Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 31 Aug 2026:
- Most powerful swell: Thursday 3 Sep, 7PM (local time) - 7ft (2.2m), 7s period, SW swell with 434 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 2.2m 7s and forecast to arrive on Thursday (Sep 03) 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 1.1m 5s period and expected on Saturday (Sep 05) at 1PM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 7PM (Thu 3rd Sep) | 7ft (2.2m) 7s |
Table - best surf conditions forecast for Trearddur Bay (Holy Island) over the next 16 days.
The Lowdown
Right then, let’s have a look at what’s coming up for Trearddur Bay (Holy Island). Straight up, I’ve got to be honest with you – the next two weeks are a real mixed bag, and honestly, for the most part, it’s pretty grim. The water is sitting at a touch warmer than normal for this time of year, about 63°, which is a bit of a silver lining.
The problem is, from now, the 31st of August, right through until the 12th of September, every single session is flagged as poor surf conditions. There’s a near-constant stream of cross-shore and onshore wind, mostly from the SW and WSW, blowing between 12 and 25 mph, that’s just going to chop everything up. The combined swell energy is weak to moderate, with values like 149 and 319, but the wind is just too strong and wrong direction to do anything with it. We see a few pulses of swell – up to 7 ft on the 4th of September, and 8 ft on the 15th – but the wind is howling straight onshore, making it a complete mess. That 8 ft on the 15th of September (that’s a Sunday) is for experts only, but with the wind state unknown and onshore, it’s not looking tempting.
Even the smaller windows, like the 5th of September with a 2 ft chest-high wave, are blown out. The 12th of September sees a brief moment of clean conditions with a light breeze from the ESE, but the swell is only 0.7 ft – barely a ripple. This setup, with significant swell and poor quality, is honestly more interesting for kite surfing than paddle surfing.
So, bottom line: there are no recommended waves in this 16-day window. It’s a long, blank stretch, but for this area, a run like this isn't totally out of the ordinary. Forecasts can change, but for now, I’d give the board a rest.
Rusty
Short Range ForecastLight rain (total 7mm), mostly falling on Wed morning. Very mild (max 18°C on Wed afternoon, min 14°C on Mon morning). Mainly fresh winds. | Days 4-6 Weather SummaryLight rain (total 6mm), mostly falling on Thu afternoon. Very mild (max 18°C on Thu morning, min 13°C on Fri night). Winds decreasing (strong winds from the WSW on Fri morning, light winds from the WSW by Sat afternoon). | ||||||||||||||||||||
Monday 31 | Tuesday 1 | Wednesday 2 | Thursday 3 | Friday 4 | Saturday 5 | Sunday 6 | |||||||||||||||
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) | WNW 5 | SW 8 | SSW 7 | SW 4 | SSW 5 | SW 5 | SSW 5 | SSW 6 | SW 6 | SW 5 | SSW 6 | SW 7 | WSW 6 | SW 6 | W 6 | NW 6 | WSW 4 | SW 4 | SSW 4 | SSW 5 | SW 5 |
Wave Graph | |||||||||||||||||||||
87 | 50 | 21 | 16 | 61 | 39 | 69 | 179 | 181 | 106 | 319 | 207 | 299 | 223 | 192 | 100 | 14 | 14 | 35 | 66 | 119 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | cross-on | cross-on | on | on | on | cross-on | cross-on | on | on | on | on | on | cross-on | cross-on | cross-on | cross-on | cross-on | cross-on | cross-on | on |
High Tide | 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 | 4:41AM4.69m | 5:21PM4.55m | 6:18AM4.51m | 7:01PM4.59m | ||||||||
Low Tide | 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 | 10:59AM2.01m | 11:50PM1.99m | 12:31PM2.14m | 1:25AM1.84m | ||||||||
6:24 | — | — | 6:26 | — | — | 6:28 | — | — | 6:30 | — | — | 6:31 | — | — | 6:33 | — | — | 6:35 | — | — | |
— | 8:10 | — | — | 8:08 | — | — | 8:06 | — | — | 8:04 | — | — | 8:01 | — | — | 7:59 | — | — | 7:57 | — | |
mm | — | — | — | — | 1 | 1 | 5 | — | — | 1 | 3 | 2 | — | — | — | — | — | — | — | — | — |
Temp °C | 15 | 17 | 16 | 15 | 17 | 17 | 17 | 18 | 18 | 18 | 18 | 17 | 16 | 18 | 16 | 14 | 15 | 15 | 15 | 15 | 17 |
Feels °C | 9 | 13 | 13 | 11 | 12 | 16 | 12 | 14 | 14 | 15 | 14 | 12 | 8 | 11 | 9 | 9 | 13 | 13 | 8 | 8 | 14 |
Swell 1 Height (m) Direction Period (s) | SW 8 | SW 8 | SSW 7 | — | — | — | SW 16 | SW 16 | SW 15 | — | — | SW 14 | — | SW 14 | SW 14 | SW 6 | NNW 5 | NNW 5 | SW 13 | SW 13 | — |
62 | 50 | 21 | — | — | — | 10 | 10 | 9 | — | — | 8 | — | 8 | 8 | 20 | 23 | 2 | 7 | 6 | — | |
Swell 2 Height (m) Direction Period (s) | — | N 5 | NNW 4 | — | — | — | — | — | — | — | — | — | — | — | — | SW 14 | SW 13 | SW 13 | — | — | — |
— | 7 | 4 | — | — | — | — | — | — | — | — | — | — | — | — | 7 | 7 | 7 | — | — | — | |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | SW 13 | SW 13 | — | — | — |
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 7 | 7 | — | — | — | |
Wind waves Height (m) Direction Period (s) | WNW 5 | WNW 4 | W 3 | SW 4 | SSW 5 | SW 5 | SSW 5 | SSW 6 | SW 6 | SW 5 | SSW 6 | SW 7 | WSW 6 | SW 6 | W 6 | NW 6 | WSW 4 | SW 4 | SSW 4 | SSW 5 | SW 5 |
87 | 23 | 6 | 16 | 61 | 39 | 69 | 179 | 181 | 106 | 319 | 207 | 299 | 223 | 192 | 100 | 14 | 14 | 35 | 66 | 119 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 548 | 51 | 51 | 290 | 292 | 246 | 260 | 288 | 292 | 275 | 290 | 319 | 478 | 548 | 514 | 187 | 51 | 179 | 238 | 299 | 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.











