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Castlerock Surf Forecast
/ Londonderry (4 surf breaks) /
Surf Forecasts:
Castlerock surfForecast / Londonderry / Ireland
48hr Weather and Surf, issued 6 pm Sunday 17 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 2AM is: 0.9m 12s primary swell from a West-northwest direction (forecast issued at 06:00pm May 17). The wind direction is predicted to be cross-offshore and the swell rating is 2.
| Time (BST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (18 May) | 3ft (0.9m) | 11s |
| Afternoon (18 May) | 3ft (0.9m) | 11s |
| Evening (18 May) | 2.5ft (0.7m) | 10s |
Table - waves today at Castlerock. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Short Range ForecastModerate rain (total 18mm), heaviest on Sun afternoon. Very mild (max 14°C on Wed morning, min 7°C on Sun night). Winds increasing (calm on Sun night, fresh winds from the SE by Mon night). | ||||||||||||||||||||||||
Sun 17 | Monday 18 | Tuesday 19 | Wed 20 | |||||||||||||||||||||
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 |  |    |    |    | ||||||||||||||||||||
NW 13 | WNW 13 | NW 12 | WNW 12 | WNW 12 | WNW 12 | NW 11 | NW 11 | NW 11 | NW 10 | NW 10 | WNW 10 | NW 10 | WNW 10 | NW 10 | NW 9 | WNW 9 | WNW 9 | WNW 16 | NW 16 | WNW 15 | WNW 15 | WNW 14 | WNW 14 | |
494 | 437 | 353 | 247 | 243 | 231 | 176 | 172 | 169 | 112 | 82 | 67 | 48 | 38 | 23 | 22 | 8 | 8 | 25 | 64 | 135 | 167 | 116 | 104 | |
Wind (km/h) | ||||||||||||||||||||||||
cross-off | cross-on | glassy | glassy | cross-off | cross-off | glassy | cross | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | off | off | off | off | cross-off | cross-off | cross-off | cross-off | cross-off | |
High Tide | 7:17PM1.85m | 7:39AM1.80m | 8:01PM1.88m | 8:25AM1.67m | 8:49PM1.85m | 9:12AM1.51m | ||||||||||||||||||
Low Tide | 1:15PM0.08m | 1:38AM0.07m | 1:55PM0.12m | 2:31AM0.11m | 2:38PM0.18m | 3:28AM0.21m | ||||||||||||||||||
 | |  |  | |  |  | | | |  |  | | | | |  | | | |  | |  | | |
 | — | — | — | — | 5:13 | — | — | — | — | — | — | — | 5:11 | — | — | — | — | — | — | — | 5:11 | — | — | — |
 | — | 9:31 | — | — | — | — | — | — | — | 9:32 | — | — | — | — | — | — | — | 9:35 | — | — | — | — | — | 9:37 |
1 | 2 | 1 | — | — | — | — | — | — | — | — | 2 | 2 | 1 | 2 | 2 | 2 | 2 | 1 | — | — | — | — | — | |
Temp °C | 9 | 9 | 8 | 7 | 7 | 7 | 9 | 11 | 12 | 12 | 9 | 9 | 10 | 10 | 11 | 12 | 13 | 12 | 11 | 10 | 11 | 11 | 12 | 14 |
7 | 7 | 6 | 5 | 4 | 4 | 7 | 8 | 7 | 7 | 3 | 2 | 3 | 5 | 8 | 9 | 10 | 8 | 7 | 6 | 6 | 6 | 7 | 8 | |
Swell 1 Height (m) Direction Period (s) | NW 13 | WNW 13 | NW 12 | WNW 12 | WNW 12 | WNW 12 | NW 11 | NW 11 | NW 11 | NW 10 | NW 10 | WNW 10 | NW 10 | WNW 10 | ESE 5 | ESE 5 | ESE 4 | ESE 4 | WNW 9 | NW 16 | WNW 15 | WNW 15 | WNW 14 | WNW 14 |
 kJ | 494 | 437 | 353 | 247 | 243 | 231 | 176 | 172 | 169 | 112 | 82 | 67 | 48 | 38 | 33 | 13 | 6 | 2 | 8 | 64 | 135 | 167 | 116 | 104 |
Swell 2 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | W 15 | NW 10 | NW 9 | WNW 9 | WNW 9 | WNW 16 | WNW 9 | — | — | — | — |
| kJ | — | — | — | — | — | — | — | — | — | — | — | — | — | 4 | 23 | 22 | 8 | 8 | 25 | 8 | — | — | — | — |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | W 15 | W 14 | NW 13 | NW 13 | E 3 | ESE 3 | — | — | — | — |
| kJ | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 4 | 4 | 7 | 7 | 1 | 1 | — | — | — | — |
Wind waves Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | ESE 2 | SE 3 | ESE 4 | ESE 5 | ESE 6 | — | — | S 3 | — | — | — | — | SW 2 | W 8 | W 8 |
| kJ | — | — | — | — | — | — | — | — | — | 1 | 5 | 18 | 74 | 87 | — | — | 1 | — | — | — | — | 2 | 80 | 80 |
Nearest Offshore or Glassy | ||||||||||||||||||||||||
Distance (km) | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 2 | 2 | 2 | 16 | 292 | 109 | 56 | 16 | 40 | 42 | 40 | 14 | 9 | 9 | 9 | 350 | 354 |
Best forecast wave conditions in Londonderry | ||||||||||||||||||||||||
Best forecast wave conditions in Ireland | ||||||||||||||||||||||||
Header Global | ||||||||||||||||||||||||
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