Spate · Mixed · Co. Donegal / Foyle System (border), GB-NIR

River Finn

A wide, calm stretch of the River Finn near Clady bridge, flanked by autumn trees and low hills under a cloudy sky.

The Finn is the largest tributary of the Foyle system, rising in the Blue Stack Mountains of Donegal and flowing east to join the Mourne at Strabane.

Marginal · Atlantic Salmon
Cascade · 10-14
Marginallive now
Marginal — persistence required
River dropping into shape after a lift. A short window. Work the obvious lies and move on.
85% confidence
What moved it
  • Level0.57 mDropping after lift
  • Water temp18.1°C
  • ClarityClear
Today's fly
Cascade
Cascade10-14
Regional salmon default — river-specific evidence is thin.
Conditions on the water
Live gauge
Level
Steady
0.57 m
Dropping after lift
Water temp18.1°C
ClarityClear
Weather16°C
WindNW 16 km/h
Pressure1021 hPa
Rain · recent4.7 mm
Rain · ahead1.9 mm

Live readings only. Trends shown where the gauge supports them.

Water temperature for Atlantic Salmon
Warm — slow
18.1°Cideal 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 18.1°C — above the atlantic salmon 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 · Dun
    Duns are up; a sherry spinner fall may follow.
  • Anglers curse mayfliesAlso possibleLower confidence
    #20–22 · Spinner
    Go tiny: 20-22 spent spinner, single fly, long tippet.
Hatch timeline · todayPeak at 6am

Hatch predictions

Today's headline hatch shown — see all 6 active hatches hour by hour with Pro.

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Sub-surface · on the nymphunder the surface

Hatch predictions

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 2 with Pro.

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Through the year
0–3 scale · August highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Salmon runRun
1
2
2
2
2
2
1
Daddy Long LegsHatch
2
3
2
March BrownHatch
2
3
2
GrannomHatch
2
2
Large StoneflyHatch
2
3
2

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

Ranked for today
Atlantic Salmon fly box

Connemara/Mayo low water: a lightly-dressed shrimp on a floating line with sink tip, sized down from 8s in cold spring water to 12s and 14s as summer water warms and clears. Where the current runs faster, a slim tube or hairwing swung through tracks better than a shrimp.

What's coming
Plan ahead
5-day outlook
Cooler water nearby · 1
Water here at 18.1°C — the fishing's alive, but these are cooler if you'd rather rest the warm water.
River Mourne
26 km
~14°C
Brown trout · Salmon · Sea trout
Gallery · 2
  1. A wide, calm stretch of the River Finn near Clady bridge, flanked by autumn trees and low hills under a cloudy sky.
    gc366day317
  2. Terrain map of the venue
    Terrain map
About this water

The Finn is the largest tributary of the Foyle system, rising in the Blue Stack Mountains of Donegal and flowing east to join the Mourne at Strabane. A powerful spate river with excellent salmon and sea trout. The river has both Republic (upper) and Northern Ireland (lower) sections — the Loughs Agency manages the fishery across the border. Salmon run from March with grilse from June. Sea trout from May. One of the most productive salmon rivers in the Foyle system. Day permits from Loughs Agency. Atlantic salmon are managed under DAERA and Loughs Agency conservation byelaws, with mandatory catch-and-release on many waters; check current rules before fishing.

Hatches & food

No venue-specific hatch data yet; as a spate river of this basalt-and-peat country, expect flood-driven stonefly and terrestrial food to dominate over any steady upwing hatch — treat this as general guidance, not an observed hatch.

Sea trout here

Summer-autumn runs, seasonal patterns vary by region

  • Mixed
The full read · show the working · for Atlantic Salmon · confidence 85%
How the river scores — hydrology factors
Water heightMedium Ideal0.0
Recent riseNone0.0
Falling after liftNot Applicable0.0
Water temperatureCool To Moderate0.0
Time in seasonOpening Period0.0
ClarityClearing0.0
Hydrology base0.0
Legal gate: Unknown Check Local Rules
Can you trust it?
Water temperaturelive gauge readinggauge
Level / flowon-river gaugeobserved
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Salmon 1 March → 15 September

Sea trout: Variable seasonal (2026)

Related guides
Atlantic Salmonsalmon tacticsIrish Salmon Rivers Guidefive great salmon fisheriesConnemaraIrish fishing
Casting instructors near here
Booking & contacts