Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 29 Aug 2026:
- Most powerful swell: Wednesday 2 Sep, 7PM (local time) - 8ft (2.5m), 7s period, SW swell with 773 kJ wave energy.
Best Forecast Surf Conditions for Trearddur Bay (Holy Island) this week:
The most powerful waves expected at Trearddur Bay (Holy Island) in the next 16 days are 2.5m 7s and forecast to arrive on Wednesday (Sep 02) at 7PM. Winds are predicted to be onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.7m 5s period and expected on Monday (Aug 31) at 4PM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 7PM (Wed 2nd Sep) | 8ft (2.5m) 7s |
Table - best surf conditions forecast for Trearddur Bay (Holy Island) over the next 16 days.
The Lowdown
Alright, Rusty here. Let's have a look at what we've got for the next couple of weeks.
Honestly, it's a bit of a tough stretch for Trearddur Bay (Holy Island). The water is sitting at 64°, which is a touch warmer than we'd expect for this time of year, so that's a bit of a silver lining if you're just getting in the water.
The first week is pretty grim. We’ve got a run of small, short-period windswell with mostly onshore and cross-onshore winds. Saturday the 29th of August through Monday the 7th of September is all very poor surf conditions, with most days scoring a zero. There's a brief flicker of hope on Monday the 7th of September morning, with a NE offshore wind cleaning up a 4ft swell from the W. It’s described as "surfable but very ordinary," and the combined energy is only 96, so it's weak. The afternoon is a bit cleaner too, but with the same weak energy. It's not a standout, but it's the only window where the wind is working for us at all.
Then we get into the second week, and it goes quiet again. From Tuesday the 8th of September all the way through to Sunday the 13th of September, the surf is tiny or non-existent. A few days have zero swell energy, and the other days are just battered by strong winds. It's a long, flat, and messy run.
The only real moment worth mentioning in the whole 16-day period is that Monday the 7th of September. The swell is small, but the offshore wind from the NE will make it the cleanest we'll see. It's a beginner-friendly 4ft from the W, but the period is short (5 seconds), so don't expect much push. It's not a classic, but it's the only show in town.
So, for the dedicated locals, keep an eye on that Monday morning. Otherwise, this stretch is a write-off for decent waves. The consistency is poor, and the forecasts are what they are.
Rusty.
Short Range ForecastLight rain (total 8mm), mostly falling on Sat morning. Very mild (max 17°C on Mon night, min 14°C on Sun night). Winds increasing (light winds from the WNW on Sat night, strong winds from the NW by Mon morning). | Days 4-6 Weather SummaryLight rain (total 8mm), mostly falling on Tue night. Very mild (max 17°C on Wed morning, min 14°C on Thu night). Winds decreasing (strong winds from the SW on Wed afternoon, moderate winds from the WSW by Thu afternoon). | ||||||||||||||||||||
Saturday 29 | Sunday 30 | Monday 31 | Tuesday 1 | Wednesday 2 | Thursday 3 | Friday 4 | |||||||||||||||
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) | SSW 6 | SSW 6 | SSW 8 | SSW 8 | SSW 5 | SW 7 | NW 6 | SW 8 | SSW 7 | SW 4 | SW 5 | SSW 5 | SSW 6 | SSW 7 | SW 7 | SW 6 | SW 7 | WSW 5 | SW 7 | WSW 6 | W 6 |
Wave Graph | |||||||||||||||||||||
44 | 25 | 126 | 90 | 48 | 119 | 154 | 50 | 21 | 21 | 73 | 51 | 279 | 444 | 432 | 154 | 135 | 97 | 490 | 238 | 233 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | off | cross-on | cross-on | cross-on | cross-on | cross | cross-on | on | on | on | on | on | on | on | on | on | on | cross-on | cross-on | cross-on |
High Tide | 11:57AM5.33m | 00:07AM5.72m | 12:28PM5.40m | 00:40AM5.74m | 1:01PM5.41m | 1:15AM5.69m | 1:36PM5.36m | 1:53AM5.56m | 2:15PM5.23m | 2:36AM5.34m | 3:01PM5.01m | 3:30AM5.02m | 3:59PM4.75m | ||||||||
Low Tide | 5:55PM0.94m | 6:16AM0.70m | 6:28PM0.87m | 6:50AM0.69m | 7:04PM0.89m | 7:26AM0.78m | 7:42PM1.01m | 8:06AM0.98m | 8:25PM1.22m | 8:51AM1.28m | 9:16PM1.51m | 9:47AM1.66m | 10:23PM1.82m | ||||||||
6:20 | — | — | 6:22 | — | — | 6:24 | — | — | 6:26 | — | — | 6:28 | — | — | 6:30 | — | — | 6:31 | — | — | |
— | 8:15 | — | — | 8:13 | — | — | 8:10 | — | — | 8:08 | — | — | 8:06 | — | — | 8:04 | — | — | 8:01 | — | |
mm | 4 | 2 | — | 1 | 1 | — | — | — | — | — | — | 8 | — | — | — | — | — | — | 1 | — | 3 |
Temp °C | 16 | 16 | 15 | 16 | 16 | 16 | 14 | 16 | 17 | 16 | 16 | 16 | 17 | 17 | 17 | 16 | 17 | 15 | 15 | 17 | 17 |
Feels °C | 15 | 15 | 14 | 12 | 10 | 13 | 6 | 12 | 14 | 11 | 11 | 12 | 12 | 11 | 12 | 10 | 12 | 8 | 8 | 15 | 11 |
Swell 1 Height (m) Direction Period (s) | SSW 6 | SSW 6 | SSW 8 | — | SW 8 | SW 7 | SW 8 | NNW 5 | SSW 7 | — | — | WNW 4 | — | — | SW 15 | SW 14 | SW 14 | — | — | SW 14 | SW 14 |
44 | 25 | 126 | — | 16 | 119 | 64 | 28 | 21 | — | — | 1 | — | — | 9 | 8 | 8 | — | — | 8 | 8 | |
Swell 2 Height (m) Direction Period (s) | — | SE 4 | NNW 3 | — | — | — | — | SW 8 | NNW 5 | — | — | — | — | — | — | — | — | — | — | NW 6 | — |
— | 1 | 1 | — | — | — | — | 50 | 5 | — | — | — | — | — | — | — | — | — | — | 2 | — | |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | |
Wind waves Height (m) Direction Period (s) | — | NNE 2 | NW 3 | SSW 8 | SSW 5 | — | NW 6 | W 5 | SW 3 | SW 4 | SW 5 | SSW 5 | SSW 6 | SSW 7 | SW 7 | SW 6 | SW 7 | WSW 5 | SW 7 | WSW 6 | W 6 |
— | 1 | 1 | 90 | 48 | — | 154 | 21 | 3 | 21 | 73 | 51 | 279 | 444 | 432 | 154 | 135 | 97 | 490 | 238 | 233 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 208 | 192 | 51 | 255 | 223 | 51 | 305 | 51 | 179 | 305 | 251 | 246 | 246 | 503 | 284 | 350 | 548 | 548 | 556 | 51 | 251 |
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.











