The weather can be 70s during the day in Januray, or even 80s....we had a nice 10 day run in the 80s last January. However, we can also get down in the 50s for a day or two and can dip into the high 30s at night. So you really need to pack for anything and everything. And even though the pools are heated, it's not great swimming weather in general.
The weather pattern here in the winter is similar to what we used to experience when we lived up north. Similar weather for anywhere from 3 to 7 days and then a cold front moves through. In the summer...with the effect of the sea breezes colliding it's a totally different ballgame. We get hot, humid and thunderstorms.