I have taken this cruise in Dec, Jan, Feb, Mar and April and have never encountered rain or any cool weather. The first night at sea is chilly, 1st full day at sea is nice, maybe a cloud or two but when the sun shines thru it is awesome. 2nd day at sea warm and beautiful. We hang out at the pool most of the day. In port it is very warm and you would only need a sweater in the early morning around 7-8am. Last day at sea we go against the current and it gets pretty windy but the last three cruises the last was very warm. When you board the ship in LA you will be very surprised how warm it is in LA. We have seen 90 degree weather on December 26th. These months are the best months to go as the raining season is June 1 - Nov 1 and it is very very hot and humid in Mexico, but the rain will feel great!