Water temperature for Atlantic Salmon
Ideal15°C est.ideal 10–16°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
Fair conditions based on river hydrology and migration patterns.
Likely species
Stoneflies
Caddisflies
Caddisflies- CapererMost likelyLower confidence#10–12 · AdultBig autumn sedge; fish dry at last light.
- Green SedgeAlso possibleLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- Large sedgesAlso possibleNearest relative#8–10 · AdultBig waked sedge in the last light and after dark.
- Net-spinning caddisAlso possibleLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
Gammarids
Hatch timeline · todayPeak at 12h
12h(now) — Heather Fly
Stage: Terrestrials on topApproach: Dry flyActivity: 47%
Also:Reed Smut29%
Peak emergence window4 food groups active
Peak activity at 12h — Heather Fly (Heather Fly, Peak emergence window)
Sub-surface · on the nymphunder the surface
Hatch predictions
Supporters see the full sub-surface read.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey(1)
Hatch predictions
Top prey shown — see all 3 as a supporter.
Start free trial14-day free trial. Cancel anytime.
Evidence
Survey-backed · regionalHigh confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Salmon runRun
1
2
2
2
2
2
2
1
March BrownHatch
2
3
2
CapererHatch
2
3
3
2
Heather FlyHatch
2
2
Autumn DunHatch
2
3
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Atlantic Salmon
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
The Shimna River flowing through autumn woodland in Tollymore Forest Park, County Down. Terrain map
The full read · show the working · for Atlantic Salmon · confidence 75%
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 temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Directions
Seasons & zones
- Salmon 1 March → 31 October
Sea trout: Variable seasonal (2026)
Related guides
Casting instructors near here
Booking & contacts
River Shimna
Water temperature for Atlantic Salmon
Ideal15°C est.ideal 10–16°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
Fair conditions based on river hydrology and migration patterns.
Likely species
Caddisflies
- CapererMost likelyLower confidence#10–12 · AdultBig autumn sedge; fish dry at last light.
- Green SedgeAlso possibleLower confidenceNearest relative#10–12–14–16 · NymphFree-living green caddis larva; fast stony riffles.
- Large sedgesAlso possibleNearest relative#8–10 · AdultBig waked sedge in the last light and after dark.
- Net-spinning caddisAlso possibleLower confidenceNearest relative#12–14–16 · PupaWidespread riffle net-spinner; evening emergence.
Hatch timeline · todayPeak at 12h
12h(now) — Heather Fly
Stage: Terrestrials on topApproach: Dry flyActivity: 47%
Also:Reed Smut29%
Peak emergence window4 food groups active
Peak activity at 12h — Heather Fly (Heather Fly, Peak emergence window)
Sub-surface · on the nymphunder the surface
Hatch predictions
Supporters see the full sub-surface read.
Start free trial14-day free trial. Cancel anytime.
Beyond the hatch · worth watchingambient prey(1)
Hatch predictions
Top prey shown — see all 3 as a supporter.
Start free trial14-day free trial. Cancel anytime.
Evidence
Survey-backed · regionalHigh confidence
Backed by regional invertebrate surveys; no sampling on this exact reach yet.
Through the year
0–3 scale · September highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Salmon runRun
1
2
2
2
2
2
2
1
March BrownHatch
2
3
2
CapererHatch
2
3
3
2
Heather FlyHatch
2
2
Autumn DunHatch
2
3
2
Numbers are intensity 0 (none) to 3 (peak) — a guide, not a guarantee.
Ranked for today
Fly box · Atlantic Salmon
What's coming
Plan ahead
5-day outlook
Other water nearby · 5
Gallery · 2
The Shimna River flowing through autumn woodland in Tollymore Forest Park, County Down. Terrain map
The full read · show the working · for Atlantic Salmon · confidence 75%
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 temperatureair-to-water estimateestimated
Level / flowon-river gaugeobserved
Directions
Seasons & zones
- Salmon 1 March → 31 October
Sea trout: Variable seasonal (2026)
Related guides
Casting instructors near here
Booking & contacts