Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 26 Aug 2026:
- Most powerful swell: Wednesday 2 Sep, 10PM (local time) - 7ft (2.2m), 6s period, SSW swell with 418 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 6s and forecast to arrive on Wednesday (Sep 02) 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 0.5m 4s period and expected on Thursday (Aug 27) at 4AM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 10PM (Wed 2nd Sep) | 7ft (2.2m) 6s |
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’s cookin' for Trearddur Bay.
To be honest, mate, this is a tough one to write. I’ve scanned the whole 16-day window and there’s not a single session that gets the nod. The whole run is a write-off. For the first week, the wind is all over the place – cross, cross-on, and onshore – and the swell is tiny and weak. The energy readings are mostly in the double digits, barely cracking 100 a couple of times, and even then the wind’s junk. The one time we get a bit of size, like Sunday 30th August afternoon with a 6 ft swell from the SSW, the wind is a 22 mph cross-onshore, turning it into a lumpy mess. Same story on the 1st of September and the 4th of September – swell height gets up to 4 ft and 7 ft, but the wind is a fresh cross-onshore, so it’s all chop and no joy.
The second week, from the 6th of September onward, the swell just disappears. We’re talking 0.3 ft to 1.0 ft with periods so short they barely count. The wind might go cross-off for a few days, but there’s no wave to push around. It’s flat, flat, flat.
Water temp at the start of the window is 63°, which is a touch warmer than normal for this time of year, but you won’t be feeling it because you won’t be in the water. Trearddur Bay is a beginner spot that’s inconsistent, and this stretch of 16 days shows exactly why – it’s not a place you can rely on for a guaranteed wave. This blank run is more normal for the area than a miracle run.
So, there’s nothing to chase. Put the board away, maybe check the forecast again in a week. Sometimes these patterns shift, but right now, it’s a hard no.
Rusty.
Short Range ForecastHeavy rain (total 32mm), heaviest during Thu afternoon. Warm (max 22°C on Wed afternoon, min 16°C on Wed night). Wind will be generally light. | Days 5-7 Weather SummaryHeavy rain (total 20mm), heaviest during Sun afternoon. Very mild (max 17°C on Sun afternoon, min 13°C on Mon night). Mainly fresh winds. | |||||||||||||||||||
Wed 26 | Thursday 27 | Friday 28 | Saturday 29 | Sunday 30 | Monday 31 | Tuesday 1 | ||||||||||||||
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 8 | SSW 7 | SSW 7 | SSW 7 | SSW 3 | SSW 5 | SSW 7 | SSW 7 | SSW 7 | SSW 6 | SW 8 | SW 9 | SSW 8 | SSW 7 | WNW 5 | SW 8 | WSW 6 | W 6 | W 5 | SW 6 |
Wave Graph | ||||||||||||||||||||
12 | 5 | 6 | 4 | 8 | 48 | 75 | 59 | 116 | 33 | 166 | 81 | 99 | 113 | 91 | 101 | 143 | 230 | 74 | 18 | |
Wind (km/h) | ||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | off | cross-off | cross-on | cross-on | on | on | cross-off | off | cross | cross-on | cross-on | cross-on | cross-on | on | cross-on | cross-on | cross-on | cross |
High Tide | 10:33PM5.32m | 10:57AM5.08m | 11:04PM5.51m | 11:27AM5.23m | 11:36PM5.65m | 11:57AM5.33m | 00:07AM5.72m | 12:28PM5.40m | 00:40AM5.74m | 1:01PM5.41m | 1:15AM5.69m | 1:36PM5.36m | 1:53AM5.56m | |||||||
Low Tide | 4:21PM1.52m | 4:43AM1.19m | 4:52PM1.28m | 5:14AM0.96m | 5:23PM1.07m | 5:44AM0.80m | 5:55PM0.94m | 6:16AM0.70m | 6:28PM0.87m | 6:50AM0.69m | 7:04PM0.89m | 7:26AM0.78m | 7:42PM1.01m | |||||||
— | — | 6:18 | — | — | 6:20 | — | — | 6:20 | — | — | 6:22 | — | — | 6:24 | — | — | 6:26 | — | — | |
8:22 | — | — | 8:20 | — | — | 8:17 | — | — | 8:15 | — | — | 8:13 | — | — | 8:10 | — | — | 8:08 | — | |
mm | — | 2 | 3 | 14 | 2 | 5 | 1 | — | 5 | 7 | 1 | — | 6 | — | — | — | 6 | — | — | — |
Temp °C | 22 | 21 | 16 | 17 | 16 | 16 | 18 | 18 | 16 | 16 | 15 | 16 | 17 | 15 | 15 | 15 | 15 | 14 | 15 | 15 |
Feels °C | 21 | 19 | 13 | 16 | 17 | 13 | 15 | 16 | 15 | 15 | 10 | 13 | 12 | 12 | 10 | 9 | 10 | 9 | 11 | 12 |
Swell 1 Height (m) Direction Period (s) | SSW 8 | SSW 7 | SSW 7 | NE 4 | N 4 | SSW 5 | SSW 7 | SSW 7 | SSW 7 | SSW 6 | SW 8 | N 4 | — | — | SW 8 | WNW 5 | — | — | — | SW 6 |
12 | 5 | 5 | 5 | 1 | 48 | 75 | 59 | 116 | 33 | 166 | 3 | — | — | 60 | 19 | — | — | — | 18 | |
Swell 2 Height (m) Direction Period (s) | — | SSW 4 | — | SSW 7 | S 12 | — | — | — | NNW 5 | — | NNW 4 | W 3 | — | — | SW 11 | NNW 5 | — | — | — | — |
— | 2 | — | 4 | 3 | — | — | — | 5 | — | 5 | 1 | — | — | 18 | 9 | — | — | — | — | |
Swell 3 Height (m) Direction Period (s) | S 12 | S 12 | SW 12 | S 12 | — | S 12 | — | S 11 | — | — | — | — | — | — | — | — | — | — | — | — |
3 | 3 | 6 | 3 | — | 3 | — | 2 | — | — | — | — | — | — | — | — | — | — | — | — | |
Wind waves Height (m) Direction Period (s) | NE 5 | NE 4 | NE 5 | — | SSW 3 | — | — | — | — | N 2 | — | SW 9 | SSW 8 | SSW 7 | WNW 5 | SW 8 | WSW 6 | W 6 | W 5 | NW 4 |
3 | 4 | 8 | — | 8 | — | — | — | — | 1 | — | 81 | 99 | 113 | 91 | 101 | 143 | 230 | 74 | 8 | |
Nearest Offshore or Glassy | ||||||||||||||||||||
Distance (km) | 316 | 275 | 249 | 285 | 208 | 51 | 284 | 251 | 8 | 514 | 50 | 249 | 96 | 174 | 280 | 292 | 390 | 179 | 364 | 161 |
Best forecast wave conditions in Anglesy | ||||||||||||||||||||
Best forecast wave conditions in United Kingdom | ||||||||||||||||||||
Header Global | ||||||||||||||||||||
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Live Wind Speed (km/h)
Surf Rating (10 Max)
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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.











