
Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 18 Jul 2026:
- Most powerful swell: Saturday 25 Jul, 7AM (local time) - 3.5ft (1.1m), 5s period, NW swell with 47 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 1.1m 5s and forecast to arrive on Saturday (Jul 25) at 7AM. Winds are predicted to be cross-shore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.4m 6s period and expected on Wednesday (Jul 22) at 10AM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 7AM (Sat 25th Jul) | 3.5ft (1.1m) 5s |
Table - best surf conditions forecast for Trearddur Bay (Holy Island) over the next 16 days.
The Lowdown
Alright, Rusty here. Let’s look at what’s happening for the next couple of weeks at Trearddur Bay (Holy Island). Honestly, it’s a tough stretch. We’re looking at a long flat spell from the 20th of July through the 23rd, with absolutely no swell energy. Then a few little pulses show up, but nothing exciting.
The only day that might get you in the water is the 27th of July. Monday morning has a 3ft swell from the WSW, with a combined energy of only 29 (weak). The period is a short 4 seconds, so it’s pretty junky. The wind is cross-shore from the WNW at 12 mph, leaving it a little bumpy, but it’s the best option in a quiet period. The water is a touch warmer than normal, sitting at 62°F.
The rest of the week is a wash. The 30th and 31st of July have clean, offshore winds, but there’s nothing to ride. You’d be looking at a flat, glassy lake. This whole stretch looks more like a kiteboarding setup than a paddle session if anything ever shows up. It’s a tough run, but the forecast can always change.
Rusty.
Short Range ForecastMostly dry. Very mild (max 17°C on Sun afternoon, min 13°C on Sat morning). Wind will be generally light. | Days 4-6 Weather SummaryMostly dry. Very mild (max 18°C on Thu afternoon, min 12°C on Tue night). Wind will be generally light. | ||||||||||||||||||||
Saturday 18 | Sunday 19 | Monday 20 | Tuesday 21 | Wednesday 22 | Thursday 23 | Friday 24 | |||||||||||||||
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) | S 11 | S 11 | S 11 | S 11 | S 10 | S 10 | N 5 | NNW 5 | N 5 | NNW 5 | N 4 | N 6 | NNW 6 | N 6 | N 6 | NNW 5 | W 3 | N 4 | WNW 4 | NW 4 | WNW 4 |
Wave Graph | |||||||||||||||||||||
2 | 2 | 2 | 2 | 2 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 7 | 3 | 25 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross | off | cross-on | on | cross |
High Tide | 2:08PM5.28m | 2:22AM5.60m | 2:52PM5.06m | 3:07AM5.33m | 3:38PM4.82m | 3:53AM5.01m | 4:26PM4.58m | 4:45AM4.69m | 5:23PM4.40m | 5:49AM4.42m | 6:33PM4.31m | 7:10AM4.28m | 7:50PM4.38m | ||||||||
Low Tide | 8:05PM1.00m | 8:41AM0.77m | 8:50PM1.23m | 9:27AM1.09m | 9:37PM1.52m | 10:16AM1.45m | 10:29PM1.82m | 11:11AM1.78m | 11:31PM2.09m | 12:17PM2.03m | 00:48AM2.22m | 1:29PM2.12m | 2:05AM2.17m | ||||||||
5:11 | — | — | 5:13 | — | — | 5:15 | — | — | 5:16 | — | — | 5:18 | — | — | 5:20 | — | — | 5:20 | — | — | |
— | — | 9:35 | — | — | 9:34 | — | — | 9:32 | — | — | 9:30 | — | — | 9:30 | — | — | 9:28 | — | — | 9:27 | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 13 | 16 | 16 | 15 | 17 | 16 | 14 | 16 | 16 | 15 | 17 | 15 | 15 | 16 | 14 | 14 | 18 | 17 | 16 | 18 | 18 |
Feels °C | 9 | 13 | 14 | 11 | 14 | 13 | 11 | 13 | 13 | 12 | 14 | 13 | 11 | 12 | 11 | 11 | 16 | 15 | 12 | 15 | 16 |
Swell 1 Height (m) Direction Period (s) | SW 6 | SW 6 | S 11 | S 11 | S 10 | S 10 | — | — | — | — | — | — | — | — | — | — | N 5 | N 4 | N 4 | NW 4 | SSW 4 |
1 | 1 | 2 | 2 | 2 | 2 | — | — | — | — | — | — | — | — | — | — | 13 | 3 | 1 | 3 | 8 | |
Swell 2 Height (m) Direction Period (s) | S 11 | S 11 | S 5 | — | — | — | — | — | — | — | — | — | — | — | — | — | W 3 | — | S 13 | S 13 | — |
2 | 2 | 1 | — | — | — | — | — | — | — | — | — | — | — | — | — | 1 | — | 3 | 3 | — | |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | |
Wind waves Height (m) Direction Period (s) | N 4 | N 5 | NNW 5 | N 4 | NNW 4 | N 4 | N 5 | NNW 5 | N 5 | NNW 5 | N 4 | N 6 | NNW 6 | N 6 | N 6 | NNW 5 | WNW 3 | — | WNW 4 | SW 3 | WNW 4 |
17 | 59 | 35 | 10 | 5 | 7 | 34 | 26 | 59 | 26 | 14 | 102 | 155 | 88 | 60 | 35 | 1 | — | 7 | 1 | 25 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 284 | 284 | 241 | 284 | 284 | 273 | 284 | 318 | 273 | 306 | 358 | 59 | 350 | 565 | 59 | 267 | 332 | 280 | 285 | 1122 | 326 |
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.










