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Castlerock Surf Forecast
/ Londonderry (4 surf breaks) /
Surf Forecasts:
Castlerock surfForecast / Londonderry / Ireland
48hr Weather and Surf, issued 12 am 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
10.7° C
(Which is normal for this time of year)How big are the waves at Castlerock today?
The current surf forecast for Castlerock at 5AM is: 0.5m 8s primary swell from a Northwest direction and 0.3m 12s secondary swell from a West-northwest direction (forecast issued at 12:00am May 21). The wind direction is predicted to be offshore.
| Time (BST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (21 May) | 2ft (0.6m) | 8s |
| 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 ForecastModerate rain (total 10mm), heaviest on Thu afternoon. Very mild (max 19°C on Fri afternoon, min 11°C on Wed night). Wind will be generally light. | ||||||||||||||||||||||||
Thursday 21 | Friday 22 | Saturday 23 | ||||||||||||||||||||||
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 | 4 PM | 7 PM | 10 PM | |
Swell Height Map |    |    |    | |||||||||||||||||||||
WNW 12 | NW 8 | NW 8 | NW 8 | NW 8 | WNW 11 | NW 7 | WNW 11 | W 11 | W 11 | W 11 | W 12 | W 11 | W 12 | W 12 | W 12 | WNW 12 | WNW 12 | W 12 | W 12 | WNW 6 | WNW 6 | WNW 6 | WNW 10 | |
28 | 31 | 58 | 41 | 28 | 23 | 12 | 11 | 9 | 9 | 10 | 10 | 10 | 11 | 11 | 11 | 13 | 13 | 3 | 3 | 3 | 3 | 4 | 9 | |
Wind (km/h) | ||||||||||||||||||||||||
cross-off | cross-off | off | off | off | off | off | off | off | off | off | off | off | off | cross-on | cross-off | cross-off | cross-off | off | off | cross-off | cross-off | cross-on | glassy | |
High Tide | 10:02AM1.34m | 10:43PM1.68m | 11:02AM1.19m | 11:57PM1.59m | 12:22PM1.09m | |||||||||||||||||||
Low Tide | 4:31AM0.33m | 4:18PM0.33m | 5:43AM0.45m | 5:20PM0.41m | 7:00AM0.52m | 6:30PM0.46m | ||||||||||||||||||
 | |  |  |  | | |  | |  | | | | | | | |  |  | | | | | | |
 | — | 5:09 | — | — | — | — | — | — | — | 5:07 | — | — | — | — | — | — | — | 5:05 | — | — | — | — | — | — |
 | — | — | — | — | — | — | 9:37 | — | — | — | — | — | — | — | 9:39 | — | — | — | — | — | — | — | 9:42 | — |
— | — | 1 | — | — | 1 | 3 | 1 | — | — | — | — | — | — | 2 | 2 | — | — | — | — | — | — | — | — | |
Temp °C | 12 | 11 | 12 | 15 | 16 | 18 | 15 | 15 | 14 | 13 | 12 | 13 | 18 | 19 | 15 | 13 | 13 | 14 | 12 | 14 | 17 | 19 | 18 | 16 |
9 | 7 | 9 | 13 | 14 | 16 | 13 | 12 | 10 | 9 | 9 | 10 | 15 | 16 | 14 | 13 | 12 | 13 | 10 | 12 | 14 | 16 | 17 | 15 | |
Swell 1 Height (m) Direction Period (s) | WNW 7 | NW 8 | NW 8 | NW 8 | NW 8 | NW 7 | NW 7 | NW 7 | NW 7 | WNW 7 | W 11 | ESE 4 | W 11 | W 12 | W 12 | W 12 | WNW 12 | WNW 12 | W 5 | W 12 | WNW 6 | WNW 6 | WNW 6 | WNW 10 |
 kJ | 18 | 31 | 58 | 41 | 28 | 19 | 12 | 7 | 7 | 4 | 10 | 1 | 10 | 11 | 11 | 11 | 13 | 13 | 1 | 3 | 3 | 3 | 4 | 9 |
Swell 2 Height (m) Direction Period (s) | WNW 12 | WNW 12 | WNW 12 | WNW 11 | WNW 11 | WNW 11 | WNW 11 | WNW 11 | W 11 | W 11 | WNW 6 | W 12 | E 4 | — | — | ESE 4 | E 4 | — | W 10 | W 5 | W 11 | W 11 | W 10 | — |
| kJ | 28 | 28 | 27 | 25 | 12 | 23 | 11 | 11 | 9 | 9 | 4 | 10 | 1 | — | — | 2 | 1 | — | 2 | 1 | 2 | 2 | 2 | — |
Swell 3 Height (m) Direction Period (s) | — | — | — | ESE 3 | — | — | N 9 | N 9 | N 8 | N 8 | N 8 | NW 6 | NW 6 | NW 6 | NW 6 | — | N 6 | N 6 | W 12 | — | — | — | — | — |
| kJ | — | — | — | 1 | — | — | 2 | 2 | 1 | 1 | 1 | 2 | 2 | 2 | 1 | — | 1 | 1 | 3 | — | — | — | — | — |
Wind waves Height (m) Direction Period (s) | — | — | — | SSE 3 | — | — | — | — | SE 3 | SE 3 | SE 3 | — | S 2 | — | — | — | — | — | — | — | — | — | — | — |
| kJ | — | — | — | 1 | — | — | — | — | 2 | 3 | 3 | — | 1 | — | — | — | — | — | — | — | — | — | — | — |
Nearest Offshore or Glassy | ||||||||||||||||||||||||
Distance (km) | 14 | 8 | 0 | 0 | 14 | 40 | 56 | 194 | 83 | 56 | 56 | 56 | 42 | 42 | 41 | 40 | 40 | 42 | 40 | 42 | 42 | 42 | 40 | 40 |
Best forecast wave conditions in Londonderry | ||||||||||||||||||||||||
Best forecast wave conditions in Ireland | ||||||||||||||||||||||||
Header Global | ||||||||||||||||||||||||
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