Cancun's Weather Forecast and Climate
Cancun weather is normally fairly consistent throughout the year, with an annual average temperature of around 80°F. In summer, June to August, temperatures can reach up to 90°F while in winter, December to February, temperatures rarely dip below 65°F.
For current weather conditions use a service like CNN - see http://weather.cnn.com/weather/forecast.jsp?locCode=CUN
There are two rainy seasons; the first is from April to July and the second lasts from October to January. It can rain quite a lot during the hottest months but often, because the rain reduces the humidity, this can be a welcome relief and can be a good time to travel if hiking and visiting ruins is your main objective. However, if good diving conditions are what you're after then the rainy season should be avoided as it can decrease visibility.
Even during the rainy season you should manage some sunshine. Mornings are generally clear with rain in the afternoon and sometimes into the night. On some occasions it can rain all day, and sometimes for days. One thing to remember about the rain in Cancun is that, even if rain is forecast it may not necessarily rain in your area. It can be raining in downtown while sunny conditions prevail in the Zona Hotelera.
One of the biggest seasonal concerns tourists have abut Cancun weather reports is hurricanes. The hurricane season starts in June and finishes in October; the worst month is September. The last serious hurricane to hit Cancun was Hurricane Gilbert in September of 2002. Although hurricanes don't hit this area every year, sudden storms can arise with little warning. This is particularly important to remember when going to the beach; if there are dark clouds on the horizon it's best not to swim until they've passed.
Peak season weather information
Peak season in the Yucatan region is from December and continues through to the end of Easter. This period tends to have generally more stable weather conditions and calm waters. In low season, from April to December, prices can drop by 20 percent and even up to 50 percent in some areas. However, new crowds from Europe are beginning to arrive in the summer season and so prices for the low season won't remain cheaper for long.
The steady Cancun weather keeps the temperature of the water consistently warm all year round meaning swimming is a year-round activity.