free trial. Cancel anytime.
Evidence
Records-basedModerate confidence
Based on species-occurrence records, not local invertebrate surveys.
Through the year
0–3 scale · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Trout seasonSeason
1
2
2
2
2
2
1
Evening SedgeHatch
2
3
3
3
2
Alpine RhithrogenaHatch
1
2
2
1
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
2
2
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Brown Trout
Top
6-10 · Pattern
High-confidence seasonal pick
Permits & access
Permit required — see local rules.
- RD Cerknica.
What's coming
Plan ahead
5-day outlook
Cooler water nearby · 2
Water here at 18.8°C — the fishing's alive, but these are cooler if you'd rather rest the warm water.
The full read · show the working · for Brown Trout · confidence 80%
How the 35 is built — score × weight = contribution
Temperature27 × 28%7.6
Flow80 × 22%17.6
Clarity95 × 18%17.1
Feeding Time70 × 13%9.1
Pressure80 × 7%5.6
Insect activity59 × 12%7.1
Conditions total= 64
Can you trust it?
Water temperaturelive gauge readinggauge
Level / flowon-river gaugeobserved
Prey activitymodelled from regional profilemodelled
What would change the calculation
Cooler water — back toward the 10–16 °C ideal band — would lift the score and ease welfare.
Directions
Seasons & zones
- Trout 1 March → 30 September
Related guides
Booking & contacts