
Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 4 Sep 2026:
- Most powerful swell: Thursday 10 Sep, 7AM (local time) - 6ft (1.9m), 6s period, SSW swell with 295 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 1.9m 6s and forecast to arrive on Thursday (Sep 10) at 7AM. Winds are predicted to be onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.3m 5s period and expected on Wednesday (Sep 09) at 7PM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 7AM (Thu 10th Sep) | 6ft (1.9m) 6s |
Table - best surf conditions forecast for Trearddur Bay (Holy Island) over the next 16 days.
The Lowdown
Alright, this is Rusty here, and I’ve gotta be straight with you – it’s a tough outlook for Trearddur Bay (Holy Island). The forecast is pretty much a write-off for the next 16 days, with no real surf to get excited about.
We start off on Friday the 4th of September with a 1.8m swell from the WSW, but the wind is a nasty 25 mph cross-on, making it a complete mess. The combined energy is moderate at 201, but it’s all for nothing with that wind. The water temp is 63°, which is a touch warmer than normal for this time of year, but that’s not much comfort. Conditions stay poor all weekend and into the next week, with strong onshore winds and lumpy, choppy seas. The swell hangs around, but it’s never clean.
The real kicker is the wind. From the 4th right through to the 17th, every session is rated as poor surf conditions. There’s a brief moment on the 18th of September, Friday morning, where we finally see a moderate offshore wind from the ENE, and a 1.8m swell from the WNW rolls in, with a combined energy of 222. That’s our one and only standout. It’s surfable, but the guidance says it’s very ordinary conditions. It’s the best on offer, but it’s nothing to write home about. The rest of the time, it’s flat or blown out, with a long stretch of nothing from the 12th to the 17th where the swell drops to almost nothing.
In short, don’t bother checking the cams for a while. It’s a bleak run, and a blank spell like this is more normal for the area when the wind won’t play ball. Forecasts can change, but right now, hold off.
Stay tuned, and maybe go for a longboard walk on the beach instead.
- Rusty
Short Range ForecastLight rain (total 5mm), mostly falling on Sat night. Very mild (max 18°C on Sun morning, min 13°C on Fri night). Winds increasing (light winds from the SW on Sat morning, strong winds from the S by Sun morning). | Days 4-6 Weather SummaryLight rain (total 5mm), mostly falling on Wed night. Very mild (max 16°C on Mon afternoon, min 13°C on Mon night). Winds decreasing (near gales from the SSW on Mon afternoon, moderate winds from the SW by Wed night). | ||||||||||||||||||||
Friday 4 | Saturday 5 | Sunday 6 | Monday 7 | Tuesday 8 | Wednesday 9 | Thursday 10 | |||||||||||||||
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) | WSW 5 | WSW 6 | W 5 | W 5 | SW 6 | SSW 4 | SSW 6 | SSW 6 | SW 6 | SW 14 | SW 5 | WSW 6 | WSW 6 | WSW 6 | WNW 6 | WNW 5 | W 5 | SSW 5 | SSW 6 | SW 7 | W 5 |
Wave Graph | |||||||||||||||||||||
176 | 119 | 117 | 47 | 26 | 44 | 122 | 156 | 112 | 42 | 166 | 243 | 223 | 143 | 167 | 106 | 46 | 83 | 176 | 111 | 52 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-on | cross-on | cross-on | cross-on | on | cross-on | cross-on | cross-on | cross-on | on | cross-on | cross-on | cross-on | cross-on | cross-on | cross-on | on | cross-on | on | on | cross-on |
High Tide | 3:59PM4.75m | 4:41AM4.69m | 5:21PM4.55m | 6:18AM4.51m | 7:01PM4.59m | 7:54AM4.65m | 8:23PM4.91m | 9:02AM4.96m | 9:21PM5.29m | 9:53AM5.26m | 10:08PM5.63m | 10:36AM5.47m | 10:49PM5.85m | ||||||||
Low Tide | 10:23PM1.82m | 10:59AM2.01m | 11:50PM1.99m | 12:31PM2.14m | 1:25AM1.84m | 1:57PM1.96m | 2:38AM1.44m | 3:00PM1.61m | 3:33AM1.02m | 3:50PM1.24m | 4:19AM0.68m | 4:32PM0.95m | |||||||||
6:31 | — | — | 6:33 | — | — | 6:35 | — | — | 6:37 | — | — | 6:39 | — | — | 6:39 | — | — | 6:41 | — | — | |
— | 8:01 | — | — | 7:59 | — | — | 7:57 | — | — | 7:53 | — | — | 7:52 | — | — | 7:50 | — | — | 7:46 | — | |
mm | — | — | — | — | — | 5 | — | — | — | — | — | 1 | — | — | — | — | — | 4 | — | — | — |
Temp °C | 16 | 17 | 16 | 14 | 14 | 15 | 18 | 18 | 17 | 15 | 16 | 13 | 14 | 15 | 14 | 14 | 15 | 16 | 17 | 18 | 17 |
Feels °C | 10 | 11 | 9 | 11 | 10 | 10 | 11 | 11 | 12 | 11 | 6 | 6 | 6 | 7 | 6 | 8 | 10 | 14 | 14 | 13 | 12 |
Swell 1 Height (m) Direction Period (s) | SW 14 | SW 14 | SW 14 | SW 14 | NW 4 | — | SW 13 | SW 13 | SW 6 | SW 14 | — | — | — | SW 11 | — | S 10 | — | — | — | — | SW 7 |
8 | 8 | 8 | 7 | 4 | — | 7 | 6 | 112 | 32 | — | — | — | 5 | — | 2 | — | — | — | — | 25 | |
Swell 2 Height (m) Direction Period (s) | — | — | — | — | NNW 5 | — | — | — | SW 12 | — | — | — | — | — | — | — | — | — | — | — | — |
— | — | — | — | 2 | — | — | — | 6 | — | — | — | — | — | — | — | — | — | — | — | — | |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | SW 13 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
— | — | — | — | 7 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | |
Wind waves Height (m) Direction Period (s) | WSW 5 | WSW 6 | W 5 | W 5 | SW 6 | SSW 4 | SSW 6 | SSW 6 | — | WSW 4 | SW 5 | WSW 6 | WSW 6 | WSW 6 | WNW 6 | WNW 5 | W 5 | SSW 5 | SSW 6 | SW 7 | W 5 |
176 | 119 | 117 | 47 | 26 | 44 | 122 | 156 | — | 42 | 166 | 243 | 223 | 143 | 167 | 106 | 46 | 83 | 176 | 111 | 52 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 306 | 514 | 179 | 192 | 235 | 186 | 238 | 346 | 125 | 51 | 326 | 174 | 804 | 515 | 379 | 285 | 251 | 253 | 162 | 326 | 548 |
Best forecast wave conditions in Anglesy | |||||||||||||||||||||
Best forecast wave conditions in United Kingdom | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)
Wind Speed (km/h)
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.










