Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 28 Aug 2026:
- Most powerful swell: Thursday 3 Sep, 1AM (local time) - 6.5ft (2.0m), 6s period, SW swell with 301 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 2.0m 6s and forecast to arrive on Thursday (Sep 03) at 1AM. Winds are predicted to be cross-onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.7m 5s period and expected on Sunday (Aug 30) at 4AM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 1AM (Thu 3rd Sep) | 6.5ft (2.0m) 6s |
Table - best surf conditions forecast for Trearddur Bay (Holy Island) over the next 16 days.
The Lowdown
Right then, let’s have a look at what’s on offer for Trearddur Bay (Holy Island). I’ll be straight with you, it’s a tough read for the next couple of weeks. The swell is small and the wind is all over the place, so we’re looking at a long stretch of pretty ordinary conditions. There’s not a single session that’s worth paddling out for—every single one in the 16-day window is rated as poor surf. That’s a big gap with no real recommendations, and for this area, a blank run like this is more normal when the patterns aren’t lining up.
Over the first few days, into the end of August and the start of September, we’re dealing with tiny swell—mostly around 1 ft to 4 ft—but the wind is a problem. Friday the 28th has a bit of cross-shore breeze but only 1 ft from the SSW with a short 6-second period, and the combined wave energy is weak at just 19. Saturday the 29th morning shows a slightly better 3 ft with a cross-offshore wind, which is clean, but the swell is still small and gutless. The energy is still low at 67. By Saturday afternoon, the onshore wind kicks in at 16 mph and the swell jumps to 4 ft, but it’s blown out and messy.
Moving into Sunday and Monday, it gets worse. Sunday has strong onshore winds up to 25 mph with a short 5-second period, and Monday has a 5 ft WNW swell but with a fresh cross-shore wind that brings lumpy cross-chop. The energy on Monday morning is moderate at 223, but the quality is still poor.
Later in the week, things actually get bigger, but it’s no good for surfing. On Wednesday the 9th of September, we see a big jump to 12 ft from the SSW with a 7-second period, and the combined energy is a massive 1152—that’s very strong. But the wind is howling from the south at 28 mph, making it a strong cross-onshore mess. That kind of setup, with big, short-period swell and strong wind blowing across the beach break, is more interesting for kite surfing than for paddle surfing. It’s way too big for beginners at over 8 ft, and even for experts, the wind and chop will make it ugly. It blows out completely on the Wednesday afternoon with near-gale winds at 34 mph and energy at 1341.
The second week trails off into tiny, weak swell again, with the odd clean session on the 7th and 8th of September—3 ft with cross-offshore winds—but the period is short at 4 seconds and the energy is low at 34 and 31. Not worth the rubber.
We’ve got no standout sessions. The water temperature anomaly isn’t given, but it’s not mentioned, so I’ll say it’s about average for the time of year. Trearddur Bay itself is a fairly exposed spot, and it’s inconsistent, so when it’s off, it’s really off.
Keep an eye on the charts, but for now, I’d save the wax for another time.
Rusty
Short Range ForecastHeavy rain (total 21mm), heaviest during Sat morning. Very mild (max 18°C on Sun morning, min 15°C on Sat night). Winds increasing (calm on Thu night, fresh winds from the S by Sun afternoon). | Days 4-6 Weather SummaryModerate rain (total 13mm), heaviest on Tue afternoon. Very mild (max 17°C on Mon afternoon, min 13°C on Tue night). Winds decreasing (strong winds from the WNW on Sun night, light winds from the NW by Wed morning). | ||||||||||||||||||||
Friday 28 | Saturday 29 | Sunday 30 | Monday 31 | Tuesday 1 | Wednesday 2 | Thursday 3 | |||||||||||||||
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) | SSW 6 | SSW 6 | SSW 6 | SSW 6 | SSW 6 | SW 9 | SSW 8 | SSW 5 | SSW 7 | SW 8 | SW 7 | SW 7 | SW 4 | SW 5 | SW 6 | SW 6 | SSW 3 | SW 6 | SW 7 | SW 7 | SW 6 |
Wave Graph | |||||||||||||||||||||
16 | 16 | 56 | 62 | 145 | 182 | 92 | 64 | 131 | 102 | 44 | 37 | 28 | 42 | 33 | 8 | 10 | 301 | 124 | 85 | 46 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | on | on | cross-off | on | cross-on | cross-on | cross-on | cross-on | cross | on | on | on | cross-on | cross | cross | on | cross-on | on | on | cross-on |
High Tide | 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 | 2:15PM5.23m | 2:36AM5.34m | 3:01PM5.01m | 3:30AM5.02m | |||||||
Low Tide | 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 | 8:06AM0.98m | 8:25PM1.22m | 8:51AM1.28m | 9:16PM1.51m | |||||||
6:20 | — | — | 6:20 | — | — | 6:22 | — | — | 6:24 | — | — | 6:26 | — | — | 6:28 | — | — | 6:30 | — | — | |
— | 8:17 | — | — | 8:15 | — | — | 8:13 | — | — | 8:10 | — | — | 8:08 | — | — | 8:06 | — | — | 8:04 | — | |
mm | 3 | — | 1 | 9 | — | 1 | 1 | 3 | 4 | — | — | 2 | 1 | 6 | — | — | — | 2 | — | — | 4 |
Temp °C | 16 | 17 | 17 | 17 | 17 | 15 | 18 | 16 | 15 | 15 | 17 | 17 | 16 | 17 | 16 | 13 | 14 | 17 | 17 | 18 | 18 |
Feels °C | 15 | 15 | 14 | 16 | 14 | 11 | 13 | 10 | 11 | 10 | 12 | 14 | 10 | 13 | 12 | 10 | 9 | 14 | 14 | 12 | 14 |
Swell 1 Height (m) Direction Period (s) | SSW 6 | SSW 6 | SSW 6 | SSW 6 | — | SW 9 | WNW 4 | — | SSW 7 | SW 8 | NW 5 | N 4 | WNW 4 | — | SW 6 | SW 6 | — | — | SW 14 | NW 4 | SW 14 |
16 | 16 | 56 | 62 | — | 182 | 3 | — | 131 | 84 | 25 | 1 | 1 | — | 33 | 8 | — | — | 8 | 4 | 8 | |
Swell 2 Height (m) Direction Period (s) | S 12 | N 4 | — | — | — | — | N 4 | — | SW 11 | SW 9 | SW 7 | N 4 | — | — | — | N 4 | SW 16 | — | — | SW 14 | SW 9 |
3 | 2 | — | — | — | — | 1 | — | 20 | 37 | 44 | 1 | — | — | — | 3 | 10 | — | — | 8 | 3 | |
Swell 3 Height (m) Direction Period (s) | — | S 11 | S 11 | — | — | — | — | — | — | — | — | — | — | — | — | S 16 | — | — | — | — | — |
— | 3 | 2 | — | — | — | — | — | — | — | — | — | — | — | — | 5 | — | — | — | — | — | |
Wind waves Height (m) Direction Period (s) | NW 3 | — | — | SE 3 | SSW 6 | NW 5 | SSW 8 | SSW 5 | — | WNW 5 | — | SW 7 | SW 4 | SW 5 | N 3 | — | SSW 3 | SW 6 | SW 7 | SW 7 | SW 6 |
2 | — | — | 5 | 145 | 68 | 92 | 64 | — | 102 | — | 37 | 28 | 42 | 2 | — | 10 | 301 | 124 | 85 | 46 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 280 | 283 | 280 | 8 | 316 | 51 | 255 | 285 | 284 | 280 | 307 | 255 | 305 | 514 | 179 | 163 | 251 | 96 | 250 | 246 | 251 |
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.











