We were there Sept. 30-Oct. 9 last year. The weekend was very crowded at Aulani. We used those days to go explore more of the island. There was both a hurricane to the south and a tropical storm to the north that created very high waves quite early in the season. There was no swimming on the North Shore beaches. That was a bummer, but on the flip side, we saw some impressive surfing. The effect of those storms combined with the beginning of winter brought more rain to the rainy side of the island. It was raining on & off as we explored parts of North Shore. Our Kualoa Ranch tours were not as pleasant in the rain, as the views were shrouded in clouds and mist. However, I guess rain should be expected in a rainforest, right? The most disappointing was that our helicopter ride couldn't go all the way around the island due to the weather. It was beautiful, perfect, and sunny in Ko 'Olina, but we had to turn around just past Hanauma Bay because the winds were too rough and we couldn't see anything anyway. As a consolation, we got some extra time on the western coast of the island.
Would I go again during this time? Absolutely!! Enjoy your trip!