- Ecology: Unknown
- Chemical: Unknown
Water temperature for Atlantic Salmon
Welfare risk22°C est.ideal 10–14°C
0°14°28°
How to fish it · for Atlantic Salmon
When
Morning into early afternoon.
Where
Pool tails, steadier runs, and any water with pace.
Method
Fish a sensible line-and-fly combination for the height and pace of water.
Kit
13 ft #8/9 double-hander in spate, 10 ft #8 single in low water. Floating line plus a fast-sink tip. 12–15 lb fluoro tippet.
Why this works
Water at 22.2°C. This is the line where catch-and-release kills atlantic salmon. Do not fish for them today.
Hatch timeline · todayQuiet day
Hatch predictions
See the full hour-by-hour hatch timeline with Pro.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
See the full sub-surface read with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 3 with Pro.
Start free trial14-day free trial. Cancel anytime.
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
Salmon runRun
1
2
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
Atlantic Salmon fly box
tube medium to long · Swing
Long-hackled, high-movement tube pattern well suited to the bigger, often more coloured volume typical of southern Norway's regulated rivers.
Beats · 4 · 3 reaches
Numedalslågen is a long southern salmon river managed as a chain of named beats and club/member waters under the Numedalslågen forvaltningslag, knitted together by the national fee and reach-specific seasons. To fish here you generally need three things stacked together: the national fishing fee (fiskeravgift), which funds salmon management and does NOT by itself grant access to any water; a local beat, club or zone permit (via Elveguiden, Inatur or the controller pages); and compliance with the 2026 reach rules — the lower river to Holmfoss opens 15 May, the upper river to Hvittingfoss opens 1 June, a one-fish daily quota applies, side-water fishing is banned except the Hagnesvassdraget, and fish must not be released above 18°C. Holmfoss is the key regulatory boundary. Above all, the season is subject to a mid-July evaluation that can extend, tighten or stop fishing — confirm status, quota and your booking route with the forvaltningslag before you travel.
Lower river — Larvik / mouth to HolmfossSeason rods
The lower river from the sea at Larvik up to Holmfoss takes the early run and opens first — 15 May to 8 August.
Upper river — later-season fly water (Holmfoss–Hvittingfoss) · 2 beatsDay rods
Upper river — Holmfoss to Hvittingfoss, Brufoss — named fly water
The 2 beats
Upper river — Holmfoss to HvittingfossSeason rods
Numedalslågen forvaltningslag / upper-river clubs
Above Holmfoss to Hvittingfoss the river opens later — 1 June to 24 August — and holds the named fly water at Brufoss plus major salmon lies at Kjærrafossen, Naugfossen and Hoggtveita. Holmfoss is the regulatory boundary between this reach and the lower river. Access is by beat, club or zone permit.
Fiskeravgift + local permit. 2026: season 1 June–24 August; daily quota 1 fish; side-water fishing banned except Hagnesvassdraget; no release above 18°C. Subject to mid-season evaluation.
Brufoss — named fly waterDay tickets
Local Brufoss permit / Numedalslågen forvaltningslag
Brufoss is the best-known fly-fishing focus on Numedalslågen, a named water in the upper Holmfoss–Hvittingfoss reach where salmon typically arrive in late June. A practical day-card / local-permit candidate rather than a premium private beat — a good option for the visiting fly angler. Sits within the upper reach's 1 June–24 August season.
Fiskeravgift + local Brufoss/forvaltningslag permit. 2026 upper-reach season 1 June–24 August; daily quota 1 fish; no release above 18°C; side-water fishing banned except Hagnesvassdraget. Subject to mid-season evaluation.
Kjærrafossen & falls — migration timing contextEnquiry
The falls and named pools — Kjærrafossen, Naugfossen and Hoggtveita — are the migration markers that explain when upper-river water comes good.
Permits & access
Permit required — see local rules.
- Fiskeravgift (national fee) PLUS local permit required for anadromous fishing
- Lower river (to Holmfoss) opens 15 May; upper river (Holmfoss–Hvittingfoss) opens 1 June
- Daily quota 1 fish
- Side-water fishing banned except Hagnesvassdraget
- Rules subject to mid-season evaluation and may be extended, restricted or stopped.
What's coming
Plan ahead
5-day outlook
Water here around 22°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
Numedalslågen in the autumn Terrain map
Water quality (WFD)
Why this score · for Atlantic Salmon
- Temperature030% weight
- Flow9025% weight
- Clarity7520% weight
- Feeding Time9015% weight
- Pressure8510% weight
Directions
Seasons & zones
- Salmon15 May (mouth to Holmfoss); 1 June (Holmfoss to Hvittingfoss) → 8 August (mouth to Holmfoss); 24 August (Holmfoss to Hvittingfoss)
- TroutOpens Variable — typically June onward
Salmon: Open (2026) — Salmon fishing open in 2026 under Numedalslågen forvaltningslag management. Miljødirektoratet confirmed 2026 rule changes in April 2026. A mid-season evaluation in mid-July may extend, tighten or stop fishing depending on in-season returns; returns >50% below target halt fishing.
Sea trout: Open (2026) — Sea trout present and fishable under the same local permit and seasonal framework; confirm reach-specific rules locally.
Related guides
Booking & contacts
Numedalslågen
Water temperature for Atlantic Salmon
Welfare risk22°C est.ideal 10–14°C
0°14°28°
How to fish it · for Atlantic Salmon
When
Morning into early afternoon.
Where
Pool tails, steadier runs, and any water with pace.
Method
Fish a sensible line-and-fly combination for the height and pace of water.
Kit
13 ft #8/9 double-hander in spate, 10 ft #8 single in low water. Floating line plus a fast-sink tip. 12–15 lb fluoro tippet.
Why this works
Water at 22.2°C. This is the line where catch-and-release kills atlantic salmon. Do not fish for them today.
Hatch timeline · todayQuiet day
Hatch predictions
See the full hour-by-hour hatch timeline with Pro.
Start free trial14-day free trial. Cancel anytime.
Sub-surface · on the nymphunder the surface
Hatch predictions
See the full sub-surface read with Pro.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey
Hatch predictions
Top prey shown — see all 3 with Pro.
Start free trial14-day free trial. Cancel anytime.
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
Salmon runRun
1
2
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
Atlantic Salmon fly box
tube medium to long · Swing
Long-hackled, high-movement tube pattern well suited to the bigger, often more coloured volume typical of southern Norway's regulated rivers.
Beats · 4 · 3 reaches
Numedalslågen is a long southern salmon river managed as a chain of named beats and club/member waters under the Numedalslågen forvaltningslag, knitted together by the national fee and reach-specific seasons. To fish here you generally need three things stacked together: the national fishing fee (fiskeravgift), which funds salmon management and does NOT by itself grant access to any water; a local beat, club or zone permit (via Elveguiden, Inatur or the controller pages); and compliance with the 2026 reach rules — the lower river to Holmfoss opens 15 May, the upper river to Hvittingfoss opens 1 June, a one-fish daily quota applies, side-water fishing is banned except the Hagnesvassdraget, and fish must not be released above 18°C. Holmfoss is the key regulatory boundary. Above all, the season is subject to a mid-July evaluation that can extend, tighten or stop fishing — confirm status, quota and your booking route with the forvaltningslag before you travel.
Lower river — Larvik / mouth to HolmfossSeason rods
The lower river from the sea at Larvik up to Holmfoss takes the early run and opens first — 15 May to 8 August.
Upper river — later-season fly water (Holmfoss–Hvittingfoss) · 2 beatsDay rods
Upper river — Holmfoss to Hvittingfoss, Brufoss — named fly water
The 2 beats
Upper river — Holmfoss to HvittingfossSeason rods
Numedalslågen forvaltningslag / upper-river clubs
Above Holmfoss to Hvittingfoss the river opens later — 1 June to 24 August — and holds the named fly water at Brufoss plus major salmon lies at Kjærrafossen, Naugfossen and Hoggtveita. Holmfoss is the regulatory boundary between this reach and the lower river. Access is by beat, club or zone permit.
Fiskeravgift + local permit. 2026: season 1 June–24 August; daily quota 1 fish; side-water fishing banned except Hagnesvassdraget; no release above 18°C. Subject to mid-season evaluation.
Brufoss — named fly waterDay tickets
Local Brufoss permit / Numedalslågen forvaltningslag
Brufoss is the best-known fly-fishing focus on Numedalslågen, a named water in the upper Holmfoss–Hvittingfoss reach where salmon typically arrive in late June. A practical day-card / local-permit candidate rather than a premium private beat — a good option for the visiting fly angler. Sits within the upper reach's 1 June–24 August season.
Fiskeravgift + local Brufoss/forvaltningslag permit. 2026 upper-reach season 1 June–24 August; daily quota 1 fish; no release above 18°C; side-water fishing banned except Hagnesvassdraget. Subject to mid-season evaluation.
Kjærrafossen & falls — migration timing contextEnquiry
The falls and named pools — Kjærrafossen, Naugfossen and Hoggtveita — are the migration markers that explain when upper-river water comes good.
Permits & access
Permit required — see local rules.
- Fiskeravgift (national fee) PLUS local permit required for anadromous fishing
- Lower river (to Holmfoss) opens 15 May; upper river (Holmfoss–Hvittingfoss) opens 1 June
- Daily quota 1 fish
- Side-water fishing banned except Hagnesvassdraget
- Rules subject to mid-season evaluation and may be extended, restricted or stopped.
What's coming
Plan ahead
5-day outlook
Water here around 22°C. Nothing cooler within range — carry a thermometer.
Gallery · 2
Numedalslågen in the autumn Terrain map
Water quality (WFD)
- Ecology: Unknown
- Chemical: Unknown
Why this score · for Atlantic Salmon
- Temperature030% weight
- Flow9025% weight
- Clarity7520% weight
- Feeding Time9015% weight
- Pressure8510% weight
Directions
Seasons & zones
- Salmon15 May (mouth to Holmfoss); 1 June (Holmfoss to Hvittingfoss) → 8 August (mouth to Holmfoss); 24 August (Holmfoss to Hvittingfoss)
- TroutOpens Variable — typically June onward
Salmon: Open (2026) — Salmon fishing open in 2026 under Numedalslågen forvaltningslag management. Miljødirektoratet confirmed 2026 rule changes in April 2026. A mid-season evaluation in mid-July may extend, tighten or stop fishing depending on in-season returns; returns >50% below target halt fishing.
Sea trout: Open (2026) — Sea trout present and fishable under the same local permit and seasonal framework; confirm reach-specific rules locally.
Related guides
Booking & contacts