Surf Forecasts:
How big are the waves at Castlerock today (20 Aug):
- Afternoon surf: Afternoon surf (20 Aug, local time) - 5.5ft (1.7m), 7s period with NNW swell.
- Evening surf: Evening surf (20 Aug, local time) - 5ft (1.6m), 7s period with NNW swell.
The current surf forecast for Castlerock at 9PM is: 1.6m 7s primary swell from a North-northwest direction and 0.3m 9s secondary swell from a West-northwest direction (forecast issued at 06:00pm August 20). The wind direction is predicted to be onshore.
| Time (BST) & Date | Wave Height | Wave Period |
|---|---|---|
| Morning (20 Aug) | - | - |
| Afternoon (20 Aug) | 5.5ft (1.7m) | 7s |
| Evening (20 Aug) | 5ft (1.6m) | 7s |
Table - waves today at Castlerock. (Swell directed towards the surf break)
Short Range ForecastSome drizzle, heaviest during Thu night. Very mild (max 15°C on Sat morning, min 12°C on Thu night). Winds decreasing (fresh winds from the N on Thu afternoon, light winds from the NNW by Sun morning). | |||||||||||||||||||
Thu 20 | Friday 21 | Saturday 22 | |||||||||||||||||
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 | |||||||||||||||||||
Wave Height (m) Direction Period (s) | NNW 7 | NNW 7 | NNW 7 | NNW 7 | NNW 6 | NNW 6 | NNW 6 | NNW 6 | NNW 6 | NNW 6 | NNW 5 | NNW 5 | NNW 5 | NNW 5 | NNW 5 | NNW 5 | NNW 5 | NW 4 | NW 4 |
Wave Graph | |||||||||||||||||||
255 | 212 | 206 | 206 | 165 | 134 | 150 | 130 | 108 | 83 | 74 | 62 | 45 | 33 | 23 | 13 | 12 | 7 | 5 | |
Wind (km/h) | |||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | on | on | on | on | on | on | on | on | on | on | on | on | on | on | on | cross-on | cross-on | cross-on | cross |
High Tide | 11:54PM1.10m | 1:03PM1.11m | 2:29AM1.01m | 3:46PM1.16m | |||||||||||||||
Low Tide | 6:11PM0.68m | 6:42AM0.72m | 8:03PM0.77m | 8:39AM0.74m | |||||||||||||||
— | — | — | — | 6:11 | — | — | — | — | — | — | — | 6:13 | — | — | — | — | — | — | |
— | 8:50 | — | — | — | — | — | — | — | 8:47 | — | — | — | — | — | — | — | 8:45 | — | |
mm | — | — | — | — | — | 1 | — | — | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 13 | 13 | 12 | 13 | 13 | 12 | 13 | 14 | 13 | 13 | 13 | 13 | 13 | 13 | 14 | 15 | 15 | 15 | 13 |
Feels °C | 6 | 7 | 6 | 7 | 7 | 7 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 11 | 11 | 11 | 12 | 11 |
Swell 1 Height (m) Direction Period (s) | WNW 9 | WNW 9 | WNW 9 | WNW 9 | WNW 9 | WNW 8 | WNW 8 | — | WNW 8 | W 8 | W 8 | — | — | W 7 | W 7 | W 7 | W 7 | W 10 | NW 4 |
17 | 17 | 16 | 15 | 7 | 7 | 6 | — | 6 | 1 | 1 | — | — | 1 | 1 | 1 | 1 | 2 | 5 | |
Swell 2 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | W 8 | — | W 10 | W 7 | NW 10 |
— | — | — | — | — | — | — | — | — | — | — | — | — | — | 1 | — | 2 | 1 | 4 | |
Swell 3 Height (m) Direction Period (s) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | W 10 | — | — | — |
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 2 | — | — | — | |
Wind waves Height (m) Direction Period (s) | NNW 7 | NNW 7 | NNW 7 | NNW 7 | NNW 6 | NNW 6 | NNW 6 | NNW 6 | NNW 6 | NNW 6 | NNW 5 | NNW 5 | NNW 5 | NNW 5 | NNW 5 | NNW 5 | NNW 5 | NW 4 | — |
255 | 212 | 206 | 206 | 165 | 134 | 150 | 130 | 108 | 83 | 74 | 62 | 45 | 33 | 23 | 13 | 12 | 7 | — | |
Nearest Offshore or Glassy | |||||||||||||||||||
Distance (km) | 1084 | 339 | 266 | 282 | 284 | 266 | 411 | 411 | 266 | 266 | 266 | 252 | 270 | 282 | 194 | 282 | 282 | 251 | 194 |
Best forecast wave conditions in Londonderry | |||||||||||||||||||
Best forecast wave conditions in Ireland | |||||||||||||||||||
Header Global | |||||||||||||||||||
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