Surf Forecasts:
Cable Bay (Porth Trecastell) 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 Cable Bay (Porth Trecastell) this week:
The most powerful waves expected at Cable Bay (Porth Trecastell) 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 Cable Bay (Porth Trecastell) over the next 16 days.
The Lowdown
Alright, folks, Rusty here. Let's take a sobering look at what's on the cards. Honestly, the 16-day window for this spot is a tough one. We're looking at a real blank run with nothing worthwhile to paddle out for.
We've got Cable Bay (Porth Trecastell) here, and this stretch is an exposed SW-facing bay, but the whole outlook is a write-off. Straight up, the forecast keeps hitting us with "poor surf conditions" for every single session across the entire period. That's a solid 16 days of... not much. For an exposed spot, a run this quiet is a bit more unusual, but when the forecasts are this stubborn, you just have to sit it out.
The small window around Sunday the 6th and Monday the 7th of September teases a bit of clean, cross-off wind from the NNW, with a faint pulse of south swell at 3 ft. The water temperature anomaly isn't specifically noted here, but with the long stretch of cool, windy weather, you can bet it’s feeling about average for the time of year – maybe a touch chilly on those clean mornings. But that swell is just too weak (combined energy around 23 to 34) and short-period to do anything. Then, by the 9th of September, the wind absolutely hammers the place. We're looking at a massive 12 ft SSW swell hitting on Wednesday the 9th, but it's being blown to bits by 25-31 mph onshore winds. That's a full-on gale, and the energy readings (1152 and 1341) show there's a ton of power, but it's pure chaos. That's kite-surf territory, not paddle-surfing. After that, the swell vanishes into thin air again for the rest of the run. Just a flat, windy mess.
So, there's nothing to recommend. No standouts, no hidden gems. This coast is going to be a write-off for the foreseeable future. Keep the boards in the bag and check back in a week or two. Forecasts can change, and it can't stay this flat forever.
Rusty.
Short Range ForecastModerate rain (total 19mm), heaviest on Sat morning. Very mild (max 18°C on Sat morning, min 15°C on Sat night). Winds increasing (light winds from the NNE on Thu night, fresh winds from the S by Sun afternoon). | Days 4-6 Weather SummaryModerate rain (total 15mm), heaviest on Tue afternoon. Very mild (max 17°C on Mon afternoon, min 13°C on Tue night). Winds decreasing (fresh 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 | cross-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 | 10:23AM3.73m | 10:32PM4.18m | 10:51AM3.84m | 11:00PM4.28m | 11:19AM3.92m | 11:30PM4.30m | 11:49AM3.93m | 00:03AM4.23m | 12:23PM3.87m | 00:40AM4.07m | 1:01PM3.73m | 1:22AM3.82m | 1:47PM3.51m | 2:14AM3.50m | |||||||
Low Tide | 4:45AM0.20m | 4:53PM0.30m | 5:18AM0.06m | 5:26PM0.21m | 5:52AM0.00m | 6:01PM0.20m | 6:27AM0.05m | 6:37PM0.27m | 7:03AM0.19m | 7:16PM0.42m | 7:43AM0.43m | 7:59PM0.63m | 8:28AM0.72m | 8:50PM0.88m | |||||||
6:18 | — | — | 6:20 | — | — | 6:22 | — | — | 6:24 | — | — | 6:26 | — | — | 6:28 | — | — | 6:30 | — | — | |
— | 8:16 | — | — | 8:15 | — | — | 8:13 | — | — | 8:09 | — | — | 8:07 | — | — | 8:06 | — | — | 8:02 | — | |
mm | 3 | — | 1 | 7 | — | 1 | — | 3 | 5 | — | — | 2 | 1 | 7 | — | — | — | 2 | — | 1 | 5 |
Temp °C | 17 | 17 | 17 | 18 | 17 | 15 | 18 | 16 | 15 | 15 | 17 | 17 | 16 | 17 | 16 | 13 | 14 | 17 | 17 | 17 | 18 |
Feels °C | 17 | 15 | 15 | 17 | 14 | 11 | 13 | 11 | 11 | 10 | 13 | 14 | 11 | 14 | 14 | 11 | 10 | 15 | 15 | 10 | 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) | 277 | 282 | 277 | 2 | 326 | 44 | 248 | 286 | 283 | 283 | 297 | 248 | 299 | 506 | 172 | 158 | 261 | 87 | 260 | 256 | 261 |
Best forecast wave conditions in Anglesy | |||||||||||||||||||||
Best forecast wave conditions in United Kingdom | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
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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.











