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Castles Beach surf break

Castles Beach surfForecast / HAW – Oahu / USA

information circle48hr Weather and Surf, issued 1 am Monday 20 Apr 2026 HST
Forecast update in hr  min  s Forecast update imminent
Castles Beach surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.
Today's Castles Beach sea temperature is
24.5° C
(Which is normal for this time of year)

How big are the waves at Castles Beach today?

The current surf forecast for Castles Beach at 4AM is: 0.7m 6s primary swell from a East direction and 0.5m 7s secondary swell from a North-northeast direction (forecast issued at 01:00am April 20). The wind direction is predicted to be onshore.

Time (HST) & DateWave HeightWave Period
Morning (20 Apr)2.5ft (0.8m)7s
Afternoon (20 Apr)2.5ft (0.7m)7s
Evening (20 Apr)2.5ft (0.7m)7s

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


Updates in  hr  min  s Forecast update imminent
Monday
20
Tuesday
21
Wednesday
22
11PM2AM5AM8AM11AM2PM5PM8PM11PM2AM5AM8AM11AM2PM5PM8PM11PM2AM5AM8AM11AM2PM5PM8PM
Rating
(10 max)
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
2
2
2
1
0
1
1
Swell
Height Map
Wave Height (m) & direction (?)
0.8
E
0.8
E
0.9
E
0.8
E
0.7
E
0.7
E
0.7
E
0.7
E
0.7
NNE
0.8
NNE
0.8
NNE
0.9
NNE
0.9
NNE
0.9
NNE
0.9
NNE
0.7
NNE
0.9
NNE
1
NNE
1.1
NNE
1.4
NNE
1.4
NNE
1.3
NNE
1.3
NNE
1.3
NNE
Period(s) (?)666777777778888161514141413131212
Wave
Graph
(?)Metric surfscale
Energy kJ (?)4144626751485151445961889398111223358437494733690587543477
Wind
(km/h)
10
ENE
15
E
10
ESE
10
ESE
10
SE
15
SE
10
ESE
10
ESE
10
ESE
5
S
5
W
5
WNW
5
NNE
5
NE
10
N
10
NNE
10
NE
10
NE
10
NE
10
NE
10
NE
15
NE
15
NE
15
NE
Wind State (?)
onshore
cross-onshore
cross-shore
cross-offshore
offshore
glassy
ononononcross-
on
cross-
on
oncross-
on
cross-
on
glassglassoffglasscross-
on
crosscrosscross-
on
cross-
on
cross-
on
cross-
on
cross-
on
cross-
on
cross-
on
cross-
on
High Tide
/ height (m)
2:49AM
0.50
5:44PM
0.85
2:39AM
0.46
6:53PM
0.81
Low Tide
/ height (m)
11:27PM
0.43
9:45AM
0.02
1:16AM
0.46
10:24AM
0.07
11:10AM
0.14
Monday
20
Tuesday
21
Wednesday
22
Sunrise---6:07-------6:07-------6:05----
Sunset------6:52-------6:52-------6:52-
clear
clear
clear
part cloud
clear
thunderstorm
thunderstorm
part cloud
part cloud
part cloud
clear
clear
part cloud
part cloud
thunderstorm
part cloud
clear
clear
clear
clear
clear
clear
part cloud
clear
Rain (mm)
-----11-------1---------
Temp. °C242423232424242424242423242424242323232323232423
Feels °C (?)262525262625262627272726272726262526262525232524
  • 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

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 Castles Beach 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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