
Surf Forecasts:
Cable Bay (Porth Trecastell) surf forecast from 18 Jul 2026:
- Most powerful swell: Saturday 25 Jul, 7AM (local time) - 2ft (0.6m), 4s period, W swell with 10 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 0.6m 4s and forecast to arrive on Saturday (Jul 25) at 7AM. 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 1PM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 7AM (Sat 25th Jul) | 2ft (0.6m) 4s |
Table - best surf conditions forecast for Cable Bay (Porth Trecastell) over the next 16 days.
The Lowdown
Alright folks, Rusty here. Let’s be straight with you – this outlook for the next couple of weeks is a tough one to write. We’re looking at a long, dry spell with almost nothing on offer for a solid stretch.
The first bit of the period, starting Friday the 17th, is a non-starter. We’ve got a tiny 0.3ft swell rolling in from the SW with a long 12-second period, but it’s just not enough to get excited about. The combined energy is a measly 10, and the water is sitting at 63°, which is much warmer than normal for this time of year. The wind is a cross-off from the NNW, so conditions are clean, but there’s simply no wave to ride. This flat spell continues for days.
From Saturday the 18th all the way through to Thursday the 24th, it’s a complete brick. The combined energy readings are mostly zeros or single digits. The wind stays clean for much of it, but without any swell, it’s a waste. There’s a gap of about seven days here with no surf recommendations whatsoever.
We start to see a tiny pulse on Saturday the 25th of July, with a 3ft swell from the WNW, but the period is a short, weak 4 seconds. The combined energy is only 25, and it’s a cross-onshore wind, making for bumpy, choppy conditions. Not worth the paddle.
The only real chance of anything surfable comes on Monday the 27th of July. We’ve got a 4ft swell from the west, with a period of 5 seconds and combined energy hitting 88. That’s the biggest energy we’ll see in the whole window. But here’s the kicker: the wind is a moderate cross-onshore, and the surf quality is still rated as poor. For a spot like Cable Bay (Porth Trecastell), which is an exposed SW-facing beach, this setup looks more interesting for the kite surfers than it does for us paddle surfers. The swell is too short-period and messy to be any good for a proper wave.
After that, it fizzles back into tiny, weak swell and clean but empty conditions through the end of July and into the first of August.
Bottom line: There’s not a single standout session in this 16-day window. The best you can hope for is a choppy, wind-affected 4ft wave on the 27th, but don’t expect much. It’s a flat spell that’s more normal for the area than we’d like. Keep your gear ready – forecasts can change, but right now, it’s looking grim.
Rusty.
Short Range ForecastMostly dry. Very mild (max 18°C on Fri night, min 12°C on Sun night). Wind will be generally light. | Days 4-6 Weather SummaryMostly dry. Very mild (max 17°C on Tue afternoon, min 11°C on Tue night). Mainly fresh winds. | ||||||||||||||||||||
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 | SW 11 | S 11 | S 11 | S 10 | S 10 | NNW 5 | NNW 5 | NNW 5 | NNW 5 | N 5 | N 6 | NNW 6 | NNW 6 | N 6 | NNW 6 | N 5 | NNW 5 | S 13 | S 13 | SW 3 |
Wave Graph | |||||||||||||||||||||
2 | 5 | 2 | 2 | 2 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 3 | 3 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | cross-off | cross | 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 | off | on | on | cross-on |
High Tide | 12:58PM3.76m | 1:12AM4.25m | 1:45PM3.57m | 2:00AM3.97m | 2:34PM3.37m | 2:51AM3.65m | 3:28PM3.18m | 3:49AM3.33m | 4:30PM3.04m | 4:56AM3.09m | 5:37PM2.97m | 6:08AM2.98m | 6:44PM3.01m | ||||||||
Low Tide | 7:25AM-0.16m | 7:35PM0.30m | 8:10AM0.10m | 8:19PM0.55m | 8:56AM0.43m | 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 | |||||||
5:11 | — | — | 5:13 | — | — | 5:15 | — | — | 5:16 | — | — | 5:18 | — | — | 5:18 | — | — | 5:20 | — | — | |
— | — | 9:34 | — | — | 9:32 | — | — | 9:31 | — | — | 9:30 | — | — | 9:29 | — | — | 9:28 | — | — | 9:25 | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 7 |
Temp °C | 14 | 17 | 17 | 15 | 16 | 16 | 14 | 17 | 16 | 16 | 17 | 14 | 16 | 16 | 14 | 16 | 17 | 16 | 17 | 18 | 17 |
Feels °C | 9 | 13 | 15 | 13 | 13 | 13 | 10 | 14 | 14 | 13 | 15 | 12 | 12 | 11 | 10 | 13 | 15 | 14 | 15 | 16 | 14 |
Swell 1 Height (m) Direction Period (s) | SW 6 | SW 6 | S 11 | S 11 | S 10 | S 10 | — | — | — | — | — | — | — | — | — | — | N 5 | NNW 5 | N 4 | — | — |
1 | 1 | 2 | 2 | 2 | 2 | — | — | — | — | — | — | — | — | — | — | 18 | 7 | 1 | — | — | |
Swell 2 Height (m) Direction Period (s) | S 11 | SW 11 | S 5 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | S 13 | S 13 | — |
2 | 5 | 1 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 3 | 3 | — | |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | |
Wind waves Height (m) Direction Period (s) | NNW 5 | NNW 6 | N 5 | NNW 4 | NNW 4 | N 4 | NNW 5 | NNW 5 | NNW 5 | NNW 5 | N 5 | N 6 | NNW 6 | NNW 6 | N 6 | NNW 6 | — | — | — | SW 2 | SW 3 |
46 | 104 | 11 | 5 | 5 | 10 | 47 | 33 | 45 | 32 | 15 | 106 | 130 | 150 | 85 | 50 | — | — | — | 1 | 3 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 284 | 284 | 260 | 284 | 332 | 272 | 284 | 325 | 272 | 283 | 352 | 53 | 53 | 53 | 53 | 260 | 302 | 272 | 261 | 244 | 261 |
Best forecast wave conditions in Anglesy | |||||||||||||||||||||
Best forecast wave conditions in United Kingdom | |||||||||||||||||||||
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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.










