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Castlerock Surf Forecast
/ Londonderry (4 surf breaks) /
Surf Forecasts:
Castlerock surfForecast / Londonderry / Ireland
48hr Weather and Surf, issued 6 pm Thursday 21 May 2026 BSTForecast update in hr min s Forecast update imminent
Castlerock surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Castlerock sea temperature is
11.0° C
(Which is normal for this time of year)How big are the waves at Castlerock today?
The current surf forecast for Castlerock at 9PM is: 0.4m 7s primary swell from a Northwest direction and 0.2m 11s secondary swell from a West-northwest direction (forecast issued at 06:00pm May 21). An open ocean swell of 0.2m 2s is not directed at the surf break. The wind direction is predicted to be offshore.
| Time (BST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (21 May) | - | - |
| Afternoon (21 May) | 1.5ft (0.4m) | 7s |
| Evening (21 May) | 1.5ft (0.4m) | 7s |
Table - waves today at Castlerock. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Short Range ForecastLight rain (total 7mm), mostly falling on Thu afternoon. Very mild (max 19°C on Fri afternoon, min 11°C on Fri night). Wind will be generally light. | ||||||||||||||||||||||||
Thu 21 | Friday 22 | Saturday 23 | Sun 24 | |||||||||||||||||||||
4 PM | 7 PM | 10 PM | 1 AM | 4 AM | 7 AM | 10 AM | 1 PM | 4 PM | 7 PM | 10 PM | 1 AM | 4 AM | 7 AM | 10 AM | 1 PM | 4 PM | 7 PM | 10 PM | 1 AM | 4 AM | 7 AM | 10 AM | 1 PM | |
Swell Height Map |    |    |    |    | ||||||||||||||||||||
WNW 11 | NW 7 | W 11 | W 11 | W 11 | W 11 | WNW 11 | W 11 | W 12 | W 12 | W 12 | W 12 | W 12 | WNW 6 | WNW 6 | WNW 6 | WNW 8 | WNW 10 | WNW 10 | WNW 10 | WNW 10 | WNW 10 | WNW 10 | WNW 10 | |
23 | 12 | 9 | 9 | 9 | 10 | 13 | 10 | 11 | 11 | 11 | 10 | 11 | 4 | 4 | 4 | 6 | 9 | 18 | 20 | 36 | 34 | 20 | 19 | |
Wind (km/h) | ||||||||||||||||||||||||
off | off | off | off | off | off | off | off | off | off | cross-off | off | cross-off | off | off | cross-off | cross-off | glassy | off | off | off | off | off | off | |
High Tide | 10:43PM1.68m | 11:02AM1.19m | 11:57PM1.59m | 12:22PM1.09m | 1:22AM1.55m | |||||||||||||||||||
Low Tide | 4:18PM0.33m | 5:43AM0.45m | 5:20PM0.41m | 7:00AM0.52m | 6:30PM0.46m | 8:18AM0.53m | ||||||||||||||||||
 | |  | | |  | | | | |  |  |  |  |  | | | | | | | | | | |
 | — | — | — | — | 5:07 | — | — | — | — | — | — | — | 5:05 | — | — | — | — | — | — | — | 5:05 | — | — | — |
 | — | 9:37 | — | — | — | — | — | — | — | 9:39 | — | — | — | — | — | — | — | 9:42 | — | — | — | — | — | 9:43 |
1 | 3 | — | — | — | — | — | — | — | 1 | 2 | — | — | — | — | — | — | — | — | — | — | — | — | — | |
Temp °C | 18 | 16 | 15 | 14 | 13 | 12 | 14 | 17 | 19 | 17 | 14 | 13 | 12 | 11 | 13 | 17 | 18 | 17 | 16 | 14 | 13 | 12 | 15 | 18 |
16 | 14 | 13 | 10 | 9 | 9 | 11 | 14 | 15 | 14 | 12 | 11 | 9 | 8 | 10 | 13 | 14 | 16 | 14 | 10 | 9 | 9 | 13 | 16 | |
Swell 1 Height (m) Direction Period (s) | NW 7 | NW 7 | NW 7 | NW 7 | WNW 7 | W 11 | ESE 3 | ESE 3 | W 12 | W 12 | ESE 5 | W 12 | W 6 | WNW 6 | WNW 6 | WNW 6 | WNW 8 | WNW 10 | WNW 10 | WNW 10 | WNW 10 | WNW 10 | WNW 10 | WNW 10 |
 kJ | 19 | 12 | 7 | 7 | 4 | 10 | 1 | 1 | 11 | 11 | 3 | 10 | 2 | 4 | 4 | 4 | 6 | 9 | 18 | 20 | 36 | 34 | 20 | 19 |
Swell 2 Height (m) Direction Period (s) | WNW 11 | WNW 11 | W 11 | W 11 | W 11 | WNW 6 | WNW 11 | W 11 | NW 6 | NW 6 | W 12 | E 4 | W 12 | W 10 | W 12 | W 11 | W 11 | — | SE 4 | — | — | — | — | — |
| kJ | 23 | 11 | 9 | 9 | 9 | 4 | 13 | 10 | 2 | 1 | 11 | 1 | 11 | 2 | 3 | 2 | 2 | — | 1 | — | — | — | — | — |
Swell 3 Height (m) Direction Period (s) | — | N 9 | N 9 | N 8 | N 8 | N 8 | NW 6 | NW 6 | NW 6 | E 5 | NW 6 | E 5 | — | W 12 | — | — | — | — | — | — | — | — | — | — |
| kJ | — | 2 | 2 | 1 | 1 | 1 | 2 | 2 | 1 | 1 | 1 | 1 | — | 3 | — | — | — | — | — | — | — | — | — | — |
Wind waves Height (m) Direction Period (s) | — | SSE 3 | — | SE 2 | SE 3 | SE 3 | — | — | SSE 3 | SSE 3 | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| kJ | — | 1 | — | 1 | 1 | 3 | — | — | 1 | 1 | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Nearest Offshore or Glassy | ||||||||||||||||||||||||
Distance (km) | 42 | 42 | 56 | 79 | 67 | 56 | 56 | 40 | 42 | 42 | 42 | 42 | 121 | 40 | 84 | 42 | 42 | 42 | 42 | 40 | 40 | 40 | 42 | 42 |
Best forecast wave conditions in Londonderry | ||||||||||||||||||||||||
Best forecast wave conditions in Ireland | ||||||||||||||||||||||||
Header Global | ||||||||||||||||||||||||
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