Cozumel has a tropical savanna climate (Aw under the Koppen system) with a distinct wet season from May through October and a dry season from November through April. The island sits in the Caribbean Sea off Mexico’s Yucatan Peninsula at 20 degrees north latitude, which keeps temperatures warm year-round with modest seasonal variation. Average high temperatures range from 28°C (83°F) in December and January to 32°C (90°F) in August. Sea temperatures stay between 26°C (79°F) in winter and 29°C (84°F) in summer, making the water swimmable in every month. The island receives roughly 1,490mm (59 inches) of rain annually, with September and October being the wettest months at over 220mm (9 inches) each. See our best time to visit Cozumel guide.
Cozumel Weather by Month: Monthly Breakdown
January averages a high of 28°C (83°F) and a low of 19°C (66°F). Rainfall is low at about 55mm (2.2 inches) over 7 rainy days. Sea temperature is 26°C (79°F). This is one of the driest and most comfortable months, with humidity around 74%. See our things to do in Cozumel.
February sees similar conditions with highs of 29°C (84°F) and lows of 19°C (67°F). Rainfall drops to roughly 40mm (1.6 inches) across 5 days, making it the driest month. Sea temperature stays at 26°C (79°F). Humidity is around 72%. See our Cozumel events and festivals.
March brings highs of 30°C (86°F) and lows of 21°C (69°F). Rainfall remains low at 35mm (1.4 inches) over 4 rainy days. Sea temperature rises to 27°C (80°F). Sunshine hours increase to 8 per day on average. See our Cozumel neighborhoods guide.
April averages highs of 31°C (88°F) and lows of 22°C (72°F). Rainfall stays moderate at 45mm (1.8 inches) over 5 days. Sea temperature is 27°C (81°F). This marks the transition toward the wet season with slightly higher humidity. See our where to stay in Cozumel.
May reaches highs of 32°C (89°F) and lows of 23°C (74°F). Rainfall jumps to 110mm (4.3 inches) across 8 rainy days as the wet season begins. Sea temperature warms to 28°C (82°F). Afternoon thunderstorms become more common. See our Cozumel travel tips.
June sees highs of 32°C (89°F) and lows of 24°C (76°F). Rainfall increases to 190mm (7.5 inches) over 13 days, with the official start of hurricane season on June 1. Sea temperature reaches 29°C (84°F). Humidity climbs to 80%. See our Cozumel travel guide.
July averages highs of 32°C (90°F) and lows of 24°C (75°F). Rainfall is around 125mm (4.9 inches) across 12 days. Sea temperature is 29°C (84°F). Despite being in the wet season, July often has a mid-summer drying trend called the canicula, with stretches of sunny days between storms.
August brings highs of 32°C (90°F) and lows of 24°C (75°F). Rainfall increases to 155mm (6.1 inches) over 14 days. Sea temperature peaks at 29°C (85°F). This is one of the most humid months at 82%. Hurricane activity typically intensifies.
September sees highs of 32°C (89°F) and lows of 24°C (75°F). Rainfall peaks at 240mm (9.4 inches) across 16 days, making it the wettest month. Sea temperature remains 29°C (84°F). This is the statistical peak of hurricane season for the western Caribbean.
October averages highs of 30°C (87°F) and lows of 23°C (73°F). Rainfall is 220mm (8.7 inches) over 15 days, the second wettest month. Sea temperature is 29°C (84°F). Hurricane risk remains high through late October before tapering off in November.
November brings highs of 29°C (85°F) and lows of 21°C (70°F). Rainfall drops sharply to 100mm (3.9 inches) over 10 days as the dry season begins. Sea temperature is 28°C (82°F). Hurricane season officially ends November 30.
December averages highs of 28°C (83°F) and lows of 20°C (68°F). Rainfall is 70mm (2.8 inches) over 8 days. Sea temperature is 27°C (80°F). Humidity drops to 75% and the weather is reliably dry and pleasant.
Cozumel Weather by Month: Climate Comparison Table
| Month | Avg High | Avg Low | Rainfall (mm) | Rain Days | Sea Temp | Sun (hrs/day) |
|---|---|---|---|---|---|---|
| Jan | 28°C / 83°F | 19°C / 66°F | 55 | 7 | 26°C / 79°F | 6 |
| Feb | 29°C / 84°F | 19°C / 67°F | 40 | 5 | 26°C / 79°F | 7 |
| Mar | 30°C / 86°F | 21°C / 69°F | 35 | 4 | 27°C / 80°F | 8 |
| Apr | 31°C / 88°F | 22°C / 72°F | 45 | 5 | 27°C / 81°F | 8 |
| May | 32°C / 89°F | 23°C / 74°F | 110 | 8 | 28°C / 82°F | 8 |
| Jun | 32°C / 89°F | 24°C / 76°F | 190 | 13 | 29°C / 84°F | 7 |
| Jul | 32°C / 90°F | 24°C / 75°F | 125 | 12 | 29°C / 84°F | 7 |
| Aug | 32°C / 90°F | 24°C / 75°F | 155 | 14 | 29°C / 85°F | 7 |
| Sep | 32°C / 89°F | 24°C / 75°F | 240 | 16 | 29°C / 84°F | 6 |
| Oct | 30°C / 87°F | 23°C / 73°F | 220 | 15 | 29°C / 84°F | 6 |
| Nov | 29°C / 85°F | 21°C / 70°F | 100 | 10 | 28°C / 82°F | 6 |
| Dec | 28°C / 83°F | 20°C / 68°F | 70 | 8 | 27°C / 80°F | 6 |
Cozumel Weather by Month: Hurricane Season
The Atlantic hurricane season runs from June 1 through November 30, with the statistical peak in the western Caribbean occurring between mid-August and late October. Cozumel has been directly hit by major hurricanes including Hurricane Wilma (Category 5, October 2005), which devastated the island and closed it to tourism for months. More recently, Hurricane Delta (Category 2, October 2020) caused moderate damage. The island has a well-developed warning and evacuation system. Hotels and dive shops monitor weather closely and will cancel water activities with 24 to 48 hours’ notice when a storm approaches. Travel insurance that covers hurricane-related cancellations is worth purchasing for trips between August and October.
Cozumel Weather by Month: Diving and Snorkeling Conditions
Water visibility in Cozumel averages 30 metres (100 feet) year-round, with the clearest conditions typically occurring from December through May when there is less runoff and plankton. Water temperatures range from 26°C (79°F) in winter to 29°C (84°F) in summer. Most divers are comfortable in a 3mm wetsuit in winter and a rash guard or shorty in summer. Currents in the Cozumel channel are strongest from November through March, which can make drift diving more challenging but also brings nutrient-rich water that attracts larger pelagic species including eagle rays and sharks. The famous bull shark season runs from November through February off the southern reefs.
