It just does not get any better than the weather on Cozumel. With an incredible low of only 66 degrees Fahrenheit to a modest high of 93, even the worst of what we would call "winter" is still quite wonderful. Most of the time, the temperature hovers around the mid to high eighties and, incredibly, so do the surrounding ocean waters of the island. Lying in the midday, summertime sun, in temperatures around 90 degrees and then "cooling off" in the ocean waters of about 80 to 85 degrees is unimaginable to most travelers.
Typically, the ocean water is a lot cooler than the land temperature – but not on Cozumel. Some tourists have described the ocean around the island as a huge bath. With a gentle, shallow coastline extending far out into the ocean, the ocean temperatures off the beaches tend to complement the land temperatures, allowing tourists to spend as much time in the water as on the sand. The water temperatures tend to be at their warmest during the summer months but even during the worst of winters, they only cool down to the mid to high 70's.
The temperatures in Cozumel are at their coolest from October to April just like most of the mainland. Due to the location of the island, the temperature never gets too low or too high. There have been storms, known as Nortes, that can bring the evening temperatures in the winter down to the high 50's but that is as low as it ever gets. Summertime highs occasionally approach 100 degrees Fahrenheit, but this is rare. The humidity, however, can make things quite wet. It tends to rain on the island during the month of June but the winter months are quite dry.
Nortes, with pelting rain and high winds, sometimes cause problems during the winter months, but the storms pass over the island quickly and do not do much damage. Most people do not even get up from their hammocks, but view the winds and rain as a gentle, cooling wash from Mother Nature. There's not much to complain about in Cozumel and overall the weather is almost always added attraction to the island rather than a force to be reckoned with. There's almost no bad time to come to Cozumel and the only thing to be taken into account when booking your trip may be the increased humidity during the summer months.