Hawaii is on my radar for Christmas week 2020. Would the weather be reliably decent? Also, for a 5-day (first) trip, where would be the best place to start? Of course I am thinking Aulani but is that convenient to other things we would want to do?
ETA: We are not beach people so we'd need some hiking or biking or some other sort of interact with nature activities.
We try to make it back to Oahu over Christmas every year to visit family; usually we'll also try to extend our trip over the New Year. So our typical trip is between 10-14 days over December and January. December is in Hawaii’s rainy season. (So is March for those planning on visiting then.) But that doesn’t mean it’ll be rainy all the time, or even everywhere.
Rain systems tend to come down from the northern, windward side of the island, but the Koolau mountains break up the rain clouds as they make their way southward, so mostly by the time these rain clouds reach the southern side of the island, where you’ll find Waikiki, Honolulu, and Ko Olina (where Aulani is), the rains will have dissipated to scattered showers. Meanwhile, on the other side of the island, the steep vertical cliffsides of the Koolau mountains in the pictures that
@hulagirl shared become filled with plunging waterfalls; and a good rainstorm might result in the Koolaus awash with over a dozen waterfalls.
I’ve posted aerials shot that kind of explain what I mean:
https://www.disboards.com/threads/i-love-credit-cards-so-much.3528202/page-574#post-58615409
ETA: See those rainbows in the distance? Also see the rain. But it was completely dry and sunny at our hotel in Waikiki.
It can be entirely sunny in one spot, and gray and wet if you happen to be under a passing rain cloud. Again, Honolulu and Waikiki will see less rain than the windward side (going up to the North Shore), and Ko Olina is on the dry side of the island so will get even less rain than Honolulu and Waikiki.
The above shots were taken at the end of December 2017 and over New Year 2018-19. In 2017, I think we got some pretty heavy downpour for a day or two while we were at Aulani, but that was about the only real rain we saw during a ~10 days trip. It didn’t faze my kiddo, who enjoyed the lazy river at Aulani just the same since she’d be wet anyway. Last year, in December 2018, I remember we saw about two days with rain in the forecast while we were staying in Waikiki, but it was mostly morning showers that cleared up by noon. We also did have some cool overcast days that gave away to sunshine. Temperatures were between ~78-82.
I will add though, my wife and I got married on Oahu in March, and it rained hard almost the whole week before our wedding day; the weather finally cleared up just in time. But I’ve also been in Hawaii in March when the weather was perfect the entire time.
I generally like visiting in the “rainy” winter seasons because even though rain is kind of unpredictable, the weather is cooler and less muggy.
As for where to stay and how to divide up your time, you might want to do a split stay. Aulani is way on the western side of the island in a private resort community, and its rack rates are expensive if you’re just using it as a base to explore and not going to really be there to enjoy all the amenities. We’ve stayed at Aulani for 5 days, and thought it was too much of a bubble (and I kept thinking we were wasting money every time we stepped off property because we were paying so much to stay there). Waikiki has most of Oahu’s hotels and you’ll easily find something a lot cheaper than Aulani. It’s more central to dining, entertainment, shopping, and commuting to other parts of the island. I’m thinking nature stuff like snorkeling at Hanauma Bay, hiking up Diamond Head or Koko Head craters, Manoa Falls, and Makapuu Lighthouse trail are all much closer from Waikiki. Outdoorsy stuff on the windward side, like Kualoa Ranch and Waimea Valley, and everything else we mentioned yesterday, are probably equally accessible from Waikiki or Ko Olina. We like to unwind at Aulani. Two or three nights there is perfection.