
Surf Forecasts:
Cable Bay (Porth Trecastell) surf forecast from 30 Jul 2026:
- Most powerful swell: Saturday 1 Aug, 4AM (local time) - 2.5ft (0.7m), 4s period, NW swell with 16 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 0.7m 4s and forecast to arrive on Saturday (Aug 01) at 4AM. Winds are predicted to be cross-shore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.9m 4s period and expected on Tuesday (Aug 04) at 7PM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 4AM (Sat 1st Aug) | 2.5ft (0.7m) 4s |
Table - best surf conditions forecast for Cable Bay (Porth Trecastell) over the next 16 days.
The Lowdown
Alright, it’s your boy Rusty here. I’ve looked over the charts for the next couple of weeks, and I’ve got to be straight with you—it’s a grim stretch ahead for Cable Bay (Porth Trecastrell). The swell window is just not cooperating, and the model is showing next to nothing for the entire 16-day period. We’re looking at a long, painful gap with no real surf on offer.
The water is sitting at about 62°, which is a touch warmer than normal for this time of year, so it’s not freezing, but you won’t be needing a spring suit for waves that aren’t there.
The first few days are a write-off. Thursday the 30th sees a tiny 1ft northwest windswell with a shocking 4-second period and a light cross breeze. The combined energy is a paltry 5 (weak). It’s just bumpy, weak, and useless. Friday and Saturday are the same story: a little more wind, a little more chop, but still nothing to paddle for. The swell stays below 2ft until we hit the second week of August.
Sunday the 2nd offers a tease—clean conditions with glassy or light offshore winds, but the swell is laughable at 0.3ft to 1ft. The energy is only 2 to 3 (weak). That’s a lake, not a surf break. The same holds for Monday and Tuesday the 4th, where we get some glassy conditions but still only 1ft on a long 8-second period, with combined energy hitting 10 (weak). It’s clean, but you’d be bobbing around on a millpond.
The first real blip of interest comes on Saturday the 8th. The morning brings a 3ft swell from the SSW with a 6-second period, and the combined energy jumps to 90 (moderate). The wind is a clean cross-offshore from the north at 9 mph. This is surfable, but very ordinary. The afternoon sees the swell bump to 6ft (still too small for that period to hold shape) and energy hits 216 (moderate). The wind stays clean, but the period is still short, so it’ll be a bit fat and lumpy. It’s not a standout, but it’s the only time in the whole window where you might get a fun little wave if you’re desperate.
Sunday the 9th morning offers 4ft with a 7-second period and energy of 136 (moderate), but the wind is a stiff 12 mph cross-offshore. It’s clean, but the swell is weak and won’t hold up well.
After that, it’s back to near-zero for the rest of the period. The 10th and 11th are glassy or clean but tiny, with swells under 1ft and energy in the single digits. The last few days of the 14th and 15th are just as flat, with a 0.3ft swell and 2 to 4 (weak) energy.
Honestly, the only day that’s even worth a look is Saturday the 8th. The morning is your best bet, with clean 3ft waves and a bit of push. It’s not going to be epic, but it beats the rest of the fortnight. For the rest, you’re better off waxing your board and waiting for a change in the charts.
Rusty.
Short Range ForecastMostly dry. Very mild (max 18°C on Sun morning, min 13°C on Thu night). Wind will be generally light. | Days 5-7 Weather SummaryMostly dry. Warm (max 22°C on Mon afternoon, min 16°C on Sun night). Wind will be generally light. | |||||||||||||||||||
Thu 30 | Friday 31 | Saturday 1 | Sunday 2 | Monday 3 | Tuesday 4 | Wednesday 5 | ||||||||||||||
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) | NW 4 | WSW 3 | W 4 | SW 3 | SSW 5 | WNW 4 | W 4 | SW 3 | SW 4 | W 9 | SW 8 | SW 9 | SW 9 | SW 8 | SW 8 | SW 8 | SSW 7 | SW 7 | SSW 7 | SW 6 |
Wave Graph | ||||||||||||||||||||
3 | 3 | 7 | 3 | 15 | 10 | 7 | 3 | 2 | 2 | 3 | 3 | 3 | 11 | 10 | 9 | 5 | 7 | 4 | 7 | |
Wind (km/h) | ||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | cross-on | cross-on | on | cross-on | cross-on | on | cross-on | off | cross-off | off | cross-off | off | cross-off | glassy | glassy | on | cross-on | on | cross |
High Tide | 11:01PM4.02m | 11:19AM3.63m | 11:31PM4.09m | 11:49AM3.65m | 00:00AM4.10m | 12:20PM3.64m | 00:32AM4.05m | 12:54PM3.59m | 1:07AM3.94m | 1:32PM3.51m | 1:48AM3.77m | 2:18PM3.37m | 2:39AM3.55m | |||||||
Low Tide | 5:20PM0.43m | 5:48AM0.25m | 5:54PM0.38m | 6:22AM0.21m | 6:28PM0.40m | 6:57AM0.24m | 7:04PM0.48m | 7:33AM0.34m | 7:41PM0.62m | 8:12AM0.50m | 8:22PM0.79m | 8:55AM0.70m | 9:10PM0.99m | |||||||
— | — | 5:31 | — | — | 5:33 | — | — | 5:35 | — | — | 5:37 | — | — | 5:37 | — | — | 5:39 | — | — | |
— | 9:16 | — | — | 9:15 | — | — | 9:13 | — | — | 9:12 | — | — | 9:09 | — | — | 9:07 | — | — | 9:06 | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 16 | 16 | 14 | 17 | 16 | 13 | 15 | 15 | 18 | 18 | 18 | 20 | 22 | 21 | 20 | 21 | 20 | 18 | 20 | 18 |
Feels °C | 13 | 14 | 11 | 13 | 13 | 9 | 13 | 12 | 17 | 17 | 15 | 16 | 17 | 16 | 19 | 19 | 19 | 17 | 18 | 18 |
Swell 1 Height (m) Direction Period (s) | NW 4 | — | — | WNW 3 | SSW 5 | SW 5 | NW 4 | — | SW 4 | SW 4 | SW 8 | NNE 3 | SW 9 | SW 8 | SW 8 | SW 8 | NE 5 | NE 4 | SSW 7 | SW 6 |
3 | — | — | 1 | 15 | 6 | 5 | — | 2 | 1 | 3 | 1 | 3 | 11 | 10 | 9 | 14 | 3 | 4 | 7 | |
Swell 2 Height (m) Direction Period (s) | SSW 5 | — | — | — | — | — | SW 5 | — | — | W 9 | — | SW 9 | — | — | NE 5 | — | SSW 7 | SW 7 | NNE 4 | — |
2 | — | — | — | — | — | 3 | — | — | 2 | — | 3 | — | — | 1 | — | 5 | 7 | 1 | — | |
Swell 3 Height (m) Direction Period (s) | N 4 | — | — | — | — | — | — | W 9 | — | — | — | — | — | — | — | — | — | — | S 13 | SW 13 |
1 | — | — | — | — | — | — | 2 | — | — | — | — | — | — | — | — | — | — | 3 | 7 | |
Wind waves Height (m) Direction Period (s) | — | WSW 3 | W 4 | SW 3 | WNW 3 | WNW 4 | W 4 | SW 3 | — | — | NE 3 | ESE 2 | NE 4 | NE 4 | ENE 5 | NE 5 | — | — | — | — |
— | 3 | 7 | 3 | 6 | 10 | 7 | 3 | — | — | 2 | 1 | 2 | 9 | 14 | 17 | — | — | — | — | |
Nearest Offshore or Glassy | ||||||||||||||||||||
Distance (km) | 580 | 256 | 302 | 579 | 287 | 412 | 363 | 256 | 256 | 295 | 158 | 172 | 172 | 158 | 233 | 297 | 313 | 297 | 287 | 279 |
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.











