Surf Forecasts:
Cable Bay (Porth Trecastell) surf forecast from 20 Jul 2026:
- Most powerful swell: Saturday 25 Jul, 7PM (local time) - 2.5ft (0.8m), 4s period, SW swell with 21 kJ wave energy.
Best Forecast Surf Conditions for Cable Bay (Porth Trecastell) this week:
The most powerful waves expected at Cable Bay (Porth Trecastell) in the next 16 days are 0.8m 4s and forecast to arrive on Saturday (Jul 25) at 7PM. Winds are predicted to be onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.5m 6s period and expected on Wednesday (Jul 22) at 7AM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 7PM (Sat 25th Jul) | 2.5ft (0.8m) 4s |
Table - best surf conditions forecast for Cable Bay (Porth Trecastell) over the next 16 days.
The Lowdown
Alright folks, Rusty here. Let’s look at what’s coming up for the next couple of weeks.
Right off the bat, I gotta be straight with you – it’s looking pretty grim for a proper paddle. There’s a big fat gap right at the start with no surf to speak of. From Monday the 20th right through to Thursday the 24th of July, it’s just flat and clean, but flat. The wind’s blowing cross-off from the NNW, keeping the water glassy, but there’s nothing to ride. You’re looking at a solid three or four days of checking the horizon and seeing nothing.
We finally see a tiny pulse of life on Friday the 24th. Cable Bay (Porth Trecastell) picks up a 0.3 ft swell from the south, period of 13 seconds. That’s a long-period groundswell, but it’s just a whisper, with combined swell energy of only (6). The wind is light cross-onshore from the WNW, so it’s not going to be pretty. Honestly, it’s still poor surf conditions.
Saturday the 25th stays poor. The morning is a write-off, and the afternoon brings a bump in wind from the SSW at 15 mph and a 3 ft swell from the SW, but with a terrible period of just 4 seconds. That’s pure wind-chop with combined energy of (22). Not worth the wetsuit.
Sunday the 26th and Monday the 27th are more of the same – tiny, weak swells and messy onshore or cross-onshore winds. The water temperature is sitting at 63°, which is a touch warmer than normal for this time of year, so at least it’s not freezing.
We roll into late July and early August, and it doesn’t get any better. From the 28th through to the 4th of August, the swell barely flickers. We get a few moments of clean conditions on the 30th and 31st with light NNW and E winds, but the swell is a flat 0.7 ft or even zero. There’s a little spike of energy on the 3rd of August with a 1.0 ft swell from the SW and a period of 6 seconds, combined energy (9), but the wind is a fresh 19 mph onshore from the SW, making it a lumpy, choppy mess.
To be fair, there’s just no standout window in this 16-day run. The consistency is completely absent. It’s a tough stretch for Cable Bay, and honestly, with the strong onshore winds and tiny swell, this setup looks more interesting for kite surfing than paddle surfing. Hang in there, folks. Forecasts can change.
Rusty.
Short Range ForecastMostly dry. Very mild (max 18°C on Wed afternoon, min 11°C on Tue night). Wind will be generally light. | Days 5-7 Weather SummaryLight rain (total 9mm), mostly falling on Sat afternoon. Very mild (max 19°C on Thu afternoon, min 14°C on Fri night). Wind will be generally light. | |||||||||||||||||||
Mon 20 | Tuesday 21 | Wednesday 22 | Thursday 23 | Friday 24 | Saturday 25 | Sunday 26 | ||||||||||||||
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) | N 5 | N 6 | N 5 | N 5 | N 7 | NNW 6 | NNW 6 | N 6 | N 5 | N 5 | N 4 | S 13 | S 13 | WSW 2 | S 12 | SW 4 | SW 4 | SW 6 | SSW 5 | SW 5 |
Wave Graph  | ||||||||||||||||||||
 kJ | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 3 | 1 | 3 | 19 | 5 | 5 | 3 | 1 |
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-on | on | cross-off | on | on | cross-off | cross-off | cross | cross-on |
High Tide | 2:51AM3.65m | 3:28PM3.18m | 3:49AM3.33m | 4:30PM3.04m | 4:56AM3.09m | 5:37PM2.97m | 6:08AM2.98m | 6:44PM3.01m | 7:16AM2.99m | 7:44PM3.13m | 8:13AM3.09m | 8:35PM3.31m | ||||||||
Low Tide | 9:06PM0.83m | 9:44AM0.78m | 9:59PM1.11m | 10:38AM1.10m | 11:03PM1.32m | 11:45AM1.31m | 00:23AM1.40m | 1:01PM1.37m | 1:39AM1.32m | 2:06PM1.28m | 2:38AM1.14m | 2:56PM1.10m | 3:23AM0.93m | |||||||
 |  | | |  | | | |  | | | | |  |  |  |  | | | | |
 | — | — | 5:16 | — | — | 5:18 | — | — | 5:18 | — | — | 5:20 | — | — | 5:22 | — | — | 5:24 | — | — |
 | — | 9:31 | — | — | 9:30 | — | — | 9:29 | — | — | 9:28 | — | — | 9:25 | — | — | 9:24 | — | — | 9:22 |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 8 | 1 | — | — | — |
Temp °C | 15 | 15 | 15 | 16 | 13 | 17 | 18 | 16 | 16 | 19 | 18 | 16 | 18 | 18 | 15 | 14 | 15 | 16 | 17 | 16 |
Feels °C | 11 | 13 | 12 | 13 | 11 | 14 | 14 | 13 | 13 | 17 | 17 | 14 | 16 | 16 | 12 | 10 | 14 | 12 | 15 | 12 |
Swell 1 Height (m) Direction Period (s) | — | — | — | N 5 | — | — | — | — | — | — | N 4 | S 13 | WNW 3 | — | S 12 | S 12 | SW 4 | SW 6 | NNW 4 | SW 5 |
| kJ | — | — | — | 15 | — | — | — | — | — | — | 3 | 3 | 1 | — | 3 | 3 | 5 | 5 | 2 | 1 |
Swell 2 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | S 13 | — | — | — | — | SW 6 | — | SSW 5 | — |
| kJ | — | — | — | — | — | — | — | — | — | — | — | 3 | — | — | — | — | 1 | — | 3 | — |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | S 13 | — | — | — | — | — | — | — |
| kJ | — | — | — | — | — | — | — | — | — | — | — | — | 3 | — | — | — | — | — | — | — |
Wind waves Height (m) Direction Period (s) | N 5 | N 6 | N 5 | — | N 7 | NNW 6 | NNW 6 | N 6 | N 5 | N 5 | — | NNW 3 | — | WSW 2 | W 3 | SW 4 | — | NNW 3 | — | NW 3 |
| kJ | 24 | 64 | 24 | — | 171 | 155 | 53 | 77 | 47 | 17 | — | 1 | — | 1 | 3 | 19 | — | 3 | — | 9 |
Nearest Offshore or Glassy | ||||||||||||||||||||
Distance (km) | 574 | 284 | 260 | 352 | 53 | 272 | 302 | 290 | 277 | 294 | 277 | 261 | 262 | 261 | 261 | 604 | 541 | 324 | 541 | 541 |
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)
FREE! Surf-Forecast.com widget for your website
The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Cable Bay (Porth Trecastell) surf forecast. Simply grab the html code snippet that we provide and paste it into your own site. You can choose your preferred language and metric/imperial units for the surf forecast feed to suit users of your site. Click here to get the code.
Information about the Cable Bay (Porth Trecastell) Surf forecast
The above surf forecast table for Cable Bay (Porth Trecastell) provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Cable Bay (Porth Trecastell) can be found by selecting the local surf guide option on the grey menu. Our Cable Bay (Porth Trecastell) 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 (Cable Bay (Porth Trecastell)) 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 Cable Bay (Porth Trecastell) 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 Cable Bay, camping, hotels and holiday cottages in Anglesy, consider staying in Anglesey 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 Holyhead which is 14 km (9 miles) away, Bangor, Porthmadog and Llandudno.
Nearest