My sister and I arrived late morning and set up whilst the guys played golf the day. You can see from the first few beach photos the sea wasn't rough, the waves about manageable and a very blue sky. During the day a big swell started to move in and the whole island started to get very excited as it was the first of the season, by the end of the day you can see the spray clouding the sky, the part of the beach my sister and I had our photos taken was getting serious shore break and the waves increased to about 10-15ft. Where everyone is standing on the first photos is about a 6ft shelving drop down to the sea so the wave photos don't look quite as impressive size wise. I wasn't going to risk losing myself and my camera to one of the rogue waves!
The park ended up being shut 4 hours early as the waves started to get out of control and the lifegueards were having to work extremely hard keeping silly people safe. We had been in the sea the day before with waves half this size and came out with bruised heads, one lost wedding ring, back bruises and knee grazes - the sea is not to be messed with kids! I was more than happy just watching, it really was spectactular.
If you go to Oahu, you must visit this beach!