
Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 30 Jul 2026:
- Most powerful swell: Friday 31 Jul, 10PM (local time) - 2.5ft (0.7m), 5s period, SW swell with 23 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 0.7m 5s and forecast to arrive on Friday (Jul 31) 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 1.1m 5s period and expected on Wednesday (Aug 05) at 7PM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 10PM (Fri 31st Jul) | 2.5ft (0.7m) 5s |
Table - best surf conditions forecast for Trearddur Bay (Holy Island) over the next 16 days.
The Lowdown
Alright folks, Rusty here. Let’s be straight with you: for the next couple of weeks, Trearddur Bay is looking more like a duck pond than a surf break. We’ve got a long stretch of tiny, weak swells and mostly rubbish wind directions. There’s no standout session in the whole run, so if you’re itching for a paddle, keep your expectations real low.
The water temp is sitting at about 62°, which is a touch warmer than normal for this time of year (about 2° above average), so at least you won’t freeze while you’re sitting there waiting for a wave that’s barely lifting.
Right now, on Thursday the 30th, we’ve got a 2-foot swell out of the WNW with a tiny 4-second period. The combined energy is a measly 14, and it’s cross-shore with a moderate breeze. That’s basically a non-starter. It’s the same story through Friday and Saturday – wind is switching onshore and cross-onshore, and the swell’s too small and weak to bother with.
Sunday the 2nd of August actually offers a bit of a tease: in the morning it’s glassy, with a 1-foot SW swell and that combined energy down to just 3. It’s clean, but there’s barely enough water moving to stand up on. By the afternoon, it goes even flatter.
We then get a few days (Monday the 3rd through Wednesday the 5th) where the wind turns offshore and the conditions look clean on paper, but the swell stays tiny – 0.3 to 1 foot. The combined energy never gets above 10. It’s perfect for a beginner to practice pop-ups on a foamie, maybe, but don’t expect to catch a real ride.
Around the 9th and 10th of August, there’s a little bump. The swell picks up to about 2 feet out of the S/SSW, with period around 6-7 seconds and combined energy climbing into the 30-40 range. Not terrible for Trearddur Bay, but the wind is cross-onshore and fresh, so it’ll be lumpy and choppy. That’s probably your best chance for a wave all fortnight, but it’s still a struggle session, not a standout.
Tuesday the 12th and Wednesday the 13th look poor again, with wind ramping up and swell disappearing. Thursday the 14th into Friday the 15th, we see a tiny 2-foot swell from the WNW with 4-second period and light cross-off winds. Clean lines on the surface, but the swell is so weak and short-period it’ll barely break.
So here’s the bottom line: there is no true standout session over the next 16 days at Trearddur Bay (Holy Island). The swell is basically flat, wind isn’t cooperating, and the forecast is grim. If you’re desperate, the morning of Sunday the 2nd might give you a glassy 1-foot, or the 9th-10th might give you a choppy 2-foot. But don’t hold your breath. It’s a quiet stretch, and that’s just how it goes sometimes.
Rusty.
Short Range ForecastMostly dry. Very mild (max 17°C on Fri afternoon, min 13°C on Thu night). Wind will be generally light. | Days 4-6 Weather SummaryMostly dry. Warm (max 20°C on Mon morning, min 16°C on Sun morning). Winds increasing (calm on Sun morning, fresh winds from the NNE by Mon afternoon). | ||||||||||||||||||||
Thursday 30 | Friday 31 | Saturday 1 | Sunday 2 | Monday 3 | Tuesday 4 | Wednesday 5 | |||||||||||||||
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) | WNW 4 | NW 4 | WSW 3 | W 4 | SW 3 | SSW 5 | SW 5 | SW 5 | SW 4 | SW 4 | W 9 | W 10 | SW 9 | WSW 9 | SW 8 | SW 8 | SW 7 | SW 7 | SW 6 | SW 7 | SSW 7 |
Wave Graph | |||||||||||||||||||||
9 | 3 | 3 | 6 | 8 | 15 | 8 | 3 | 3 | 3 | 2 | 3 | 3 | 8 | 11 | 10 | 9 | 7 | 7 | 7 | 7 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | cross | cross-on | cross-on | on | cross-on | cross-on | on | cross-on | glassy | cross-off | cross-off | cross-off | off | off | off | off | cross-off | glassy | off | cross |
High Tide | 11:54AM5.05m | 00:03AM5.49m | 12:26PM5.10m | 00:36AM5.52m | 12:58PM5.13m | 1:09AM5.52m | 1:32PM5.12m | 1:43AM5.48m | 2:07PM5.09m | 2:20AM5.40m | 2:46PM5.01m | 3:02AM5.25m | 3:31PM4.87m | 3:52AM5.04m | |||||||
Low Tide | 5:50PM1.23m | 6:14AM0.99m | 6:23PM1.15m | 6:46AM0.92m | 6:56PM1.12m | 7:20AM0.89m | 7:31PM1.14m | 7:56AM0.93m | 8:09PM1.21m | 8:35AM1.03m | 8:51PM1.35m | 9:20AM1.21m | 9:40PM1.55m | ||||||||
5:30 | — | — | 5:31 | — | — | 5:33 | — | — | 5:35 | — | — | 5:37 | — | — | 5:37 | — | — | 5:39 | — | — | |
— | — | 9:17 | — | — | 9:15 | — | — | 9:14 | — | — | 9:12 | — | — | 9:10 | — | — | 9:08 | — | — | 9:07 | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 14 | 16 | 16 | 14 | 17 | 17 | 13 | 15 | 15 | 17 | 18 | 17 | 20 | 18 | 19 | 19 | 19 | 16 | 18 | 19 | 18 |
Feels °C | 10 | 13 | 14 | 10 | 13 | 14 | 9 | 11 | 12 | 15 | 15 | 14 | 18 | 13 | 14 | 16 | 15 | 11 | 19 | 19 | 18 |
Swell 1 Height (m) Direction Period (s) | SW 5 | WNW 3 | — | — | WNW 3 | SSW 5 | SW 5 | NW 3 | — | SW 4 | SW 4 | SW 8 | NE 4 | WSW 9 | SW 8 | SW 8 | NE 5 | SW 7 | SW 6 | SW 7 | SSW 7 |
5 | 2 | — | — | 1 | 15 | 6 | 3 | — | 3 | 1 | 3 | 2 | 8 | 11 | 10 | 6 | 7 | 7 | 7 | 4 | |
Swell 2 Height (m) Direction Period (s) | — | N 4 | SW 4 | — | — | — | — | SW 5 | SW 9 | — | W 9 | — | SW 9 | — | N 6 | NNE 4 | SW 7 | NE 4 | NNE 4 | S 13 | SW 13 |
— | 1 | 1 | — | — | — | — | 3 | 3 | — | 2 | — | 3 | — | 1 | 3 | 9 | 3 | 2 | 3 | 7 | |
Swell 3 Height (m) Direction Period (s) | — | SSW 5 | — | — | — | — | — | — | — | — | — | W 10 | — | — | — | NNE 6 | — | — | — | — | SW 13 |
— | 2 | — | — | — | — | — | — | — | — | — | 2 | — | — | — | 3 | — | — | — | — | 7 | |
Wind waves Height (m) Direction Period (s) | WNW 4 | NW 4 | WSW 3 | W 4 | SW 3 | WNW 3 | WNW 4 | — | SW 4 | — | — | NE 3 | ESE 2 | NE 4 | NE 5 | NE 5 | N 4 | — | — | NE 5 | NE 4 |
9 | 3 | 3 | 6 | 8 | 1 | 8 | — | 2 | — | — | 3 | 1 | 15 | 35 | 25 | 1 | — | — | 24 | 29 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 514 | 548 | 246 | 292 | 307 | 380 | 368 | 246 | 246 | 285 | 179 | 155 | 179 | 179 | 184 | 287 | 286 | 287 | 287 | 101 | |
Best forecast wave conditions in Anglesy | |||||||||||||||||||||
Best forecast wave conditions in United Kingdom | |||||||||||||||||||||
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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.











