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Surf Forecasts:
Trearddur Bay (Holy Island) surfForecast / Wales – Anglesy / UK
48hr Weather and Surf, issued 11 pm Thursday 11 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
11.1° C
(Which is slightly warmer than usual)How big are the waves at Trearddur Bay (Holy Island) today?
The current surf forecast for Trearddur Bay (Holy Island) at 7AM is: 1.2m 9s primary swell from a South-southwest direction and 0.6m 13s secondary swell from a Southwest direction (forecast issued at 11:00pm December 11). The wind direction is predicted to be glassy and the swell rating is 2.
| Time (GMT) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (12 Dec) | 3.5ft (1.0m) | 9s |
| Afternoon (12 Dec) | 3.5ft (1.1m) | 9s |
| Evening (12 Dec) | 2.5ft (0.8m) | 9s |
Table - waves today at Trearddur Bay (Holy Island). (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Friday 12 | Saturday 13 | Sunday 14 | ||||||||||||||||||||||
| 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 | 9 AM | 12 PM | 3 PM | 6 PM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |  |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 8 | 8 | 8 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 9 | 5 | 5 | 6 | 7 | 8 | 8 | 8 | 8 | 9 | 9 | 8 | 8 | 8 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 890 | 559 | 307 | 249 | 176 | 190 | 211 | 294 | 99 | 99 | 230 | 82 | 154 | 396 | 855 | 1176 | 1334 | 1510 | 1799 | 2129 | 2129 | 1786 | 1745 | 1645 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | cross- on | on | cross | glass | cross- on | on | on | on | cross- on | on | on | on | on | on | on | on | on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on | cross- on |
High Tide / height (m) | 3:54AM 4.59 | 4:10PM 4.88 | 5:01AM 4.48 | 5:19PM 4.75 | 6:08AM 4.50 | |||||||||||||||||||
Low Tide / height (m) | 9:36PM 1.64 | 9:49AM 2.15 | 10:42PM 1.81 | 10:58AM 2.25 | 11:48PM 1.88 | 12:07PM 2.24 | ||||||||||||||||||
Friday 12 | Saturday 13 | Sunday 14 | ||||||||||||||||||||||
| Sunrise | - | - | - | - | 8:22 | - | - | - | - | - | - | - | 8:23 | - | - | - | - | - | - | - | 8:25 | - | - | - |
| Sunset | - | - | - | - | - | - | 4:00 | - | - | - | - | - | - | - | 4:00 | - | - | - | - | - | - | - | 4:00 | - |
 |  | | |  | | |  |  |  | | |  | | | | | | | |  | | | | |
Rain (mm) | - | 4 | 3 | - | - | - | - | - | 1 | - | - | - | - | - | - | 1 | 2 | 1 | - | - | 1 | 1 | 2 | 1 |
| Temp. °C | 12 | 9 | 9 | 9 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 10 | 11 | 11 | 11 | 11 | 11 | 10 | 10 |
| Feels °C (?) | 3 | 5 | 5 | 7 | 5 | 3 | 3 | 3 | 5 | 4 | 3 | 3 | 1 | -1 | -1 | -1 | -1 | 0 | 0 | 0 | 0 | -1 | -1 | -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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