Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 23 Aug 2026:
- Most powerful swell: Sunday 30 Aug, 1PM (local time) - 6ft (1.9m), 6s period, WNW swell with 230 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 Sunday (Aug 30) at 1PM. Winds are predicted to be cross-shore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.9m 4s period and expected on Tuesday (Aug 25) at 10PM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 1PM (Sun 30th Aug) | 6ft (1.9m) 6s |
Table - best surf conditions forecast for Trearddur Bay (Holy Island) over the next 16 days.
The Lowdown
Right, let’s be straight with you. The outlook for Trearddur Bay (Holy Island) over the next 16 days is a tough one. There’s genuinely not a single session I’d recommend paddling out for. We’re looking at a blank run that stretches all the way from now through to the end of the first week of September, with zero decent options on the table.
Starting off this Sunday the 23rd of August, we’ve got tiny 0.3ft swell with a light north breeze. The combined energy is a paltry 8, so there’s just nothing for the wave to work with. That pattern holds through Monday and Tuesday – still flat with weak energy readings in the single digits. Not worth the drive.
By Wednesday the 26th, the swell nudges up to 1ft and the period drops to 8 seconds. The energy climbs to the low 20s, but that’s still not enough to push anything rideable. Thursday morning brings heavy rain and a cross-on wind, and even though the swell hits 3ft by the afternoon with 110 energy, it’s all messy and onshore. Not happening.
Friday and Saturday get a little punchy – we see 6ft to 7ft swells on Saturday the 29th with energy up to 320. But the period is a short 6 seconds, and the wind is a moderate cross-on from the west. It’s choppy and blown out. That’s kite-surfing territory, not for a smooth paddle session.
The following week doesn’t get any better. Sunday the 30th has 6ft and fresh cross-on wind, Monday the 31st drops back to 2ft, and Tuesday the 1st of September is back to tiny 0.7ft with a fresh offshore breeze. Even with clean wind, there’s just no swell to catch.
We get a brief uptick around Thursday the 3rd of September, with 7ft on the afternoon and a combined energy of 384. But again, it’s a short 7-second period and cross-on wind from the SSW. Too lumpy for a good ride, and at that size with the chop, it’s only for the brave. Friday the 4th drops back to 4ft and onshore, and by the weekend it’s all messy again.
The outlook is bleak. No standouts, no hidden gems. This stretch looks like a write-off for Trearddur Bay. Sometimes the ocean just says no, and this is one of those times. Keep an eye on the charts, though – it can’t stay this poor forever.
Rusty.
Short Range ForecastLight rain (total 6mm), mostly falling on Tue night. Warm (max 23°C on Tue afternoon, min 13°C on Sun morning). Winds increasing (calm on Mon morning, fresh winds from the E by Tue night). | Days 4-6 Weather SummaryLight rain (total 8mm), mostly falling on Wed night. Warm (max 20°C on Wed afternoon, min 15°C on Fri night). Winds increasing (light winds from the SE on Wed night, fresh winds from the SSW by Fri night). | ||||||||||||||||||||
Sunday 23 | Monday 24 | Tuesday 25 | Wednesday 26 | Thursday 27 | Friday 28 | Saturday 29 | |||||||||||||||
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 14 | SW 14 | SW 14 | SW 13 | SW 13 | SW 13 | SW 13 | SSW 8 | SSW 8 | SSW 8 | SSW 7 | SSW 7 | SSW 7 | SSW 8 | SSW 7 | SSW 7 | SSW 7 | SSW 7 | SW 4 | W 5 |
Wave Graph | |||||||||||||||||||||
8 | 7 | 7 | 8 | 7 | 7 | 7 | 7 | 7 | 13 | 12 | 5 | 25 | 125 | 157 | 48 | 33 | 20 | 31 | 22 | 119 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | off | glassy | cross-off | cross-off | cross-off | off | cross-off | cross-on | on | cross | cross-on | on | on | cross-on | on | cross-on | cross-on | on | on |
High Tide | 8:27PM4.49m | 9:08AM4.41m | 9:19PM4.79m | 9:52AM4.67m | 9:59PM5.08m | 10:26AM4.89m | 10:33PM5.32m | 10:57AM5.08m | 11:04PM5.51m | 11:27AM5.23m | 11:36PM5.65m | 11:57AM5.33m | 00:07AM5.72m | ||||||||
Low Tide | 2:08PM2.34m | 2:47AM2.11m | 3:05PM2.09m | 3:35AM1.78m | 3:46PM1.80m | 4:11AM1.47m | 4:21PM1.52m | 4:43AM1.19m | 4:52PM1.28m | 5:14AM0.96m | 5:23PM1.07m | 5:44AM0.80m | 5:55PM0.94m | ||||||||
6:11 | — | — | 6:13 | — | — | 6:13 | — | — | 6:16 | — | — | 6:18 | — | — | 6:20 | — | — | 6:20 | — | — | |
— | 8:29 | — | — | 8:27 | — | — | 8:24 | — | — | 8:22 | — | — | 8:20 | — | — | 8:17 | — | — | 8:15 | — | |
mm | — | — | — | — | — | — | — | — | 6 | — | — | 2 | 1 | 2 | — | — | — | 3 | 2 | 6 | 8 |
Temp °C | 14 | 15 | 17 | 18 | 20 | 19 | 20 | 23 | 20 | 19 | 20 | 18 | 17 | 17 | 16 | 16 | 17 | 16 | 16 | 16 | 16 |
Feels °C | 11 | 12 | 14 | 16 | 18 | 14 | 17 | 19 | 13 | 16 | 19 | 17 | 16 | 17 | 15 | 15 | 15 | 14 | 12 | 12 | 11 |
Swell 1 Height (m) Direction Period (s) | N 4 | SW 14 | SW 13 | SW 10 | SW 9 | SW 13 | SW 13 | SW 13 | SSW 8 | SSW 8 | SSW 8 | SSW 7 | SSW 7 | NE 4 | SSW 8 | SSW 7 | SSW 7 | SSW 7 | SSW 7 | NW 4 | — |
6 | 7 | 7 | 4 | 3 | 7 | 7 | 7 | 7 | 13 | 12 | 5 | 25 | 1 | 157 | 48 | 33 | 20 | 31 | 2 | — | |
Swell 2 Height (m) Direction Period (s) | SW 14 | — | — | SW 14 | — | SW 9 | SW 8 | SW 8 | S 13 | NE 5 | NE 4 | SSW 4 | NE 4 | S 12 | — | S 12 | S 12 | SSW 10 | SW 7 | — | — |
8 | — | — | 8 | — | 3 | 3 | 3 | 3 | 4 | 1 | 1 | 1 | 3 | — | 3 | 3 | 10 | 19 | — | — | |
Swell 3 Height (m) Direction Period (s) | — | — | SW 14 | — | SW 13 | — | NE 5 | — | — | S 12 | S 12 | S 12 | S 12 | — | — | — | — | SW 11 | — | — | — |
— | — | 7 | — | 7 | — | 1 | — | — | 3 | 3 | 3 | 3 | — | — | — | — | 5 | — | — | — | |
Wind waves Height (m) Direction Period (s) | — | N 4 | — | — | — | E 3 | ENE 5 | NE 5 | E 4 | SSE 4 | S 4 | NE 3 | ESE 2 | SSW 7 | — | — | — | SSW 2 | W 4 | SW 4 | W 5 |
— | 2 | — | — | — | 5 | 13 | 11 | 24 | 4 | 9 | 1 | 1 | 125 | — | — | — | 1 | 10 | 22 | 119 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 184 | 287 | 163 | 246 | 249 | 249 | 249 | 249 | 311 | 297 | 184 | 276 | 249 | 51 | 51 | 88 | 259 | 51 | 280 | 276 | 252 |
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.











