Surf Forecasts:
Castlerock surf forecast from 20 Aug 2026:
- Best quality surf: Monday 24 Aug, 7AM (local time) - 3.5ft (1.1m), 12s period, NW swell with cross-offshore winds.
- Most powerful swell: Monday 24 Aug, 10AM (local time) - 3.5ft (1.1m), 11s period, NW swell with 315 kJ wave energy.
- Next surfable swell (1★+): Sunday 23 Aug, 10PM (local time) - 2.5ft (0.8m), 10s period with NW swell.
Best Forecast Surf Conditions for Castlerock this week:
The surf forecast for Castlerock over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Sunday (Aug 23) at 10PM. The primary swell is predicted to be 0.8m and 10s period with a secondary swell of 0.4m and 10s. The wind is predicted to be glassy as the swell arrives.
The most powerful waves expected at Castlerock in the next 16 days are 1.1m 11s and forecast to arrive on Monday (Aug 24) at 10AM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.8m 4s period and expected on Tuesday (Aug 25) at 7AM.
| Wave Type | Time (BST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 10PM (Sun 23rd Aug) | 2.5ft (0.8m) 10s |
| Best Surf | 7AM (Mon 24th Aug) | 3.5ft (1.1m) 12s |
| Most Powerful | 10AM (Mon 24th Aug) | 3.5ft (1.1m) 11s |
Table - best surf conditions forecast for Castlerock over the next 16 days.
Short Range ForecastLight rain (total 9mm), mostly falling on Wed night. Very mild (max 15°C on Sat morning, min 12°C on Wed night). Winds increasing (light winds from the N on Wed night, fresh winds from the N by Thu afternoon). | Days 4-6 Weather SummaryMostly dry. Warm (max 20°C on Mon afternoon, min 13°C on Sat night). Winds increasing (calm on Sun morning, fresh winds from the ESE by Tue morning). | ||||||||||||||||||||
Thursday 20 | Friday 21 | Saturday 22 | Sunday 23 | Monday 24 | Tuesday 25 | Wednesday 26 | |||||||||||||||
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) | NNW 8 | NNW 7 | NNW 7 | NNW 6 | NNW 6 | NNW 5 | NNW 5 | NW 5 | NW 6 | NW 6 | NW 7 | NW 10 | NW 11 | NW 11 | WNW 10 | NW 11 | NW 10 | E 5 | NW 12 | WNW 11 | WNW 10 |
Wave Graph  | |||||||||||||||||||||
 kJ | 183 | 285 | 239 | 126 | 69 | 46 | 13 | 10 | 16 | 31 | 37 | 124 | 315 | 187 | 65 | 19 | 15 | 34 | 5 | 22 | 32 |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | on | on | on | on | on | on | cross-on | cross-on | cross-off | cross-off | on | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off |
High Tide | 11:24AM1.21m | 11:54PM1.10m | 1:03PM1.11m | 2:29AM1.01m | 3:46PM1.16m | 4:16AM1.09m | 4:48PM1.29m | 4:59AM1.20m | 5:25PM1.44m | 5:30AM1.32m | 5:55PM1.59m | 5:58AM1.43m | 6:23PM1.72m | ||||||||
Low Tide | 5:35AM0.63m | 6:11PM0.68m | 6:42AM0.72m | 8:03PM0.77m | 8:39AM0.74m | 10:15PM0.72m | 10:18AM0.64m | 11:16PM0.61m | 11:10AM0.50m | 11:53PM0.49m | 11:46AM0.35m | 00:25AM0.38m | 12:17PM0.22m | 00:54AM0.29m | |||||||
 |  |  | | |  | | | |  | |  | | | | | | | | | | |
 | 6:09 | — | — | 6:11 | — | — | 6:13 | — | — | 6:13 | — | — | 6:16 | — | — | 6:18 | — | — | 6:20 | — | — |
 | — | 8:50 | — | — | 8:47 | — | — | 8:45 | — | — | 8:43 | — | — | 8:40 | — | — | 8:37 | — | — | 8:36 | — |
mm | 2 | — | 1 | 1 | — | — | — | — | — | — | — | — | — | — | — | — | — | 1 | — | — | 3 |
Temp °C | 14 | 14 | 13 | 13 | 13 | 13 | 15 | 15 | 13 | 15 | 15 | 13 | 18 | 20 | 16 | 17 | 18 | 16 | 19 | 21 | 17 |
Feels °C | 8 | 7 | 6 | 8 | 8 | 8 | 12 | 11 | 11 | 14 | 13 | 12 | 16 | 16 | 13 | 10 | 12 | 10 | 16 | 18 | 15 |
Swell 1 Height (m) Direction Period (s) | NNW 8 | WNW 9 | WNW 9 | NW 8 | WNW 8 | W 7 | W 7 | W 7 | NW 6 | NW 6 | NW 7 | NW 10 | NW 11 | NW 11 | WNW 10 | WNW 10 | NW 10 | N 10 | ENE 4 | WNW 11 | WNW 10 |
| kJ | 183 | 17 | 15 | 3 | 6 | 1 | 1 | 1 | 16 | 31 | 37 | 124 | 315 | 187 | 65 | 18 | 15 | 2 | 12 | 22 | 32 |
Swell 2 Height (m) Direction Period (s) | WNW 10 | — | — | — | — | — | W 8 | W 10 | NW 10 | NW 9 | N 12 | — | — | — | NNW 12 | NW 11 | WNW 10 | NW 9 | NW 12 | ENE 4 | N 5 |
| kJ | 33 | — | — | — | — | — | 1 | 2 | 4 | 3 | 3 | — | — | — | 15 | 19 | 9 | 3 | 5 | 3 | 2 |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | W 7 | — | — | — | — | — | — | — | — | N 10 | W 9 | N 9 | N 4 | — |
| kJ | — | — | — | — | — | — | — | 1 | — | — | — | — | — | — | — | — | 2 | 1 | 2 | 2 | — |
Wind waves Height (m) Direction Period (s) | ENE 3 | NNW 7 | NNW 7 | NNW 6 | NNW 6 | NNW 5 | NNW 5 | NW 5 | — | — | — | — | — | ESE 3 | ESE 2 | ESE 4 | E 4 | E 5 | — | — | — |
| kJ | 1 | 285 | 239 | 126 | 69 | 46 | 13 | 10 | — | — | — | — | — | 1 | 1 | 15 | 9 | 34 | — | — | — |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 342 | 751 | 282 | 411 | 266 | 266 | 254 | 282 | 44 | 27 | 42 | 0 | 0 | 2 | 40 | 212 | 336 | 212 | 40 | 40 | 16 |
Best forecast wave conditions in Londonderry | |||||||||||||||||||||
Best forecast wave conditions in Ireland | |||||||||||||||||||||
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 Castlerock 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 Castlerock Surf forecast
The above surf forecast table for Castlerock provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Castlerock can be found by selecting the local surf guide option on the grey menu. Our Castlerock 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 (Castlerock) 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 Castlerock 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 Londonderry? If you are looking for accommodation near Castlerock, camping, hotels and holiday cottages in Londonderry, consider staying in Coleraine which is 8 km (5 miles) away. Other places in and around Londonderry where you can find information about places to rent, and car hire include Ballycastle which is 34 km (21 miles) away, Ballypatrick, Londonderry County Borough and Derry.
Nearest