Upland Natural Lake · Slate · Gwynedd / Snowdonia

Llynnau Mymbyr

Panoramic view across the twin lakes of Llynnau Mymbyr toward Moel Siabod and Snowdon in Eryri National Park, Wales
Fair · Trout
Diawl Bach · 12-14
A respectable few hours, if you choose your moments
Good wave on — drift country. A useful wave. Work the productive shore.
48% confidence
limited data
What moved it
  • WindNW 12 km/hLight breeze
Today's fly
Diawl Bach
Diawl Bach12-14
Washing-line, sub-surface
Conditions on the water
Live gauge
Wind
Light breeze
NW 12 km/h
N
NW
from the north-west
Wave20 cm ripple
Water temp—
Air temp19°C
CloudOvercast
Pressure1020 hPa
Rain · recent0.0 mm

Some readings unavailable — check directly before fishing.

How to fish it · for Trout
When
May to September
Where
Set up a broadside drift and cover the water systematically. Work a bushy searching pattern on the bob and drop a contrasting nymph on the point.
The plan
Plan A

Set up a broadside drift and cover the water systematically. Work a bushy searching pattern on the bob and drop a contrasting nymph on the point.

Plan B

If the main plan is not working, switch to a smaller, more imitative pattern fished slower and deeper. A change of drift angle can also make a difference.

Watch for

Evening tends to be the best period in summer — stay late if you can for a sedge or spinner fall.

Bank

Bank-only venue. Fish from accessible margins, points, weed edges, and inflows.

Sub-surface · on the nymphunder the surface

Hatch predictions

Top nymph shown — see all 2 guilds with Pro.

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Beyond the hatch · worth watchingambient prey

Hatch predictions

Top prey shown — see all 3 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
Trout seasonSeason
1
2
2
2
2
2
1
Daddy Long LegsHatch
2
3
2
Murrough (Great Red Sedge)Hatch
2
3
2
Black MidgeHatch
2
3
3
3
3
3
3
3
3
3
3
2
Lake OliveHatch
1
2
2
2
2
2
1

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

Ranked for today
Trout fly box
What's coming
Plan ahead
5-day outlook
Condition match
91%
Cloud70%
Wind100%
Temp100%

Conditions are ideal for Llynnau Mymbyr — wind, cloud and temperature all line up.

Other water nearby · 5
Llyn Diwaunedd
3.0 km
Brown trout · Arctic char
Llyn Bochlwyd
4.0 km
Brown trout
Llyn Idwal
5.0 km
Brown trout
Llyn Ogwen
5.0 km
Brown trout · Rainbow trout
Ffynnon Lloer
6.0 km
Brown trout
Gallery · 2
  1. Panoramic view across the twin lakes of Llynnau Mymbyr toward Moel Siabod and Snowdon in Eryri National Park, Wales
    Llynnau Mymbyr looking toward Moel Siabod and Snowdon, Eryri
  2. Terrain map of the venue
    Terrain map
Why this score
  • Wind conditions (ripple) closely match what this water fishes best in.
  • Temperature (moderate) is in the sweet spot for summer fishing.
  • Daddy Longlegs are in their seasonal window, boosting the chance of targeted feeding.
Directions
Apple MapsGoogle Maps
Seasons & zones
  • Trout 3 March → 30 September
Related guides
Scotland Playbookloch & river fishingThermal Layers & Troutreading depth and temperatureEuro Nymphingsubsurface methods
Casting instructors near here
Booking & contacts
Clubs & associations