Castlerock surf break

Castlerock surfForecast / Londonderry / Ireland

information circle48hr Weather and Surf, issued 12 pm Wednesday 20 May 2026 BST
Forecast 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 6PM is: 0.4m 13s primary swell from a West-northwest direction and 0.4m 6s secondary swell from a West-northwest direction (forecast issued at 12:00pm May 20). The wind direction is predicted to be cross-offshore.

Time (BST) & DateWave HeightWave Period
Morning (20 May)2ft (0.6m)14s
Afternoon (20 May)1.5ft (0.5m)14s
Evening (20 May)1.5ft (0.4m)12s

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


Updates in  hr  min  s Forecast update imminent

Short Range Forecast

Light rain (total 9mm), mostly falling on Fri night. Very mild (max 19°C on Fri afternoon, min 11°C on Wed morning). Wind will be generally light.

Wed
20
Thursday
21
Friday
22
Sat
23
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
1 AM
4 AM
7 AM
Rating
(10 max)
1
0
0
1
1
1
0
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Swell
Height Map
Height MapHeight MapHeight Map
Height MapHeight MapHeight Map
Height MapHeight MapHeight Map
Height MapHeight MapHeight Map
Wave
Height (m)
Direction
Period (s)
0.6
WNW
14
0.5
WNW
14
0.7
WNW
13
0.4
WNW
13
0.4
WNW
12
0.4
WNW
12
0.5
NW
8
0.5
NW
8
0.6
NW
8
0.5
NW
8
0.3
WNW
11
0.4
NW
7
0.2
W
11
0.2
W
11
0.2
W
11
0.2
W
11
0.2
W
11
0.2
W
11
0.2
W
12
0.2
W
12
0.2
W
12
0.2
W
11
0.2
W
11
0.2
WNW
6
Wave Graph
Metric surfscale
Energy kJ
160
107
181
66
50
48
29
34
41
28
23
12
9
9
9
10
10
9
11
11
11
9
9
3
Wind (km/h)
15
WSW
20
W
20
W
10
WSW
10
S
15
SSE
20
SSE
20
S
20
SSW
20
SW
15
S
15
S
15
SSE
15
SSE
20
SSE
20
SSE
15
S
15
S
20
S
10
N
10
SSE
15
S
15
S
10
S
cross-off
cross
cross
cross-off
off
cross-off
off
off
off
cross-off
off
off
off
off
off
off
off
off
off
on
off
off
off
off
High Tide
9:12AM1.51m
9:42PM1.78m
10:02AM1.34m
10:43PM1.68m
11:02AM1.19m
11:57PM1.59m
Low Tide
3:25PM0.25m
4:31AM0.33m
4:18PM0.33m
5:43AM0.45m
5:20PM0.41m
7:00AM0.52m
rain showers
part cloud
part cloud
clear
part cloud
part cloud
cloud
cloud
cloud
part cloud
cloud
light rain
light rain
cloud
cloud
cloud
cloud
cloud
cloud
light rain
light rain
clear
clear
clear
<span class="translation_missing" title="translation missing: en.weather_tables.sunrise">Sunrise</span>
5:11
5:09
5:07
5:05
<span class="translation_missing" title="translation missing: en.weather_tables.sunset">Sunset</span>
9:37
9:37
9:39
9:42
1
2
1
2
3
Temp °C
11
14
15
15
14
11
11
12
15
18
18
15
15
15
13
13
14
18
19
14
13
13
12
12
8
9
10
12
12
8
8
8
12
14
16
13
13
12
9
10
11
15
15
13
12
11
10
10
Swell 1
Height (m)
Direction
Period (s)
0.6
WNW
14
0.5
WNW
14
0.7
WNW
13
0.4
WNW
13
0.4
WNW
6
0.4
WNW
7
0.5
NW
8
0.5
NW
8
0.6
NW
8
0.5
NW
8
0.4
NW
7
0.4
NW
7
0.3
NW
7
0.3
NW
7
0.2
WNW
7
0.2
WNW
6
0.3
ESE
4
0.2
W
11
0.2
W
12
0.2
W
12
0.2
W
12
0.2
W
11
0.2
W
6
0.2
WNW
6
Energy kJ
160
107
181
66
16
17
29
34
41
28
19
12
7
7
4
4
3
9
11
11
11
9
3
3
Swell 2
Height (m)
Direction
Period (s)
0.4
WNW
6
0.4
WNW
12
0.4
WNW
12
0.3
WNW
12
0.3
WNW
12
0.3
WNW
11
0.2
WNW
11
0.3
WNW
11
0.2
WNW
11
0.2
W
11
0.2
W
11
0.2
W
11
0.2
W
11
0.2
W
11
0.1
NW
6
0.2
ESE
3
0.2
ESE
5
0.2
W
11
0.1
W
10
Energy kJ
13
50
48
27
26
25
12
23
11
9
9
9
10
10
2
1
2
9
2
Swell 3
Height (m)
Direction
Period (s)
0.1
N
9
0.1
N
9
0.1
N
8
0.1
N
8
0.1
N
8
0.1
NW
6
0.1
W
13
0.1
NW
6
0.1
N
6
0.1
N
6
0.1
W
12
Energy kJ
2
2
1
1
1
2
4
2
1
1
3
Wind waves
Height (m)
Direction
Period (s)
0.3
W
2
0.2
SSE
2
0.2
SSW
2
0.3
SE
2
0.4
SE
3
0.4
SE
4
0.4
SE
2
0.2
SSW
2
Energy kJ
1
1
1
1
3
3
2
1
Nearest Offshore or Glassy
Rating
(10 max)
1
4
1
1
1
1
1
1
1
2
2
1
2
1
1
1
1
2
2
2
2
2
2
2
Distance (km)
0
187
71
0
0
0
8
0
0
42
40
41
306
83
67
56
56
42
42
40
40
42
40
40
Best forecast wave conditions in Londonderry
Rating
(10 max)
1
1
1
1
1
1
Best forecast wave conditions in Ireland
Rating
(10 max)
1
4
4
3
3
2
2
2
2
2
2
2
2
3
2
2
1
2
2
2
2
2
2
2
Header Global
Rating
(10 max)
4
4
4
5
5
5
5
5
5
5
5
5
4
5
5
7
7
7
6
5
5
5
5
6
  • 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

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