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United Kingdom / Gwynedd / Brown trout

Brown trout bite in Gwynedd

Recorded 5 catches of Brown trout in Gwynedd. Most active — August–September. A day-by-day bite calendar for Brown trout.

Brown trout bite forecast in Gwynedd today

Best fishing days for the next week

  1. WednesdaySeptember 9weather-based forecast
    60/100high activity

    Partly cloudy: 9–15 °C

    Best fishing time: 06:00–09:00

  2. SundaySeptember 6weather-based forecast
    56/100medium activity

    Cloudy: 16–20 °C

    Best fishing time: 06:00–09:00

  3. ThursdaySeptember 3weather-based forecast
    54/100medium activity

    Cloudy: 16–19 °C

    Best fishing time: 05:00–08:00

How to catch Brown trout

Tackle, baits, spots and seasons — a full guide to catching Brown trout.

Read the guide →

Map of waters and catches

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Where it's caught

  • Llyn Mawr Gamallt2 catches
  • Llyn Cwellyn1 catch
  • Llyn Bach Gamallt1 catch
  • River Dwyfor1 catch

Catches

  • Brown trout
    Llyn Cwellyn
    17 °C16 mph
    Sep 17, 2021, 1:24 PM
  • Brown trout
    Llyn Bach Gamallt
17 °C
7 mph
Sep 05, 2021, 4:32 PM
  • Brown trout
    Llyn Mawr Gamallt
    17 °C7 mph
    Sep 05, 2021, 2:53 PM
  • Brown trout
    Llyn Mawr Gamallt
    17 °C7 mph
    Sep 05, 2021, 2:45 PM
  • Brown trout
    River Dwyfor
    19 °C18 mph
    Aug 21, 2015, 11:13 AM
  • Brown trout bite calendar

    Thursday, September 3

    Aug 31 – Sep 6
    Mon
    Tue
    Wed
    Thu
    Fri
    Sat
    Sun
    Bite activity:highmediumlowslow
    Based on:weatherseasonal
    What is a bite calendar?

    Hourly activity

    0:006:0012:0018:0023:00
    Bite activity:highmediumlow

    The bite is moderate — fish feed in short bursts. A thunderstorm is possible: activity rises before the front and drops after.

    Peak bite hours

    Best time — 06:00–08:00 (dawn bite) and 20:00–21:00 (dusk bite).

    Tactics

    Work the cover — snags, weed edges, hole entrances; retrieve the lure with pauses.

    Lures

    The water's turning murky — go with bright, noisy lures: spinner or small crankbait.

    Gear

    No special gear needed — seasonal clothing will do. A thunderstorm is possible — bring a rain jacket, and pack up at the first rumble of thunder.

    Summary

    An average day — best chances during peak windows.

    Why this forecast

    The computed water temperature is around 16 °C — inside the 6–17 °C comfort range for Brown trout, so baseline activity is high.

    Computed water temperature by month; the green band is the 6–17 °C comfort rangecomfort 6–17 °C16 °C
    JFMAMJJASOND

    Brown trout works the twilight: the peaks are pinned to sunrise and sunset — their times are in the sun-and-moon card above.

    The day: daylight hours and when Brown trout feeds0:0012:0024:00

    Pressure is dropping 2 hPa over the day — fish are usually more active ahead of a weather change.

    Pressure through the day, 2 hPa change
    00:00 · 101423:00 · 1012 hPa

    September is an average month for Brown trout here.

    JFMAMJJASOND

    These are the same values the bite curve above was computed from. How the forecast works

    3 SepThursday, September 3
    +19°

    Cloudy · feels like +18°

    Low / high
    +16°…+19°
    Precipitation
    0.0 mm
    Wind
    15 mph SW
    Cloud cover
    100%
    Humidity
    83%
    Pressure
    1016 hPa
    00:00+18°—16 mphwest wind, 16 mph96%95%
    01:00+18°—14 mphwest wind, 14 mph95%63%
    02:00+17°—13 mphwest wind, 13 mph93%100%
    03:00+17°—11 mphwest wind, 11 mph91%95%
    04:00+17°—13 mphwest wind, 13 mph91%23%
    05:00+17°—14 mphwest wind, 14 mph88%100%
    06:00+16°—12 mphwest wind, 12 mph92%100%
    07:00+16°—11 mphwest wind, 11 mph89%100%
    08:00+17°—12 mphwest wind, 12 mph86%100%
    09:00+18°—13 mphwest wind, 13 mph84%100%
    10:00+18°—15 mphsouthwest wind, 15 mph81%100%
    11:00+19°—15 mphsouthwest wind, 15 mph84%100%
    12:00+19°—15 mphsouthwest wind, 15 mph83%100%
    13:00+19°—17 mphsouthwest wind, 17 mph86%100%
    14:00+19°—19 mphsouthwest wind, 19 mph87%100%
    15:00+19°—20 mphsouthwest wind, 20 mph87%100%
    16:00+19°—20 mphsouthwest wind, 20 mph86%100%
    17:00+18°—22 mphsouthwest wind, 22 mph84%100%
    18:00+18°—22 mphsouthwest wind, 22 mph82%100%
    19:00+18°—22 mphsouthwest wind, 22 mph84%100%
    20:00+18°—20 mphsouthwest wind, 20 mph85%100%
    21:00+18°0.3 mm20 mphsouthwest wind, 20 mph87%100%
    22:00+17°2.1 mm18 mphsouthwest wind, 18 mph96%100%
    23:00+16°2.9 mm15 mphsouthwest wind, 15 mph94%100%
    +19°+18°+16°
    Weather throughout the day
    0:006:0012:0018:0023:00

    Sun and moon

    Thursday, September 3
    The day: daylight and the hours the moon is above the horizon. Local time0:0012:0024:00
    DaylightMoon above the horizon
    Sunrise
    06:30
    Sunset
    20:01
    Day length
    13 h 31 min
    Sunshine hours
    3 h 24 min
    UV index
    3
    moderate
    Moon
    Last quarter
    Moonrise
    21:52
    Moonset
    14:53

    The day is 4 min shorter than yesterday.

    Sunshine hours count direct sun only — cloud cover cuts it, so it is shorter than daylight.

    Solunar feeding periods

    +15% in the windowThursday, September 3
    Feeding windows on the day scale, local time0:0012:0024:00
    Major periodsMinor periods
    • Major04:56–06:56Moon overhead
    • Minor14:23–15:23Moonset
    • Major17:26–19:26Moon underfoot
    • Minor21:22–22:22Moonrise

    The windows are set by the moon's transit and rise, and the forecast above already accounts for them: within these hours the bite score sits higher than across the rest of the day, while the day's overall level still comes from the catch-calibrated model.

    What are solunar periods?