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Trearddur Bay (Holy Island) Surf Forecast
/ Wales – Anglesy (10 surf breaks) /
Surf Forecasts:
Trearddur Bay (Holy Island) surfForecast / Wales – Anglesy / UK
48hr Weather and Surf, issued 11 am Wednesday 21 Jan 2026 GMTForecast update in hr min s Forecast update imminent
Trearddur Bay (Holy Island) surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Trearddur Bay (Holy Island) sea temperature is
8.4° C
(Which is normal for this time of year)How big are the waves at Trearddur Bay (Holy Island) today?
The current surf forecast for Trearddur Bay (Holy Island) at 7PM is: 1.1m 8s primary swell from a South-southwest direction and 1.1m 5s secondary swell from a Southeast direction (forecast issued at 11:00am January 21). An open ocean swell of 0.4m 6s is not directed at the surf break. The wind direction is predicted to be cross-shore.
| Time (GMT) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (21 Jan) | 3ft (0.9m) | 9s |
| Afternoon (21 Jan) | 3.5ft (1.1m) | 8s |
| Evening (21 Jan) | 5ft (1.5m) | 8s |
Table - waves today at Trearddur Bay (Holy Island). (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Wednesday 21 | Thursday 22 | Friday 23 | Saturday 24 | |||||||||||||||||||||
| 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 9 | 8 | 8 | 8 | 8 | 8 | 6 | 10 | 10 | 10 | 10 | 9 | 15 | 5 | 9 | 9 | 6 | 18 | 17 | 17 | 13 | 13 | 12 | 12 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 111 | 169 | 146 | 164 | 298 | 347 | 130 | 480 | 373 | 307 | 214 | 161 | 70 | 51 | 38 | 38 | 57 | 263 | 708 | 2378 | 1383 | 1548 | 1117 | 735 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross- off | cross- off | cross- off | cross | cross- off | cross | cross | cross- off | cross- off | cross | cross- off | cross- off | cross- on | cross | cross- off | cross- off | cross- off | cross- off | cross | cross- off | cross- off | cross- off | cross- off | cross- off |
High Tide / height (m) | 11:49AM 5.65 | 12:12AM 5.25 | 12:24PM 5.64 | 12:47AM 5.21 | 1:01PM 5.59 | 1:26AM 5.14 | ||||||||||||||||||
Low Tide / height (m) | 6:00PM 0.94 | 6:11AM 1.13 | 6:36PM 0.93 | 6:48AM 1.17 | 7:15PM 0.98 | |||||||||||||||||||
Wednesday 21 | Thursday 22 | Friday 23 | Saturday 24 | |||||||||||||||||||||
| Sunrise | 8:18 | - | - | - | - | - | - | - | 8:18 | - | - | - | - | - | - | - | 8:15 | - | - | - | - | - | - | - |
| Sunset | - | - | 4:39 | - | - | - | - | - | - | - | 4:42 | - | - | - | - | - | - | - | 4:43 | - | - | - | - | - |
 |  | |  | |  |  | | |  | | | |  | | | | |  | |  | | | | |
Rain (mm) | - | 2 | - | 1 | 1 | 1 | - | - | - | - | - | 1 | 1 | - | - | - | - | 1 | - | - | - | - | - | - |
| Temp. °C | 7 | 8 | 10 | 11 | 10 | 10 | 10 | 9 | 9 | 9 | 9 | 9 | 7 | 7 | 7 | 7 | 7 | 6 | 8 | 7 | 6 | 6 | 7 | 7 |
| Feels °C (?) | -1 | -1 | 4 | 3 | 3 | 3 | 5 | 5 | 4 | 4 | 4 | 3 | -1 | 1 | 1 | -2 | -2 | -3 | -1 | -2 | -4 | -5 | -4 | -5 |
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