We went at the end of January this year, after only summer trips, and I have to say that packing was the most stressful part of the trip. From what I've heard, it's similar to December. I packed everything under the sun because everyone said the weather was so unpredictable. I had t-shirts, long-sleeved shirts, fleece, shorts, pants, sun hats, winter hats, mitts , shoes, flip flops, ponchos,bathing suits and some winter coats. Now, multiply that by the 2 adults and 6 kids in our family and you'll get my frustration. It was ridiculous how much stuff we had. As it turned out, it was an unusually warm week with temps in the high 80's all week so 3/4 of the stuff we didn't need. My cousin went 2x in Dec. and on one trip had to break out the winter coats, hats and mitts. Unfortunately, I think at that time of year there's no telling what the weather will be like exactly. At least summer you know...hot,hot and more hot.