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Surf Forecasts:
Castlerock surfForecast / Londonderry / Ireland
48hr Weather and Surf, issued 11 pm Tuesday 16 Dec 2025 GMTForecast 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
10.9° C
(Which is slightly warmer than usual)How big are the waves at Castlerock today?
The current surf forecast for Castlerock at 3AM is: 1.2m 13s primary swell from a West-northwest direction (forecast issued at 11:00pm December 16). An open ocean swell of 0.8m 4s is not directed at the surf break. The wind direction is predicted to be offshore.
| Time (GMT) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (17 Dec) | 3.5ft (1.1m) | 13s |
| Afternoon (17 Dec) | 3ft (0.9m) | 13s |
| Evening (17 Dec) | 5ft (1.6m) | 14s |
Table - waves today at Castlerock. (Swell directed towards the surf break)
Updates in hr min s Forecast update imminent
Wednesday 17 | Thursday 18 | Friday 19 | ||||||||||||||||||||||
| 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | 9 PM | 0 AM | 3 AM | 6 AM | 9 AM | 12 PM | 3 PM | 6 PM | |
Rating (10 max) | ||||||||||||||||||||||||
Swell Height Map |  |    |    |    | ||||||||||||||||||||
| Wave Height (m) & direction (?) | ||||||||||||||||||||||||
| Period(s) (?) | 14 | 14 | 13 | 13 | 13 | 13 | 13 | 13 | 14 | 20 | 20 | 20 | 20 | 20 | 19 | 19 | 18 | 18 | 17 | 17 | 16 | 16 | 16 | 16 |
Wave (?)Graph  | ||||||||||||||||||||||||
 kJ (?) | 765 | 607 | 479 | 357 | 414 | 317 | 261 | 346 | 975 | 5632 | 8699 | 8613 | 7897 | 7277 | 7128 | 6866 | 5488 | 4434 | 3850 | 3686 | 3903 | 4574 | 4467 | 3736 |
Wind (km/h) | ||||||||||||||||||||||||
| Wind State (?) onshore cross-onshore cross-shore cross-offshore offshore glassy | off | off | off | off | off | cross- off | cross- off | cross- off | off | cross- off | cross- off | cross- off | cross- off | off | off | cross- off | cross- off | cross- off | cross- off | cross- off | cross- off | cross- off | cross- off | off |
High Tide / height (m) | 4:22AM 1.44 | 4:32PM 1.45 | 4:56AM 1.53 | 5:06PM 1.48 | 5:29AM 1.61 | 5:39PM 1.50 | ||||||||||||||||||
Low Tide / height (m) | 10:18PM 0.41 | 10:39AM 0.44 | 10:53PM 0.36 | 11:20AM 0.38 | 11:27PM 0.31 | 11:58AM 0.35 | ||||||||||||||||||
Wednesday 17 | Thursday 18 | Friday 19 | ||||||||||||||||||||||
| Sunrise | - | - | - | - | 8:48 | - | - | - | - | - | - | - | 8:48 | - | - | - | - | - | - | - | 8:48 | - | - | - |
| Sunset | - | - | - | - | - | - | 3:56 | - | - | - | - | - | - | - | 3:56 | - | - | - | - | - | - | - | 3:57 | - |
 |  |  | |  |  | | | | |  | |  | | | | | | | | |  | | | |
Rain (mm) | - | - | 2 | 2 | 1 | - | - | - | - | - | 1 | - | - | - | 2 | 2 | - | - | 1 | 1 | 1 | 1 | - | - |
| Temp. °C | 5 | 6 | 6 | 8 | 10 | 11 | 10 | 9 | 8 | 8 | 8 | 7 | 6 | 8 | 8 | 7 | 6 | 8 | 8 | 7 | 7 | 8 | 8 | 8 |
| Feels °C (?) | -1 | -1 | -5 | -1 | 4 | 5 | 4 | 4 | 2 | 1 | 1 | 0 | 0 | -1 | 1 | 1 | -3 | -1 | -2 | -3 | -2 | -1 | 1 | 2 |
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
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