Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 7 Sep 2026:
- Most powerful swell: Monday 7 Sep, 10PM (local time) - 5ft (1.6m), 7s period, SW swell with 237 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 1.6m 7s and forecast to arrive on Monday (Sep 07) at 10PM. Winds are predicted to be cross-onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.5m 6s period and expected on Wednesday (Sep 09) at 1AM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 10PM (Mon 7th Sep) | 5ft (1.6m) 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 Trearddur Bay (Holy Island) has cooking over the next couple of weeks.
First thing you need to know – this is a bleak run. We’re staring at a full 16-day window, and I can’t find a single moment worth paddling out. Not one. The first few days are a write-off: Monday the 7th has a tiny 1 ft SW swell with a 15 mph onshore wind, water’s sitting at 62° (a touch warmer than usual for this time of year) but it doesn’t matter – that’s a blown-out mess. The week stays stubbornly poor. Tuesday the 8th brings a bit more size at 5 ft from the west, but with a 22 mph cross-onshore wind, it’s lumpy and ugly. Wednesday through the weekend? Same story – small, short-period wind slop or strong onshores.
There is one brief moment on Friday the 11th morning where the wind goes cross-off from the NNW at 15 mph and the conditions turn clean, but the swell is only 2 ft from the SW with a weak 5-second period and low energy (43). It’s barely a ripple. Not worth getting wet for.
Into the second week, things don’t improve. Monday the 14th afternoon has a jump in swell to 6 ft from the SSW with moderate wave energy (202), but it’s accompanied by a 28 mph cross-onshore and messy conditions. That’s more of a kite-surfing setup than anything you’d want to paddle into. The rest of the week tails off into tiny waves or flat spells. By Friday the 18th through to Tuesday the 22nd, we’re looking at near-flat conditions with zero to 2 ft of wind chop and onshores often gusting into the 25–34 mph range. The last day of the outlook, Tuesday the 22nd, has a 3 ft SW swell but with a 31–34 mph onshore gale – unsurfable.
Honestly, there’s nothing to get excited about here. Trearddur Bay is inconsistent at the best of times, and this stretch is a proper blank run. Forecasts can always change, but as it stands, leave the board at home.
Rusty.
Short Range ForecastLight rain (total 4mm), mostly falling on Mon afternoon. Very mild (max 16°C on Mon morning, min 13°C on Mon night). Winds decreasing (strong winds from the WSW on Mon afternoon, light winds from the SW by Wed afternoon). | Days 4-6 Weather SummaryLight rain (total 8mm), mostly falling on Sat afternoon. Very mild (max 17°C on Sat night, min 13°C on Fri night). Winds increasing (calm on Fri night, strong winds from the SSW by Sat afternoon). | ||||||||||||||||||||
Monday 7 | Tuesday 8 | Wednesday 9 | Thursday 10 | Friday 11 | Saturday 12 | Sunday 13 | |||||||||||||||
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 14 | SW 5 | SW 7 | W 5 | WNW 5 | SW 6 | SW 8 | SW 7 | SW 4 | SW 4 | SSW 5 | SW 6 | SW 5 | SW 6 | SW 8 | SW 4 | SW 5 | SSW 6 | SSW 6 | SW 6 | SW 5 |
Wave Graph  | |||||||||||||||||||||
 kJ | 33 | 91 | 219 | 115 | 109 | 8 | 15 | 14 | 26 | 26 | 61 | 136 | 28 | 11 | 16 | 13 | 55 | 191 | 57 | 37 | 33 |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | on | on | on | cross-on | cross-on | cross | cross | on | on | cross-on | on | on | cross-off | cross | cross-on | cross-on | on | on | cross-on | on | cross-on |
High Tide | 8:23PM4.91m | 9:02AM4.96m | 9:21PM5.29m | 9:53AM5.26m | 10:08PM5.63m | 10:36AM5.47m | 10:49PM5.85m | 11:14AM5.59m | 11:28PM5.95m | 11:50AM5.61m | 00:04AM5.91m | 12:25PM5.56m | 00:40AM5.77m | ||||||||
Low Tide | 1:57PM1.96m | 2:38AM1.44m | 3:00PM1.61m | 3:33AM1.02m | 3:50PM1.24m | 4:19AM0.68m | 4:32PM0.95m | 5:00AM0.47m | 5:11PM0.75m | 5:39AM0.42m | 5:49PM0.68m | 6:16AM0.50m | 6:26PM0.74m | ||||||||
 |  |  | | |  |  | |  | |  | | | |  | |  | | | | | |
 | 6:37 | — | — | 6:39 | — | — | 6:39 | — | — | 6:41 | — | — | 6:43 | — | — | 6:45 | — | — | 6:47 | — | — |
 | — | 7:53 | — | — | 7:52 | — | — | 7:50 | — | — | 7:46 | — | — | 7:45 | — | — | 7:42 | — | — | 7:39 | — |
mm | — | 2 | 1 | — | 1 | — | — | — | — | — | — | 2 | — | — | — | — | 4 | 2 | — | — | — |
Temp °C | 16 | 16 | 13 | 14 | 16 | 15 | 13 | 14 | 15 | 15 | 16 | 15 | 15 | 15 | 15 | 14 | 15 | 17 | 16 | 16 | 16 |
Feels °C | 11 | 10 | 8 | 6 | 9 | 8 | 8 | 11 | 10 | 9 | 10 | 9 | 11 | 14 | 14 | 8 | 8 | 13 | 13 | 13 | 13 |
Swell 1 Height (m) Direction Period (s) | SW 14 | — | SW 12 | SW 11 | SW 11 | SW 6 | SW 8 | NNW 5 | — | — | — | — | SW 5 | SW 6 | SW 8 | — | SW 7 | — | SSW 6 | — | — |
| kJ | 33 | — | 6 | 5 | 5 | 8 | 15 | 16 | — | — | — | — | 28 | 9 | 16 | — | 2 | — | 57 | — | — |
Swell 2 Height (m) Direction Period (s) | — | — | WSW 12 | — | SW 10 | SW 11 | — | SW 7 | — | — | — | — | WSW 9 | SW 8 | NNW 4 | — | — | — | — | — | — |
| kJ | — | — | 14 | — | 4 | 4 | — | 14 | — | — | — | — | 7 | 11 | 1 | — | — | — | — | — | — |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| kJ | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Wind waves Height (m) Direction Period (s) | WSW 4 | SW 5 | SW 7 | W 5 | WNW 5 | NNW 6 | NNW 6 | W 3 | SW 4 | SW 4 | SSW 5 | SW 6 | WNW 4 | NW 4 | — | SW 4 | SW 5 | SSW 6 | — | SW 6 | SW 5 |
| kJ | 32 | 91 | 219 | 115 | 109 | 139 | 74 | 2 | 26 | 26 | 61 | 136 | 8 | 5 | — | 13 | 55 | 191 | — | 37 | 33 |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 174 | 326 | 167 | 195 | 548 | 179 | 192 | 195 | 187 | 280 | 253 | 305 | 179 | 179 | 155 | 238 | 305 | 246 | 51 | 51 | 179 |
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)
FREE! Surf-Forecast.com widget for your website
The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Trearddur Bay (Holy Island) surf forecast. Simply grab the html code snippet that we provide and paste it into your own site. You can choose your preferred language and metric/imperial units for the surf forecast feed to suit users of your site. Click here to get the code.
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.
Nearest