
Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 10 Nov 2026:
- Best quality surf: Wednesday 18 Nov, 3AM (local time) - 13ft (4.0m), 9s period, SW swell with cross-onshore winds.
- Most powerful swell: Wednesday 18 Nov, 9AM (local time) - 13ft (4.0m), 15s period, SW swell with 6,872 kJ wave energy.
- Next surfable swell (1★+): Tuesday 10 Nov, 3PM (local time) - 2.5ft (0.8m), 12s period with SW swell.
Best Forecast Surf Conditions for Trearddur Bay (Holy Island) this week:
The surf forecast for Trearddur Bay (Holy Island) over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Tuesday (Nov 10) at 3PM. The primary swell is predicted to be 0.8m and 12s period with a secondary swell of 0.2m and 4s. The wind is predicted to be offshore as the swell arrives.
The most powerful waves expected at Trearddur Bay (Holy Island) in the next 16 days are 4.0m 15s and forecast to arrive on Wednesday (Nov 18) at 9AM. Winds are predicted to be cross-onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.3m 5s period and expected on Monday (Nov 16) at 12AM.
| Wave Type | Time (GMT) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 3PM (Tue 10th Nov) | 2.5ft (0.8m) 12s |
| Best Surf | 3AM (Wed 18th Nov) | 13ft (4.0m) 9s |
| Most Powerful | 9AM (Wed 18th Nov) | 13ft (4.0m) 15s |
Table - best surf conditions forecast for Trearddur Bay (Holy Island) over the next 16 days.
Short Range ForecastMostly dry. Mild temperatures (max 9°C on Tue morning, min 7°C on Tue morning). Winds increasing (light winds from the ESE on Tue morning, fresh winds from the NNE by Thu morning). | Days 4-6 Weather SummaryLight rain (total 5mm), mostly falling on Sun night. Very mild (max 12°C on Sun night, min 7°C on Sat night). Winds increasing (calm on Fri afternoon, fresh winds from the SE by Sun night). | ||||||||||||||||||||
Tuesday 10 | Wednesday 11 | Thursday 12 | Friday 13 | Saturday 14 | Sunday 15 | Monday 16 | |||||||||||||||
AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | |
Swell Height Map | |||||||||||||||||||||
Wave Height (m) Direction Period (s) | SW 11 | SW 12 | SW 13 | SW 12 | SW 12 | SW 11 | SSW 10 | SSW 10 | SW 10 | SW 9 | SW 9 | SW 12 | SW 11 | SW 10 | SSW 5 | S 5 | SSW 6 | SSW 6 | SSW 9 | SW 10 | SW 10 |
Wave Graph | |||||||||||||||||||||
130 | 161 | 336 | 248 | 212 | 96 | 71 | 67 | 47 | 21 | 21 | 21 | 30 | 27 | 49 | 71 | 50 | 36 | 67 | 142 | 74 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | off | cross-off | off | off | cross-off | off | off | cross-off | cross-off | cross-off | cross-on | cross-on | cross-on | cross-on | cross | cross-on | cross-off | cross-on | cross | cross-on |
High Tide | 10:33AM5.50m | 10:50PM5.38m | 11:06AM5.49m | 11:25PM5.26m | 11:40AM5.42m | 00:01AM5.09m | 12:16PM5.30m | 00:38AM4.90m | 12:54PM5.13m | 1:21AM4.68m | 1:38PM4.95m | 2:11AM4.46m | 2:29PM4.76m | ||||||||
Low Tide | 4:39PM1.18m | 4:56AM1.24m | 5:15PM1.27m | 5:30AM1.40m | 5:51PM1.41m | 6:05AM1.61m | 6:29PM1.59m | 6:42AM1.85m | 7:10PM1.79m | 7:23AM2.09m | 7:57PM1.99m | 8:12AM2.32m | 8:53PM2.13m | ||||||||
7:31 | — | — | 7:33 | — | — | 7:35 | — | — | 7:37 | — | — | 7:39 | — | — | 7:41 | — | — | 7:43 | — | — | |
— | 4:30 | — | — | 4:29 | — | — | 4:27 | — | — | 4:25 | — | — | 4:23 | — | — | 4:22 | — | — | 4:21 | — | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 5 | 2 | 1 | — |
Temp °C | 9 | 9 | 9 | 9 | 9 | 9 | 8 | 8 | 8 | 8 | 9 | 8 | 8 | 8 | 8 | 8 | 8 | 12 | 14 | 12 | 11 |
Feels °C | 6 | 6 | 3 | 2 | 3 | 3 | 0 | 0 | 2 | 2 | 6 | 5 | 2 | 3 | 2 | 2 | 2 | 6 | 10 | 7 | 5 |
Swell 1 Height (m) Direction Period (s) | SW 11 | SW 12 | SW 13 | SW 12 | SW 12 | SW 11 | SSW 10 | SSW 10 | SW 10 | SW 9 | NNW 4 | SW 8 | SW 11 | SW 10 | SW 10 | SW 10 | SSW 6 | SSW 6 | SSW 9 | SW 10 | SW 10 |
130 | 161 | 336 | 248 | 212 | 96 | 71 | 67 | 47 | 21 | 6 | 11 | 30 | 27 | 25 | 15 | 50 | 36 | 67 | 142 | 74 | |
Swell 2 Height (m) Direction Period (s) | — | SSE 4 | — | — | — | — | — | — | — | — | SW 9 | SW 12 | SSW 8 | — | — | WSW 11 | SSW 10 | SE 4 | — | — | N 4 |
— | 2 | — | — | — | — | — | — | — | — | 21 | 21 | 6 | — | — | 11 | 9 | 1 | — | — | 1 | |
Swell 3 Height (m) Direction Period (s) | — | SW 17 | — | — | — | — | — | — | — | — | SW 13 | NNW 3 | SW 13 | — | — | — | — | SW 10 | — | — | — |
— | 11 | — | — | — | — | — | — | — | — | 7 | 1 | 7 | — | — | — | — | 4 | — | — | — | |
Wind waves Height (m) Direction Period (s) | ENE 4 | ENE 5 | ENE 5 | NE 5 | NE 3 | N 3 | N 5 | N 5 | N 5 | N 4 | — | — | SSW 4 | SSW 4 | SSW 5 | S 5 | ESE 3 | NE 5 | NNW 5 | NNW 4 | S 4 |
2 | 2 | 15 | 22 | 6 | 5 | 61 | 53 | 28 | 13 | — | — | 16 | 20 | 49 | 71 | 5 | 86 | 67 | 26 | 18 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 0 | 0 | 8 | 8 | 0 | 8 | 163 | 8 | 51 | 163 | 163 | 155 | 155 | 155 | 155 | 235 | 249 | 275 | 59 | 98 | 51 |
Best forecast wave conditions in Anglesy | |||||||||||||||||||||
Best forecast wave conditions in United Kingdom | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
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Information about the Trearddur Bay (Holy Island) Surf forecast
The above surf forecast table for Trearddur Bay (Holy Island) provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Trearddur Bay (Holy Island) can be found by selecting the local surf guide option on the grey menu. Our Trearddur Bay (Holy Island) surf forecast is unique since it includes wave energy (power) that defines the real feel of the surf rather than just the height or the period. If you surf the same spot (Trearddur Bay (Holy Island)) regularly then make a mental note of the wave energy from the surf forecast table each time you go. Very soon you may start to choose your surf days based on the wave energy alone combined with our forecast of favourable offshore wind conditions. Our star ratings will help here and of course you will also find the usual wave height and period predictions on our surf forecasts as well as a full break down of the swell components under our advanced users option (to reveal that, click the little Einstein character under the tide times).
Further information to help with frequently asked questions about our surf forecast for Trearddur Bay (Holy Island) may be found under the help tab on the top menu and also by moving your mouse over the question marks on the surf forecast table itself. Please always bear in mind that the forecast is for near-shore open water and local factors at each surf break influence the actual breaking wave height, such as the beach / reef profile, water depths offshore and shelter.
Are you planning a holiday in Anglesy? If you are looking for accommodation near Trearddur Bay (Holy Island), camping, hotels and holiday cottages in Anglesy, consider staying in Holyhead which is 4 km (2 miles) away. Other places in and around Anglesy where you can find information about places to rent, and car hire include Anglesey which is 7 km (4 miles) away, Bangor, Porthmadog and Llandudno.










