- Ecology: Good
- Chemical: Unknown
Rules at a glance
- Free fishing
- Fly only
Water temperature for Grayling
Warm — slow15°C est.ideal 4–14°C
0°14°28°
How to fish it · for Grayling
When
Midday window — grayling feed best from late morning into early afternoon.
Where
Work runs and glides — grayling shoal in the bottom third of the water column.
Method
Tight-line nymph the bottom third with weighted patterns.
Kit
10 ft #3 rod, floating line, long leader to 4 lb fluoro for nymphs.
Why this works
Fair — barometric pressure is working for you, but time of day is the limiting factor today.
Likely species
Mayflies
- Blue-winged oliveMost likely#16–18 · DunDuns are up; a sherry spinner fall may follow.
- Green drakeAlso possibleLower confidence#8–10 · DunDuns are up — the Spent Gnat spinners fall at dusk.
Hatch timeline · todayQuiet day
Hatch predictions
Today's headline hatch shown — see all 3 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.
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
1
Grayling seasonSeason
1
2
1
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Grayling fly box
Permits & access
Permit required — see local rules.
- Local iFiske permit required
- Good public access.
What's coming
Plan ahead
5-day outlook
Gallery · 2

Hedeviken September 2015 03 Terrain map
Water quality (WFD)
The full read · show the working · for Grayling · confidence 45%
How the 45 is built — score × weight = contribution
Temperature67 × 28%18.8
Flow28 × 22%6.2
Clarity45 × 18%8.1
Feeding Time10 × 13%1.3
Pressure80 × 7%5.6
Insect activity45 × 12%5.4
Conditions total= 45
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 4–14 °C ideal band — would lift the score and ease welfare.
A drop and clear would lift the flow and clarity scores.
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout 1 June → 31 August
- Grayling 1 June → 31 August
Related guides
Booking & contacts
Ljusnan

Water temperature for Grayling
Warm — slow15°C est.ideal 4–14°C
0°14°28°
How to fish it · for Grayling
When
Midday window — grayling feed best from late morning into early afternoon.
Where
Work runs and glides — grayling shoal in the bottom third of the water column.
Method
Tight-line nymph the bottom third with weighted patterns.
Kit
10 ft #3 rod, floating line, long leader to 4 lb fluoro for nymphs.
Why this works
Fair — barometric pressure is working for you, but time of day is the limiting factor today.
Likely species
Mayflies
- Blue-winged oliveMost likely#16–18 · DunDuns are up; a sherry spinner fall may follow.
- Green drakeAlso possibleLower confidence#8–10 · DunDuns are up — the Spent Gnat spinners fall at dusk.
Hatch timeline · todayQuiet day
Hatch predictions
Today's headline hatch shown — see all 3 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.
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
1
Grayling seasonSeason
1
2
1
GrannomHatch
2
2
Evening SedgeHatch
2
3
3
3
2
Large Dark OliveHatch
1
2
2
1
Iron BlueHatch
1
2
2
1
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Grayling fly box
Permits & access
Permit required — see local rules.
- Local iFiske permit required
- Good public access.
What's coming
Plan ahead
5-day outlook
Gallery · 2

Hedeviken September 2015 03 Terrain map
Water quality (WFD)
- Ecology: Good
- Chemical: Unknown
The full read · show the working · for Grayling · confidence 45%
How the 45 is built — score × weight = contribution
Temperature67 × 28%18.8
Flow28 × 22%6.2
Clarity45 × 18%8.1
Feeding Time10 × 13%1.3
Pressure80 × 7%5.6
Insect activity45 × 12%5.4
Conditions total= 45
Can you trust it?
Water temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Prey activitysurvey-backed invertebrate datasurvey
What would change the calculation
Cooler water — back toward the 4–14 °C ideal band — would lift the score and ease welfare.
A drop and clear would lift the flow and clarity scores.
The dawn and dusk windows score higher than the midday lull.
Directions
Seasons & zones
- Trout 1 June → 31 August
- Grayling 1 June → 31 August
Related guides
Booking & contacts