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United Kingdom / Gwynedd / River Afon Arddu

Bite forecast: River Afon Arddu

  • length 8 km
Loading map…

Best fishing days for the next week

  1. TuesdaySeptember 8weather-based forecast
    56/100medium activity

    Partly cloudy: 11–16 °C

  2. MondaySeptember 7weather-based forecast
    55/100medium activity

    Cloudy: 14–17 °C

  3. SundaySeptember 6weather-based forecast
    54/100medium activity

    Clear: 15–23 °C

River Afon Arddu (Gwynedd) — a popular fishing spot. About 8 km long. A smart bite calendar — moon phase, atmospheric pressure, and weather combined into an hourly fish-activity forecast for the coming days.

Loading map…

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?
DaceGraylingPikeBarbelEuropean eelRuffeWhitefishZanderAtlantic salmonBreamCarpPerchRainbow troutBrown troutWels catfishIdeRoachBleakChubCrucian carpRuddWhite breamTench

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. 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: salmon spoon or salmon fly.

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.

How this forecast is calculated

Why this forecast

The computed water temperature is around 16 °C — warmer than the 4–14 °C comfort range for Atlantic salmon: in the heat it drops deeper and feeds less often.

Computed water temperature by month; the green band is the 4–14 °C comfort rangecomfort 4–14 °C16 °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 9 hPa over the day — the bite usually settles down after a rise.

Pressure through the day, 9 hPa change
00:00 · 101023:00 · 1019 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
+17°

Cloudy · feels like +13°

Low / high
+14°…+18°
Precipitation
0.0 mm
Wind
18 mph W
Cloud cover
100%
Humidity
64%
Pressure
1013 hPa
00:00+16°3.8 mm6 mphwest wind, 6 mph98%100%
01:00+16°9.0 mm2 mphnorthwest wind, 2 mph98%100%
02:00+16°8.0 mm12 mphwest wind, 12 mph98%100%
03:00+16°1.5 mm8 mphwest wind, 8 mph95%100%
04:00+16°2.0 mm10 mphwest wind, 10 mph97%100%
05:00+15°1.6 mm8 mphwest wind, 8 mph96%100%
06:00+15°0.5 mm11 mphwest wind, 11 mph96%100%
07:00+15°—12 mphwest wind, 12 mph93%100%
08:00+16°—14 mphwest wind, 14 mph90%100%
09:00+16°—15 mphwest wind, 15 mph78%100%
10:00+16°—17 mphwest wind, 17 mph75%100%
11:00+17°—18 mphwest wind, 18 mph67%100%
12:00+17°—18 mphwest wind, 18 mph64%100%
13:00+18°—18 mphwest wind, 18 mph61%100%
14:00+18°—18 mphwest wind, 18 mph60%100%
15:00+18°—17 mphwest wind, 17 mph62%89%
16:00+18°—18 mphwest wind, 18 mph62%76%
17:00+18°—17 mphwest wind, 17 mph62%98%
18:00+17°0.1 mm16 mphwest wind, 16 mph70%100%
19:00+16°0.6 mm12 mphwest wind, 12 mph78%47%
20:00+15°0.7 mm9 mphwest wind, 9 mph89%53%
21:00+15°—11 mphwest wind, 11 mph82%77%
22:00+14°—12 mphwest wind, 12 mph83%45%
23:00+14°—12 mphwest wind, 12 mph82%78%
+18°+16°+14°
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
06:32
Sunset
19:58
Day length
13 h 26 min
Sunshine hours
7 h
UV index
3
moderate
Moon
Last quarter
Moonrise
22:36
Moonset
16:13

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 windowFriday, September 4
Feeding windows on the day scale, local time0:0012:0024:00
Major periodsMinor periods
  • Major05:55–07:55Moon overhead
  • Minor15:43–16:43Moonset
  • Major18:26–20:26Moon underfoot
  • Minor22:06–23:06Moonrise

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?

Nearby rivers

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  • Seiont3 mi
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Nearby water bodies

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  • ReservoirLlyn Peris1 mi
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  • LakeLlyn Nadroedd3 mi
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