
Surf Forecasts:
Trearddur Bay (Holy Island) surf forecast from 12 Jul 2026:
- Most powerful swell: Saturday 18 Jul, 4AM (local time) - 2.5ft (0.8m), 7s period, SSW swell with 56 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 0.8m 7s and forecast to arrive on Saturday (Jul 18) at 4AM. Winds are predicted to be offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.1m 5s period and expected on Tuesday (Jul 14) at 10PM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 4AM (Sat 18th Jul) | 2.5ft (0.8m) 7s |
Table - best surf conditions forecast for Trearddur Bay (Holy Island) over the next 16 days.
Alright folks, Rusty here. Let’s get into it. Usually, I’d be buzzing to talk about a solid run of swell, but this time around, I have to be straight with you. For the next 16 days, Trearddur Bay is looking like a ghost town for surf. The entire period is a wipeout.
We start now and it’s flat. The first few days are a total write-off. There’s just nothing coming in. You’ll see a few tiny ripples around the 11th of July, but with swell heights barely reaching 0.7 ft and combined energy sitting at a pitiful 4, it’s not worth wetting a wetsuit. The wind is offshore, which is a tease, but the ocean just isn’t cooperating.
The pattern continues through the middle of the week. We get a slight bump around the 17th and 18th of July, with swell heights nudging up to 2 ft from the SW, but the period is a short, weak 6 seconds. The combined energy barely cracks 40 – that’s just a weak puff of energy. The wind is cross-off, which keeps the surface tidy, but there’s no power behind it. It’s the kind of surf that makes you paddle out and just sit there.
Then, around the 21st of July, we see the biggest swell of the whole window. On Tuesday morning, the swell hits 4 ft from the west with a combined energy of 66. That’s still in the weak category. The wind is cross-shore, so it’s a bit bumpy. The next day, the 22nd of July, the swell pumps up to 6 ft from the WSW (moderate energy at 161), but the wind swings onshore, turning it into a lumpy, choppy mess. For a beginner-friendly spot like Trearddur Bay, that’s just messy. You’d be better off looking at it for a kite session than a paddle session.
After that, it’s back to the bare minimum. The water temp is sitting at 61° – a touch warmer than normal for the time of year, which is a nice perk for your feet, but that’s about the only good news.
To be brutally honest, there is not a single standout session in these 16 days. The forecast is as dry as a bone. If you’re desperate for a paddle, the morning of the 21st of July might give you a tiny, crumbly wave, but don’t hold your breath. For an area that can be fairly consistent, this is a rough patch. Forecasts can change, but right now, save your energy and wax.
Rusty.
Short Range ForecastMostly dry. Warm (max 24°C on Sun afternoon, min 14°C on Sun night). Mainly fresh winds. | Days 4-6 Weather SummarySome drizzle, heaviest during Wed night. Warm (max 24°C on Wed afternoon, min 18°C on Wed morning). Wind will be generally light. | ||||||||||||||||||||
Sunday 12 | Monday 13 | Tuesday 14 | Wednesday 15 | Thursday 16 | Friday 17 | Saturday 18 | |||||||||||||||
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) | NE 5 | NE 4 | NE 5 | SE 4 | S 19 | S 15 | S 18 | SW 18 | SW 14 | SW 16 | SW 16 | S 16 | SSW 6 | SW 14 | SW 8 | SSW 7 | SSW 7 | SSW 7 | SW 6 | SW 6 | SW 6 |
Wave Graph | |||||||||||||||||||||
0 | 0 | 0 | 1 | 7 | 4 | 6 | 12 | 7 | 10 | 10 | 5 | 4 | 8 | 14 | 19 | 19 | 41 | 38 | 17 | 8 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | off | cross-off | off | off | off | off | off | cross-off | off | off | cross-off | off | off | cross-on | off | cross-off | off | cross-off | cross-off | cross-off |
High Tide | 9:34PM5.14m | 10:03AM5.23m | 10:28PM5.42m | 10:57AM5.41m | 11:18PM5.67m | 11:48AM5.52m | 00:06AM5.82m | 12:36PM5.53m | 00:52AM5.87m | 1:23PM5.44m | 1:37AM5.79m | 2:08PM5.28m | 2:22AM5.60m | ||||||||
Low Tide | 3:11PM1.28m | 3:45AM1.10m | 4:08PM1.09m | 4:40AM0.77m | 4:59PM0.91m | 5:31AM0.52m | 5:47PM0.80m | 6:20AM0.38m | 6:34PM0.77m | 7:08AM0.38m | 7:20PM0.84m | 7:55AM0.51m | 8:05PM1.00m | ||||||||
5:05 | — | — | 5:05 | — | — | 5:07 | — | — | 5:07 | — | — | 5:09 | — | — | 5:11 | — | — | 5:11 | — | — | |
— | — | 9:42 | — | — | 9:40 | — | — | 9:39 | — | — | 9:38 | — | — | 9:37 | — | — | 9:36 | — | — | 9:35 | |
mm | — | — | — | — | — | — | — | — | — | — | — | 1 | — | — | — | — | — | — | — | — | — |
Temp °C | 23 | 24 | 23 | 18 | 20 | 19 | 20 | 24 | 22 | 22 | 24 | 24 | 23 | 23 | 18 | 20 | 21 | 19 | 20 | 20 | 19 |
Feels °C | 19 | 19 | 18 | 11 | 14 | 12 | 15 | 18 | 15 | 19 | 19 | 21 | 23 | 22 | 17 | 18 | 19 | 17 | 18 | 17 | 17 |
Swell 1 Height (m) Direction Period (s) | — | — | — | — | S 19 | S 15 | S 18 | SW 18 | S 7 | S 6 | SW 8 | SSW 7 | N 5 | NNE 4 | SW 8 | SSW 7 | SSW 7 | SW 12 | SW 6 | SW 6 | NNW 5 |
— | — | — | — | 7 | 4 | 6 | 12 | 1 | 1 | 2 | 4 | 5 | 4 | 14 | 19 | 19 | 6 | 38 | 17 | 9 | |
Swell 2 Height (m) Direction Period (s) | — | — | — | SE 4 | — | — | — | — | SW 14 | SW 16 | SW 16 | S 13 | NE 4 | SSW 6 | N 4 | — | SW 12 | SW 13 | S 11 | S 11 | SW 6 |
— | — | — | 1 | — | — | — | — | 7 | 10 | 10 | 3 | 3 | 3 | 1 | — | 6 | 6 | 2 | 2 | 8 | |
Swell 3 Height (m) Direction Period (s) | NE 5 | — | — | — | — | — | W 18 | — | — | S 13 | S 13 | S 16 | SSW 6 | SW 14 | SW 6 | — | — | — | — | — | SW 11 |
1 | — | — | — | — | — | 6 | — | — | 3 | 3 | 5 | 4 | 8 | 1 | — | — | — | — | — | 5 | |
Wind waves Height (m) Direction Period (s) | NE 5 | NE 4 | NE 5 | NE 4 | NNE 4 | NE 4 | NE 4 | NNE 4 | NE 5 | NE 5 | NE 4 | NE 5 | — | — | — | S 3 | SSW 4 | SSW 7 | NNW 4 | NW 4 | — |
17 | 31 | 25 | 23 | 32 | 18 | 21 | 30 | 30 | 22 | 27 | 21 | — | — | — | 6 | 6 | 41 | 6 | 4 | — | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 287 | 303 | 305 | 415 | 307 | 286 | 184 | 163 | 288 | 306 | 208 | 101 | 314 | 163 | 184 | 155 | 161 | 8 | 51 | 575 | 278 |
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.










