The best time to visit Cancún is the dry season from December to April, when it is warm (around 23–30°C), rain is rare, the Caribbean is at its clearest and — importantly — sargassum seaweed is usually at its lowest. January to March are the prime months. The summer and early autumn (June to October) are hotter and more humid, and fall within the Atlantic hurricane season, which runs early June to early November and peaks August to October; direct hits on the Yucatán are uncommon but passing storms bring rain and wind. This warmer half of the year is also when sargassum is heaviest, and 2026 has been forecast as a record or near-record sargassum year with unusually early arrivals, so if clean, clear beaches are your priority, aim for late autumn through early spring and check daily beach conditions.
Sargassum, a brown seaweed, drifts onto Cancún's Caribbean beaches mainly from spring through summer, and 2026 is forecast to be an especially heavy year. It is not dangerous but can pile up, smell as it rots and cloud the water. Check daily sargassum trackers before a beach day, favour the more protected north-facing beaches and Isla Mujeres (Playa Norte), and consider resort pools when it is bad.
Cancún's hurricane season runs from early June to early November, peaking between August and October. Direct strikes are rare, but a passing storm can bring heavy rain, wind and travel disruption. If you travel in this window, consider travel insurance, keep an eye on the forecast, and follow your hotel's and the authorities' guidance during any storm warning.
The tourist areas of Cancún are generally safe and heavily policed, and most visits are trouble-free, but use normal city sense: watch your belongings and drinks in busy nightlife spots, avoid buying drugs (a common trigger for trouble), keep valuables in the hotel safe, and use Uber or a hotel-called taxi late at night rather than walking alone in unlit areas.