Castlerock Surf Break

Lat Long: 55.17° N 6.78° W

Castlerock 48 hour detailed Surf Forecast

Issued: 12 am 20 Aug 2026 (local time)

Forecast update in  hr  min

Today's Castlerock sea temperature is
16.1° C
1.5° 

Castlerock surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.


How big are the waves at Castlerock today (20 Aug):

  • Morning surf: Morning surf (20 Aug, local time) - 4ft (1.2m), 8s period with NNW swell.
  • 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) - 5.5ft (1.7m), 7s period with NNW swell.

The current surf forecast for Castlerock at 9AM is: 1.2m 8s primary swell from a North-northwest direction and 0.4m 10s secondary swell from a West-northwest direction, 0.2m 3s secondary swell from a East-northeast direction (forecast issued at 12:00am August 20). The wind direction is predicted to be onshore.

Time (BST) & DateWave HeightWave Period
Morning (20 Aug)4ft (1.2m)8s
Afternoon (20 Aug)5.5ft (1.7m)7s
Evening (20 Aug)5.5ft (1.7m)7s

Table - waves today at Castlerock. (Swell directed towards the surf break)


Short Range Forecast

Light rain (total 9mm), mostly falling on Wed night. Very mild (max 15°C on Sat morning, min 12°C on Wed night). Winds increasing (light winds from the N on Wed night, fresh winds from the N by Thu afternoon).

Thursday
20
Friday
21
Saturday
22
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
Rating
(10 max)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Swell
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Wave
Height (m)
Direction
Period (s)
0.7
NW
10
0.7
WNW
10
1
NNW
8
1.2
NNW
8
1.5
NNW
7
1.8
NNW
7
1.6
NNW
7
1.7
NNW
7
1.6
NNW
7
1.5
N
6
1.3
NNW
6
1.3
NNW
6
1.2
NNW
6
1
NNW
6
0.9
NNW
5
0.9
NNW
5
0.9
NNW
5
0.8
NNW
5
0.6
NNW
5
0.5
NNW
5
0.6
NNW
4
0.5
NW
5
0.6
NNW
5
0.6
NNW
5
Wave Graph
Metric surfscale
Energy kJ
96
85
130
183
222
285
239
268
239
194
134
126
101
69
51
48
46
32
18
13
13
10
14
19
Wind (km/h)
10
N
20
NNE
15
NNE
20
N
30
N
35
N
30
NNW
30
NNW
30
NNW
30
NNW
25
N
25
N
25
N
25
NNW
25
NNW
25
NNW
20
NNW
20
NW
15
WNW
20
NW
15
NW
20
NW
15
NW
15
W
Wind State
on
on
on
on
on
on
on
on
on
on
on
on
on
on
on
on
on
cross-on
cross-on
cross-on
cross-on
cross-on
cross-on
cross
High Tide
11:03PM1.28m
11:24AM1.21m
11:54PM1.10m
1:03PM1.11m
2:29AM1.01m
3:46PM1.16m
Low Tide
5:35AM0.63m
6:11PM0.68m
6:42AM0.72m
8:03PM0.77m
8:39AM0.74m
light rain
rain showers
light rain
rain showers
clear
part cloud
clear
part cloud
part cloud
part cloud
rain showers
light rain
clear
clear
part cloud
cloud
part cloud
clear
clear
clear
clear
clear
clear
cloud
<span class="translation_missing" title="translation missing: en.weather_tables.sunrise">Sunrise</span>
6:09
6:11
6:13
<span class="translation_missing" title="translation missing: en.weather_tables.sunset">Sunset</span>
8:50
8:47
8:45
 mm
1
1
2
2
1
1
Temp °C
13
13
12
13
14
14
13
12
13
12
12
13
13
13
13
13
13
13
12
14
15
15
14
13
Feels °C
11
10
9
9
8
7
6
5
6
6
6
8
8
8
8
8
9
9
9
10
12
11
11
11
  • Map Icons:
  • Break
  • Live Wave Height (m)
  • Live Wind Speed (km/h)
  • Surf Rating (10 Max)
  • Ocean Swells (m)
  • Wind Speed (km/h)
Map placeholder
How to use the Wavefinder 

FREE! Surf-Forecast.com widget for your website

The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Castlerock surf forecast. Simply grab the html code snippet that we provide and paste it into your own site. You can choose your preferred language and metric/imperial units for the surf forecast feed to suit users of your site. Click here to get the code.


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