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  • Forecast
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Ireland / County Donegal / Swilly River

Bite forecast: Swilly River

  • length 4 km
  • Flows into Atlantic Ocean
Loading map…

Best fishing days for the next week

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

    Clear: 11–15 °C

Swilly River (County Donegal) — one of the area's fishing spots. About 4 km long. Flows into Atlantic Ocean. Close by — Letterkenny, Ramelton and Raphoe. Here you'll find a bite prediction — when fish are active and which hours give the best chances, adjusted for weather and pressure.

Nearby rivers

  • Corkey2 mi
  • Leannan River6 mi
  • Deele7 mi
  • Swilly9 mi

Nearby water bodies

  • LakeMagheradrumman Lough7 mi
  • LakeDifflin Lake7 mi
  • LakeClonkillybeg Lough7 mi
  • LakeCloncarney Lough7 mi
  • LakeGannon's Lough7 mi
  • LakeCarn Lough7 mi
  • LakeLough Fern7 mi
  • LakeThorn Lough8 mi
  • LakeThe Bog Lough8 mi
  • LakeIrvine's Lough8 mi
Loading map…
MondaySeptember 7weather-based forecast
59/100medium activity

Partly cloudy: 12–15 °C

  • ThursdaySeptember 10weather-based forecast
    59/100medium activity

    Drizzle: 11–13 °C

  • Nearby towns

    • Letterkenny2 mi
    • Ramelton5 mi
    • Raphoe6 mi

    Bite calendar

    Friday, September 4

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

    Atlantic salmon

    5/10 · Fair

    Hourly activity

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

    The bite is moderate — fish feed in short bursts. Pressure is dropping — this usually boosts the bite.

    Peak bite hours

    Best time — 06:00–08:00 (dawn bite) and 20:00–22:00 (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: salmon spoon or salmon fly.

    Gear

    No special gear needed — seasonal clothing will do. Rain is expected — don't forget a rain jacket or a waterproof shell.

    Summary

    An average day — best chances during peak windows.

    How this forecast is calculated

    Why this forecast

    The computed water temperature is around 13 °C — inside the 4–14 °C comfort range for Atlantic salmon, so baseline activity is high.

    Computed water temperature by month; the green band is the 4–14 °C comfort rangecomfort 4–14 °C13 °C
    JFMAMJJASOND

    Atlantic salmon 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 Atlantic salmon feeds0:0012:0024:00

    Pressure is rising 11 hPa over the day — the bite usually settles down after a rise.

    Pressure through the day, 11 hPa change
    00:00 · 100623:00 · 1017 hPa

    One more input — the moon's feeding windows: within their hours the score sits higher than across the rest of the day. The window times are in the “Solunar feeding periods” card below.

    Feeding windows on the day scale0:0012:0024:00

    September is an active season for Atlantic salmon here.

    JFMAMJJASOND

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

    4 SepFriday, September 4
    +14°

    Partly cloudy · feels like +10°

    Low / high
    +12°…+15°
    Precipitation
    0.0 mm
    Wind
    17 mph W
    Cloud cover
    71%
    Humidity
    76%
    Pressure
    1009 hPa
    00:00+13°—11 mphsouthwest wind, 11 mph91%100%
    01:00+13°1.1 mm13 mphsouthwest wind, 13 mph92%100%
    02:00+13°—13 mphsouthwest wind, 13 mph84%100%
    03:00+13°0.2 mm14 mphsouthwest wind, 14 mph86%100%
    04:00+13°—15 mphsouthwest wind, 15 mph83%100%
    05:00+12°0.1 mm17 mphsouthwest wind, 17 mph85%100%
    06:00+13°—18 mphwest wind, 18 mph82%88%
    07:00+14°0.1 mm19 mphwest wind, 19 mph82%98%
    08:00+13°—17 mphwest wind, 17 mph84%66%
    09:00+13°0.1 mm16 mphwest wind, 16 mph80%100%
    10:00+14°—19 mphwest wind, 19 mph77%72%
    11:00+14°—19 mphwest wind, 19 mph73%69%
    12:00+14°—17 mphwest wind, 17 mph76%71%
    13:00+15°—21 mphwest wind, 21 mph70%64%
    14:00+13°0.1 mm19 mphwest wind, 19 mph84%100%
    15:00+15°—21 mphwest wind, 21 mph73%45%
    16:00+14°0.5 mm18 mphwest wind, 18 mph89%88%
    17:00+14°0.1 mm18 mphwest wind, 18 mph80%89%
    18:00+14°—18 mphwest wind, 18 mph77%30%
    19:00+13°—15 mphwest wind, 15 mph79%67%
    20:00+13°—16 mphwest wind, 16 mph78%41%
    21:00+13°—16 mphwest wind, 16 mph77%57%
    22:00+13°—14 mphwest wind, 14 mph77%100%
    23:00+13°—13 mphwest wind, 13 mph78%80%
    +15°+14°+12°
    Weather throughout the day
    0:006:0012:0018:0023:00

    Sun and moon

    Friday, September 4
    The day: daylight and the hours the moon is above the horizon. Local time0:0012:0024:00
    DaylightMoon above the horizon
    Sunrise
    06:44
    Sunset
    20:17
    Day length
    13 h 33 min
    Sunshine hours
    7 h 12 min
    UV index
    3
    moderate
    Moon
    Last quarter
    Moonrise
    22:34
    Moonset
    16:49

    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

    +14% in the windowFriday, September 4
    Feeding windows on the day scale, local time0:0012:0024:00
    Major periodsMinor periods
    • Major06:12–08:12Moon overhead
    • Minor16:19–17:19Moonset
    • Major18:43–20:43Moon underfoot
    • Minor22:04–23:04Moonrise

    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?