Stillwater · Ordovician Volcanics · Wales / Llŷn Peninsula (Eifionydd, Dwyfor catchment)

Llyn Cwmystradllyn

Still blue water of Llyn Cwmystradllyn with a submerged boundary fence, green hills, and an old slate quarry scar on the far hillside under a cloudy sky.
Fair · Trout
Minkie · 6-10
Fairlive now
Good drifting conditions on Llyn Cwmystradllyn
Good wave on — drift country. A useful wave. Work the productive shore.
55% confidence

Llyn Cwmystradllyn is often best in spring through autumn.

What moved it
  • WindN 16 km/hGentle breeze · Gusts to 35 km/h
Today's fly
Minkie
Minkie6-10
Retrieve, sub-surface
Conditions on the water
Estimate
Wind
Gentle breeze · Gusts to 35 km/h
N 16 km/h
N
N
from the north
Wave20 cm ripple
Water temp8.8°C
Air temp11°C
CloudOvercast
Pressure1017 hPa
Rain · recent0.0 mm

No gauge on this water — readings are regional estimates from weather, not a live gauge.

Head to
Wind driftN wind
Southern end

A northerly has held for 6 hours, running warmer than the water (11°C air against 9°C water). Expect fish at the southern end — the bank it is blowing into — where the drift piles food, colour and warmth together. This reads the upper water, though — a bottom bait at range feels it far less than a floater or a fish in the margins. Treat it as a tiebreaker between good swims rather than an override — features and angling pressure usually count for more.

How to fish it · for Trout
When
The buzzer is on. The ripple is helpful — fish should move onto the feed and a slow-drifted team or single wet will cover water well.
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

Keep an eye on changing conditions — wind shifts and cloud breaks can trigger short feeding spells.

Bank

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

Sub-surface · on the nymphunder the surface

Hatch predictions

Supporters see the full sub-surface read.

Start free trial

14-day free trial. Cancel anytime.

Beyond the hatch · worth watchingambient prey(1)

Hatch predictions

Top prey shown — see all 5 as a supporter.

Start free trial

14-day free trial. Cancel anytime.

Through the year
0–3 scale · October highlighted
J
F
M
A
M
J
J
A
S
O
N
D
Heather FlyHatch
2
2
Daddy Long LegsHatch
2
3
2
Claret DunHatch
2
3
2
Murrough (Great Red Sedge)Hatch
2
3
2

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

Ranked for today
Fly box · Trout
Bays & launches · 1
Day ticket via Pwllheli & District AAAccess varies
The association's headline reservoir — stocked rainbows and blue trout over a base of wild browns, in the quieter Dwyfor catchment west of Snowdonia proper.
Visit official site ↗
What's coming
Plan ahead
5-day outlook
Condition match
59%
Cloud50%
Wind65%
Temp60%

A reasonable day here, though cloud isn't quite in the sweet spot.

Other water nearby · 5
Gallery · 2
  1. Still blue water of Llyn Cwmystradllyn with a submerged boundary fence, green hills, and an old slate quarry scar on the far hillside under a cloudy sky.
    Llyn Cwmystradllyn
  2. Terrain map of the venue
    Terrain map
Why this score
  • Buzzer is in its seasonal window, boosting the chance of targeted feeding.
Related guides
Casting instructors near here
Booking & contacts
Boards & regulators