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Surf Forecasts:
Trearddur Bay (Holy Island) surfForecast / Wales – Anglesy / UK
48hr Weather and Surf, issued 5 am Sunday 21 Dec 2025 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
10.9° C
(Which is 1.1°C warmer than 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 1PM is: 1.0m 9s primary swell from a South-southwest direction and 0.4m 15s secondary swell from a Southwest direction (forecast issued at 05:00am December 21). An open ocean swell of 0.1m 5s is not directed at the surf break. The wind direction is predicted to be cross-offshore.
| Time (GMT) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (21 Dec) | 4.5ft (1.3m) | 10s |
| Afternoon (21 Dec) | 3ft (0.9m) | 9s |
| Evening (21 Dec) | 2.5ft (0.7m) | 8s |
Table - waves today at Trearddur Bay (Holy Island). (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Sunday 21 | Monday 22 | Tuesday 23 | Wed 24 | |||||||||||||||||||||
| 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 | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |    |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 10 | 10 | 10 | 9 | 9 | 9 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 7 | 7 | 7 | 6 | 6 | 6 | 8 | 8 | 8 | 8 | 8 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 942 | 529 | 305 | 199 | 121 | 94 | 70 | 45 | 45 | 32 | 25 | 15 | 14 | 14 | 13 | 9 | 4 | 4 | 4 | 5 | 2 | 2 | 2 | 1 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross | cross | cross- off | cross- off | cross- off | off | off | off | cross- off | cross- off | cross- off | cross- off | glass | off | off | off | off | off | off | off | off | off | off | off |
High Tide / height (m) | 10:58AM 5.44 | 11:19PM 5.10 | 11:34AM 5.46 | 11:56PM 5.06 | 12:09PM 5.43 | |||||||||||||||||||
Low Tide / height (m) | 4:45AM 1.48 | 5:08PM 1.39 | 5:19AM 1.49 | 5:44PM 1.37 | 5:55AM 1.53 | 6:21PM 1.37 | ||||||||||||||||||
Sunday 21 | Monday 22 | Tuesday 23 | Wed 24 | |||||||||||||||||||||
| Sunrise | - | - | 8:30 | - | - | - | - | - | - | - | 8:30 | - | - | - | - | - | - | - | 8:30 | - | - | - | - | - |
| Sunset | - | - | - | - | 4:00 | - | - | - | - | - | - | - | 4:01 | - | - | - | - | - | - | - | 4:01 | - | - | - |
 | |  | | | |  | | |  |  | | |  | | | | |  | | | | | | |
Rain (mm) | - | - | - | - | - | - | 1 | 1 | 1 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| Temp. °C | 10 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 10 | 10 | 10 | 11 | 10 | 10 | 10 | 9 | 8 | 8 | 7 | 7 | 7 | 7 | 7 |
| Feels °C (?) | 3 | 4 | 5 | 5 | 3 | 3 | 3 | 2 | 3 | 6 | 7 | 8 | 10 | 7 | 8 | 7 | 5 | 4 | 2 | 1 | 1 | 1 | 2 | 2 |
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
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