Hi, not sure what your frame of reference is. For us we have gone in March and for the last 3 yrs late Jan into Feb. Have not felt a big difference in ocean temp, except pools seem a little cooler earlier in the yr, but not really an issue.
Orient can be windy but found no difference between the times we have been. Though I’ve read here that winds over Xmas and into early Jan can stronger
We travel wearing a light pile jacket for the plane, our thinking is it could double as an evening cover when on island, but we have never had to use them.
Hope that helps
J&B