Alaska weather is quite fickle. There is no way to predict whether it will be too cold to swim in the outdoor pools. It can be in the 70's one day and in the 50's the next day - or sometimes even in the same day. However the Calypso pool has a magrodome roof so they can close it and make it an indoor pool. I believe this is normally an adults area but in Alaska I've seen cruise ships allow children to use the adult pools if it is too cool outside.