
Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 11 Jul 2026:
- Most powerful swell: Tuesday 14 Jul, 1PM (local time) - 0.5ft (0.1m), 18s period, SW swell with 12 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 0.1m 18s and forecast to arrive on Tuesday (Jul 14) at 1PM. Winds are predicted to be offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.2m 6s period and expected on Saturday (Jul 18) at 7AM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 1PM (Tue 14th Jul) | 0.5ft (0.1m) 18s |
Table - best surf conditions forecast for Trearddur Bay (Holy Island) over the next 16 days.
Alright, let’s talk about Trearddur Bay. I’ve scanned the charts, and mate, it’s a tough 16 days ahead. This stretch is about as flat as it gets – nothing much to get excited about.
Starting Saturday the 11th of July, we’ve got zero combined swell energy – the ocean’s a mirror with no surf. That pattern sticks around all week and into the next. We get some clean offshore wind on Sunday the 12th and Monday the 13th, but there’s no swell to go with it. Tiny 0.3ft dribbles from the south with long periods up to 19 seconds – all that deep ocean groundswell energy just doesn’t have any oomph behind it. Trearddur Bay stays flat.
Come Tuesday the 20th, a little pulse of 3ft from the northwest appears, but it’s short-period windswell at 4 seconds and the wind’s messy cross-onshore. The combined energy is only 23 (weak), and the surf is poor.
There’s one day, Wednesday the 22nd of July, where the swell reaches 4ft from the west-northwest – the biggest in the whole run – with combined energy hitting 77. But the period is still short at 5 seconds, and we’ve got a 30 km/h cross-onshore wind from the west-southwest. That’s lumpy, choppy, and more suited for a kite than a surfboard. It’s too rough for beginners and not clean enough for a good ride.
After that, it’s back to small, near-flat conditions right through to Sunday the 26th. The combined energy mostly sits in single digits. A glassy moment on the 16th, but with a 0.3ft swell, you’re just bobbing around.
So, no standout days here. No waves worth calling out. If you’re really keen, the 22nd might give you a short, bumpy run on a foamie. For the rest, it’s a blank run. Trearddur Bay sees these flat spells – it’s normal for the area. Forecasts can always change, but for now, keep the board stored.
Rusty.
Short Range ForecastMostly dry. Warm (max 23°C on Sat morning, min 14°C on Sun night). Winds increasing (light winds from the NNE on Sat morning, fresh winds from the NE by Sun afternoon). | Days 4-6 Weather SummaryModerate rain (total 10mm), heaviest on Thu morning. Warm (max 23°C on Tue night, min 16°C on Mon night). Winds decreasing (fresh winds from the ENE on Mon night, calm by Thu morning). | ||||||||||||||||||||
Saturday 11 | Sunday 12 | Monday 13 | Tuesday 14 | Wednesday 15 | Thursday 16 | Friday 17 | |||||||||||||||
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) | NNW 5 | NNW 5 | N 4 | NE 5 | NE 4 | NE 5 | NE 4 | S 19 | S 15 | S 18 | SW 18 | SW 14 | SW 16 | SW 16 | SSW 7 | SSW 7 | SW 14 | SSW 6 | SW 7 | SW 6 | SW 13 |
Wave Graph | |||||||||||||||||||||
0 | 0 | 0 | 0 | 0 | 0 | 0 | 7 | 4 | 6 | 12 | 7 | 10 | 10 | 7 | 8 | 8 | 4 | 11 | 10 | 6 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | off | cross-off | off | off | off | off | off | off | off | cross-off | off | off | cross-off | cross-off | glassy | cross-off | cross-off | cross-off | cross-off |
High Tide | 7:51AM4.85m | 8:33PM4.86m | 9:01AM5.02m | 9:34PM5.14m | 10:03AM5.23m | 10:28PM5.42m | 10:57AM5.41m | 11:18PM5.67m | 11:48AM5.52m | 00:06AM5.82m | 12:36PM5.53m | 00:52AM5.87m | 1:23PM5.44m | 1:37AM5.79m | |||||||
Low Tide | 2:09PM1.44m | 2:44AM1.43m | 3:11PM1.28m | 3:45AM1.10m | 4:08PM1.09m | 4:40AM0.77m | 4:59PM0.91m | 5:31AM0.52m | 5:47PM0.80m | 6:20AM0.38m | 6:34PM0.77m | 7:08AM0.38m | 7:20PM0.84m | ||||||||
5:03 | — | — | 5:05 | — | — | 5:05 | — | — | 5:07 | — | — | 5:07 | — | — | 5:09 | — | — | 5:11 | — | — | |
— | — | 9:43 | — | — | 9:42 | — | — | 9:40 | — | — | 9:39 | — | — | 9:38 | — | — | 9:37 | — | — | 9:36 | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 3 | 4 | 3 | 10 | 3 | — | — |
Temp °C | 23 | 23 | 22 | 22 | 23 | 22 | 18 | 20 | 19 | 19 | 22 | 23 | 20 | 23 | 22 | 20 | 20 | 19 | 18 | 18 | 17 |
Feels °C | 22 | 21 | 18 | 19 | 18 | 16 | 11 | 14 | 12 | 14 | 17 | 17 | 15 | 19 | 20 | 22 | 21 | 18 | 16 | 15 | 16 |
Swell 1 Height (m) Direction Period (s) | NNW 5 | — | N 4 | N 4 | — | — | — | S 19 | S 15 | S 18 | SW 18 | S 6 | S 6 | SW 7 | NNE 5 | SSW 7 | SSW 6 | N 4 | SW 7 | SW 6 | SSW 6 |
37 | — | 19 | 1 | — | — | — | 7 | 4 | 6 | 12 | 1 | 1 | 2 | 23 | 4 | 4 | 9 | 11 | 10 | 3 | |
Swell 2 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | S 7 | SW 14 | SW 16 | SW 9 | SSW 7 | SW 14 | SW 14 | SSW 6 | S 12 | SW 12 | SW 13 |
— | — | — | — | — | — | — | — | — | — | 1 | 7 | 10 | 3 | 5 | 8 | 8 | 4 | 3 | 6 | 6 | |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | S 15 | — | S 14 | — | — | S 13 | SW 16 | SW 13 | SW 14 | — | S 12 | — | — | — |
— | — | — | — | — | — | — | 4 | — | 4 | — | — | 3 | 10 | 7 | 8 | — | 3 | — | — | — | |
Wind waves Height (m) Direction Period (s) | — | NNW 5 | — | NE 5 | NE 4 | NE 5 | NE 4 | NE 4 | NE 4 | NE 4 | NNE 4 | NE 5 | NE 5 | NE 5 | — | NNE 4 | NNE 4 | — | NNE 4 | N 3 | N 5 |
— | 23 | — | 17 | 40 | 32 | 34 | 40 | 20 | 26 | 35 | 48 | 21 | 22 | — | 11 | 6 | — | 5 | 3 | 49 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 267 | 260 | 249 | 287 | 208 | 305 | 410 | 364 | 286 | 184 | 163 | 267 | 184 | 163 | 298 | 280 | 328 | 208 | 299 | 625 | 706 |
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.










