Cozumel weather is one of the reasons why Mexico's largest island is so popular. But not every month is the best time to go because of rain in the fall and cool temperatures in the winter.
In addition to great weather most of the year, Cozumel's popularity is due in part to beautiful beaches and being a major stop on most western Caribbean cruises, which take advantage of the destination's well-known emphasis on scuba diving and snorkeling.
Cozumel climate has an average monthly high temperature of nearly 88 degrees Fahrenheit – one of the warmest in the Caribbean region – and an average monthly low temperature of just under 72 degrees – one of the coolest in the region, according to the World Meteorological Organization.
Average high temperatures peak at about 90 degrees from April through September, which is a lengthy period of hot temperatures by Caribbean standards. The average highs decline to the low 80s for the winter months of December through February.
Average low temperatures hover around the mid-70s from May through October. But they are in the high 60s for December through March. Visitors will find cool nights and cool swimming in the ocean.
Cozumel receives an average of about 4.9 inches of rainfall per month. It peaks at 9.5 inches each in September and October during the height of the Caribbean hurricane season, while it bottoms at less than 2 inches in March and April.
The average number of rain days on the island hits 15 in September and October and declines to 4 inches or less in March and April.
Weather by Season
Cozumel weather in December through February has an average high in the low 80s, an average low in the high 60s and eight days of rain.
Spring has average highs in the upper 80s, average lows in the low 70s and five days of rain.
Summer has highs above 90, lows in the mid 70s and nine days of rain.
Fall has highs in the upper 80s, lows in the low 70s and 14 days of rain.
Best and Worst Months
The most popular months to visit are February and March, with another surge of visitors in June through August, according to the Caribbean Tourism Organization. Cruise visitors will find that moderate warmth in February and March is more comfortable than the 90-degree weather the island sees starting in April.
The least popular months are September, October and November because of heavy rainfall, and again in January because of cool weather.